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Nobrega DB, French JE, Kelton DF. A scoping review of the testing of bulk tank milk to detect nonbacterial pathogens or herd exposure to nonbacterial pathogens in dairy cattle. J Dairy Sci 2023; 106:5636-5658. [PMID: 37291033 DOI: 10.3168/jds.2022-22586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Accepted: 02/06/2023] [Indexed: 06/10/2023]
Abstract
In this scoping review, we characterized the literature reporting on the testing of bulk milk samples to detect microorganisms other than bacteria that can cause diseases in dairy cattle, including viruses, helminths, algae, and protozoa. A search strategy was completed by screening databases, conference proceedings, animal health agency websites, disease surveillance program websites, and handbooks of cattle-related diagnostic tests for potentially relevant articles. Two reviewers independently screened articles in English, Portuguese, or Spanish; original studies reporting on the testing of farm-level, unprocessed bulk milk samples for presence of pathogens or specific antibodies against agents other than bacteria that can cause diseases in cows were retained. From all studies, we used spreadsheets to extract relevant information, including pathogen screened, test used, and country of origin of bulk milk samples. Additionally, for studies reporting sufficient data to estimate test characteristics, we extracted detailed information about herd eligibility, testing protocol, and herd-level infection definition. A total of 8,829 records were identified, from which 1,592 were retained and assessed for eligibility, and 306 were included. Bovine viral diarrhea virus, Fasciola hepatica, Ostertagia ostertagi, and bovine herpesvirus 1 were the most frequently screened agents, reported from 107, 45, 45, and 33 studies, respectively. Sensitivity of bulk milk ELISA to detect herds with animals infected by bovine herpesvirus 1 ranged from 2 to 100%, and was affected mostly by antigen selection, cut-off adopted, herd vaccination status, and seroprevalence of lactating cows. Bulk milk ELISA had very high specificity to detect herds free of bovine leukemia virus, and varying sensitivity to detect herds with infected animals, which depended on the within-herd seroprevalence of lactating cattle. As for bovine viral diarrhea virus, in general, the sensitivity of bulk milk ELISA was moderate to high (>80%) when infection status was defined based on presence of persistently infected cattle or a high proportion of seropositive lactating cattle. Nevertheless, bulk milk ELISA was not able to distinguish infected and noninfected herds based on presence of seropositive unvaccinated weanlings. The PCR or quantitative PCR protocols employed had very low sensitivities (<40%) and very high specificities (>95%) to classify bovine viral diarrhea virus infection status of dairy herds. Sensitivity and specificity of bulk milk ELISA to classify herds with regards to presence of F. hepatica- or O. ostertagi-parasitized cattle were generally high and driven mostly by the definition of herd infection status. Conversely, bulk milk ELISA demonstrated varying characteristics to detect herds with or without Dictyocaulus viviparus-parasitized cattle, depending primarily on the antigen selected and presence of cattle with clinical signs of lungworm infection.
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Affiliation(s)
- Diego B Nobrega
- Department of Population Medicine, Ontario Veterinary College, University of Guelph, Guelph, ON, N1G 2W1, Canada.
| | - Julie E French
- Department of Population Medicine, Ontario Veterinary College, University of Guelph, Guelph, ON, N1G 2W1, Canada
| | - David F Kelton
- Department of Population Medicine, Ontario Veterinary College, University of Guelph, Guelph, ON, N1G 2W1, Canada
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Howell A, Caminade C, Brülisauer F, Mitchell S, Williams D. Is the Ollerenshaw fasciolosis forecasting model fit for the 21st century? Vet Rec 2023; 193:e2781. [PMID: 36871278 DOI: 10.1002/vetr.2781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 01/19/2023] [Accepted: 02/07/2023] [Indexed: 03/06/2023]
Abstract
BACKGROUND The Ollerenshaw forecasting model is based on rainfall and evapotranspiration and has been in use to predict losses from fasciolosis since 1959. We evaluated the performance of the model against observed data. METHODS Weather data were used to calculate, map and plot fasciolosis risk values for each year from 1950 to 2019. We then compared the model's predictions with recorded acute fasciolosis losses in sheep from 2010 to 2019 and calculated the sensitivity and specificity of the model. RESULTS The forecast risk has varied over time but has not markedly increased over the past 70 years. The model correctly forecasted the highest and lowest incidence years at both the regional and national (Great Britain) levels. However, the sensitivity of the model for predicting fasciolosis losses was poor. Modification to include the full May and October rainfall and evapotranspiration values made only a small improvement. LIMITATIONS Reported acute fasciolosis losses are subject to bias and error due to unreported cases and variations in region size and livestock numbers. CONCLUSION The Ollerenshaw forecasting model, in either its original or modified forms, is insufficiently sensitive to be relied upon as a standalone early warning system for farmers.
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Affiliation(s)
- Alison Howell
- Department of Infection Biology and Microbiomes, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Neston, UK
| | - Cyril Caminade
- Department of Infection Biology and Microbiomes, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Neston, UK
- Department of Earth System Physics, International Centre for Theoretical Physics, Trieste, Italy
| | | | - Sian Mitchell
- Carmarthen Veterinary Investigation Centre, APHA, Carmarthen, UK
| | - Diana Williams
- Department of Infection Biology and Microbiomes, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Neston, UK
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3
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Beesley NJ, Cwiklinski K, Allen K, Hoyle RC, Spithill TW, La Course EJ, Williams DJL, Paterson S, Hodgkinson JE. A major locus confers triclabendazole resistance in Fasciola hepatica and shows dominant inheritance. PLoS Pathog 2023; 19:e1011081. [PMID: 36701396 PMCID: PMC9904461 DOI: 10.1371/journal.ppat.1011081] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2022] [Revised: 02/07/2023] [Accepted: 12/22/2022] [Indexed: 01/27/2023] Open
Abstract
Fasciola hepatica infection is responsible for substantial economic losses in livestock worldwide and poses a threat to human health in endemic areas. The mainstay of control in livestock and the only drug licenced for use in humans is triclabendazole (TCBZ). TCBZ resistance has been reported on every continent and threatens effective control of fasciolosis in many parts of the world. To date, understanding the genetic mechanisms underlying TCBZ resistance has been limited to studies of candidate genes, based on assumptions of their role in drug action. Taking an alternative approach, we combined a genetic cross with whole-genome sequencing to localise a ~3.2Mbp locus within the 1.2Gbp F. hepatica genome that confers TCBZ resistance. We validated this locus independently using bulk segregant analysis of F. hepatica populations and showed that it is the target of drug selection in the field. We genotyped individual parasites and tracked segregation and reassortment of SNPs to show that TCBZ resistance exhibits Mendelian inheritance and is conferred by a dominant allele. We defined gene content within this locus to pinpoint genes involved in membrane transport, (e.g. ATP-binding cassette family B, ABCB1), transmembrane signalling and signal transduction (e.g. GTP-Ras-adenylyl cyclase and EGF-like protein), DNA/RNA binding and transcriptional regulation (e.g. SANT/Myb-like DNA-binding domain protein) and drug storage and sequestration (e.g. fatty acid binding protein, FABP) as prime candidates for conferring TCBZ resistance. This study constitutes the first experimental cross and genome-wide approach for any heritable trait in F. hepatica and is key to understanding the evolution of drug resistance in Fasciola spp. to inform deployment of efficacious anthelmintic treatments in the field.
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Affiliation(s)
- Nicola J. Beesley
- Veterinary Parasitology, Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, United Kingdom
- * E-mail: (NJB); (JEH)
| | - Krystyna Cwiklinski
- Veterinary Parasitology, Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Katherine Allen
- Veterinary Parasitology, Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Rebecca C. Hoyle
- Veterinary Parasitology, Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Terry W. Spithill
- Department of Animal, Plant and Soil Sciences and Centre for AgriBioscience, La Trobe University, Bundoora, Australia
| | | | - Diana J. L. Williams
- Veterinary Parasitology, Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Steve Paterson
- Centre for Genomic Research, Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Jane E. Hodgkinson
- Veterinary Parasitology, Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, United Kingdom
- * E-mail: (NJB); (JEH)
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4
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Alba A, Grech-Angelini S, Vázquez A, Alda P, Blin Q, Lemmonier L, Chauvin A, Chartier C, Douchet P, Hurtrez-Boussès S, Rey O, Foata J, Boissier J, Quilichini Y. Fasciolosis in the Mediterranean island of Corsica (France): Insights from epidemiological and malacological investigations. Food Waterborne Parasitol 2023; 30:e00188. [PMID: 36718346 PMCID: PMC9883184 DOI: 10.1016/j.fawpar.2023.e00188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Revised: 01/11/2023] [Accepted: 01/16/2023] [Indexed: 01/21/2023] Open
Abstract
Fasciolosis is a re-emergent parasitic disease of worldwide significance with a major global impact on livestock health and production. In the French Mediterranean island of Corsica, fasciolosis has been recognized for a long time but little is known about its dynamic as the main investigations are outdated. Three compartments - definitive domestic hosts, intermediate hosts and environment - involved in fasciolosis transmission were studied by applying an integrative and extensive approach: (1) farm and abattoir surveys, (2) snail sampling, identification and infection prospection, and (3) snail habitat analysis; and (4) a questionnaire-based survey to inquire about husbandry practices and environmental risks. Our results indicate a significant circulation of the liver flukes in Corsican livestock, with 90% (252/279) of the sampled farms testing positive for anti-F. hepatica antibodies. At the abattoir, 46% (67/149) of cattle were positive for F. hepatica antibodies and eggs were present in the bile of 19% (26/139) bovines. In addition, high prevalence of Dicrocoelium dendriticum (69%) was observed in slaughtered cattle. Malacological surveys registered the occurrence of several lymnaeid species in a variety of habitats throughout the island. In particular, we report for the first time the presence of the invasive lymnaeid snail Pseudosuccinea columella in Corsica, a potential intermediate host for F. hepatica. We also found that the presence of Galba truncatula and, to a lesser extent, that of Peregriana peregra, is associated with altitude. Fasciola hepatica DNA was detected in the latter species occurring at two different sites. Finally, a questionnaire-based study revealed risky management practices among Corsican farmers, low perception of transmission and a suboptimal use of flukicide treatments as main control strategy. Our results show that animal fasciolosis in Corsica is characterised by a significant circulation and a favourable epidemiological scenario for transmission to occur.
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Affiliation(s)
- A. Alba
- Laboratoire de Sciences Pour l'Environnement, UMR 6134, CNRS, Université de Corse Pasquale Paoli, Corte, Corse, France,Centro de Investigaciones, Diagnóstico y Referencia, Instituto de Medicina Tropical “Pedro Kourí”, La Habana, Cuba,Corresponding author at: Laboratoire de Sciences Pour l'Environnement, UMR 6134, CNRS, Université de Corse Pasquale Paoli, Corte, Corse, France.
| | | | - A.A. Vázquez
- Centro de Investigaciones, Diagnóstico y Referencia, Instituto de Medicina Tropical “Pedro Kourí”, La Habana, Cuba,MIVEGEC, Université de Montpellier, CNRS, IRD, Montpellier, France
| | - P. Alda
- MIVEGEC, Université de Montpellier, CNRS, IRD, Montpellier, France,Centro de Recursos Naturales Renovables de la Zona Semiárida (CERZOS–CCT–CONICET Bahía Blanca), Bahía Blanca, Argentina
| | - Q. Blin
- Laboratoire de Sciences Pour l'Environnement, UMR 6134, CNRS, Université de Corse Pasquale Paoli, Corte, Corse, France
| | - L. Lemmonier
- Laboratoire de Sciences Pour l'Environnement, UMR 6134, CNRS, Université de Corse Pasquale Paoli, Corte, Corse, France
| | | | | | - P. Douchet
- IHPE, Univ. Montpellier, CNRS, Ifremer, Univ. Perpignan Via Domitia, Perpignan, France
| | - S. Hurtrez-Boussès
- MIVEGEC, Université de Montpellier, CNRS, IRD, Montpellier, France,CREES, Montpellier, France,Département de Biologie-Écologie, Faculté des Sciences, Université de Montpellier, Montpellier, France
| | - O. Rey
- IHPE, Univ. Montpellier, CNRS, Ifremer, Univ. Perpignan Via Domitia, Perpignan, France
| | - J. Foata
- Laboratoire de Sciences Pour l'Environnement, UMR 6134, CNRS, Université de Corse Pasquale Paoli, Corte, Corse, France
| | - J. Boissier
- IHPE, Univ. Montpellier, CNRS, Ifremer, Univ. Perpignan Via Domitia, Perpignan, France
| | - Y. Quilichini
- Laboratoire de Sciences Pour l'Environnement, UMR 6134, CNRS, Université de Corse Pasquale Paoli, Corte, Corse, France
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5
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Kelley JM, Stevenson MA, Rathinasamy V, Rawlin G, Beddoe T, Spithill TW. Analysis of daily variation in the release of faecal eggs and coproantigen of Fasciola hepatica in naturally infected dairy cattle and the impact on diagnostic test sensitivity. Vet Parasitol 2021; 298:109504. [PMID: 34271316 DOI: 10.1016/j.vetpar.2021.109504] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Revised: 06/15/2021] [Accepted: 06/23/2021] [Indexed: 11/16/2022]
Abstract
The liver fluke, Fasciola hepatica (F. hepatica) is a widespread parasite infection in dairy cattle in Victoria, South-eastern Australia. Robust diagnosis of fluke infection is needed in dairy cattle to identify sub-clinical infections which often go unnoticed, causing significant production losses. We tested the coproantigen ELISA (cELISA) and the FlukeFinder faecal egg count kit® on naturally infected cows in a fluke endemic region of Victoria. The aim of the study was to investigate the variation in the release of coproantigens and eggs into faeces over a 5-day period, at the morning (AM) and afternoon (PM) milkings, and to assess the impact of the timing of faecal sample collection on diagnostic test sensitivity. Ten cows were enrolled into the study based on positive F. hepatica faecal egg counts (LFEC) and faecal samples from the ten cows were collected twice daily, at the 7-9 AM and 4-6 PM milking, for five consecutive days. At the conclusion of the sampling period, the cows were euthanized and F. hepatica burden determined at necropsy. A moderate negative correlation between cow age and cELISA optical density (OD) was observed using data from all samples (R -0.63; 95 % CI -0.68 to -0.57). Over the 5-day sampling period, we observed within-animal variation between days for both the cELISA OD (2.6-8.9 fold) and LFEC (5-16 fold), with more variation in values observed in the PM samples for both tests. The correlation with total fluke burden was higher in the AM sampling using both the cELISA and LFEC (R 0.64 and 0.78, respectively). The sensitivity was 100 % for the cELISA using various cut offs from the literature (0.014 OD, 0.030 OD, and 1.3 % or 1.6 % of the positive control). The sensitivity of the FlukeFinder kit® (based on 588 faecal samples and not accounting for lack of independence in the data) was 88 % (95 % CI 85 %-90 %). Seventy one false negatives were recorded from the 588 LFEC tests all of which were observed in the cows with fluke burdens <14 flukes; 42 of the 71 false negative LFECs occurred in one individual cow which had the lowest burden of nine flukes. In dairy cows, the cut-off for production losses due to fasciolosis is estimated at> 10 fluke. Both the cELISA and the LFEC identified all cows that had burdens equal to or greater than this cut-off. Five of the ten cows also exhibited relatively high paramphistome egg counts.
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Affiliation(s)
- Jane M Kelley
- Department of Animal, Plant and Soil Sciences, Centre for AgriBioscience, La Trobe University, Bundoora, Victoria, 3083, Australia
| | - Mark A Stevenson
- Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, Victoria, 3010, Australia
| | - Vignesh Rathinasamy
- Department of Animal, Plant and Soil Sciences, Centre for AgriBioscience, La Trobe University, Bundoora, Victoria, 3083, Australia
| | - Grant Rawlin
- Department of Jobs, Precincts and Regions, Centre for AgriBioscience, La Trobe University, Bundoora, Victoria, 3083, Australia
| | - Travis Beddoe
- Department of Animal, Plant and Soil Sciences, Centre for AgriBioscience, La Trobe University, Bundoora, Victoria, 3083, Australia
| | - Terry W Spithill
- Department of Animal, Plant and Soil Sciences, Centre for AgriBioscience, La Trobe University, Bundoora, Victoria, 3083, Australia.
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6
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Alba A, Vazquez AA, Hurtrez-Boussès S. Towards the comprehension of fasciolosis (re-)emergence: an integrative overview. Parasitology 2021; 148:385-407. [PMID: 33261674 PMCID: PMC11010171 DOI: 10.1017/s0031182020002255] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 11/24/2020] [Accepted: 11/24/2020] [Indexed: 02/06/2023]
Abstract
The increasing distribution and prevalence of fasciolosis in both human and livestock are concerning. Here, we examine the various types of factors influencing fasciolosis transmission and burden and the interrelations that may exist between them. We present the arsenal of molecules, 'adjusting' capabilities and parasitic strategies of Fasciola to infect. Such features define the high adaptability of Fasciola species for parasitism that facilitate their transmission. We discuss current environmental perturbations (increase of livestock and land use, climate change, introduction of alien species and biodiversity loss) in relation to fasciolosis dynamics. As Fasciola infection is directly and ultimately linked to livestock management, living conditions and cultural habits, which are also changing under the pressure of globalization and climate change, the social component of transmission is also discussed. Lastly, we examine the implication of increasing scientific and political awareness in highlighting the current circulation of fasciolosis and boosting epidemiological surveys and novel diagnostic techniques. From a joint perspective, it becomes clear that factors weight differently at each place and moment, depending on the biological, environmental, social and political interrelating contexts. Therefore, the analyses of a disease as complex as fasciolosis should be as integrative as possible to dissect the realities featuring each epidemiological scenario. Such a comprehensive appraisal is presented in this review and constitutes its main asset to serve as a fresh integrative understanding of fasciolosis.
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Affiliation(s)
- Annia Alba
- Centro de Investigaciones, Diagnóstico y Referencia, Instituto de Medicina Tropical ‘Pedro Kourí’, Havana, Cuba
| | - Antonio A. Vazquez
- Centro de Investigaciones, Diagnóstico y Referencia, Instituto de Medicina Tropical ‘Pedro Kourí’, Havana, Cuba
- MIVEGEC, IRD, CNRS, Université de Montpellier, Montpellier, France
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7
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Beltrame L, Rose Vineer H, Walker JG, Morgan ER, Vickerman P, Wagener T. Discovering environmental management opportunities for infectious disease control. Sci Rep 2021; 11:6442. [PMID: 33742016 PMCID: PMC7979760 DOI: 10.1038/s41598-021-85250-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2020] [Accepted: 02/24/2021] [Indexed: 11/09/2022] Open
Abstract
Climate change and emerging drug resistance make the control of many infectious diseases increasingly challenging and diminish the exclusive reliance on drug treatment as sole solution to the problem. As disease transmission often depends on environmental conditions that can be modified, such modifications may become crucial to risk reduction if we can assess their potential benefit at policy-relevant scales. However, so far, the value of environmental management for this purpose has received little attention. Here, using the parasitic disease of fasciolosis in livestock in the UK as a case study, we demonstrate how mechanistic hydro-epidemiological modelling can be applied to understand disease risk drivers and the efficacy of environmental management across a large heterogeneous domain. Our results show how weather and other environmental characteristics interact to define disease transmission potential and reveal that environmental interventions such as risk avoidance management strategies can provide a valuable alternative or complement to current treatment-based control practice.
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Affiliation(s)
- Ludovica Beltrame
- Department of Civil Engineering, University of Bristol, Bristol, UK. .,Department of Agricultural and Environmental Sciences, University of Milan, Milan, Italy.
| | - Hannah Rose Vineer
- Department of Infection Biology and Microbiomes, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, UK
| | | | - Eric R Morgan
- School of Biological Sciences, Queen's University Belfast, Belfast, UK
| | | | - Thorsten Wagener
- Department of Civil Engineering, University of Bristol, Bristol, UK.,Cabot Institute for the Environment, University of Bristol, Bristol, UK.,Institute for Environmental Science and Geography, University of Potsdam, Potsdam, Germany
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8
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Shrestha S, Barratt A, Fox NJ, Vosough Ahmadi B, Hutchings MR. Financial Impacts of Liver Fluke on Livestock Farms Under Climate Change-A Farm Level Assessment. Front Vet Sci 2020; 7:564795. [PMID: 33426012 PMCID: PMC7793977 DOI: 10.3389/fvets.2020.564795] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Accepted: 11/12/2020] [Indexed: 11/13/2022] Open
Abstract
Liver fluke infection (fascioliasis) is a parasitic disease which affects the health and welfare of ruminants. It is a concern for the livestock industry and is considered as a growing threat to the industry because changing climatic conditions are projected to be more favorable to increased frequency and intensity of liver fluke outbreaks. Recent reports highlighted that the incidence and geographic range of liver fluke has increased in the UK over the last decade and estimated to increase the average risk of liver fluke in the UK due to increasing temperature and rainfall. This paper explores financial impacts of the disease with and without climate change effects on Scottish livestock farms using a farm-level economic model. The model is based on farming system analysis and uses linear programming technique to maximize farm net profit within farm resources. Farm level data from a sample of 160 Scottish livestock farms is used under a no disease baseline scenario and two disease scenarios (with and without climate change). These two disease scenarios are compared with the baseline scenario to estimate the financial impact of the disease at farm levels. The results suggest a 12% reduction in net profit on an average dairy farm compared to 6% reduction on an average beef farm under standard disease conditions. The losses increase by 2-fold on a dairy farm and 6-fold on a beef farm when climate change effects are included with disease conditions on farms. There is a large variability within farm groups with profitable farms incurring relatively lesser economic losses than non-profitable farms. There is a substantial increase in number of vulnerable farms both in dairy (+20%) and beef farms (+27%) under the disease alongside climate change conditions.
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Affiliation(s)
- Shailesh Shrestha
- Department of Rural Economy, Environment and Society, Scotland's Rural College (SRUC), Edinburgh, United Kingdom
| | - Alyson Barratt
- Department of Rural Economy, Environment and Society, Scotland's Rural College (SRUC), Edinburgh, United Kingdom
| | - Naomi J Fox
- Animal and Veterinary Sciences, Scotland's Rural College (SRUC), Edinburgh, United Kingdom
| | - Bouda Vosough Ahmadi
- The European Commission for the Control of Foot and Mouth Disease (EuFMD), Animal Production and Health Division (AGAH), Food and Agricultural Organization (FAO), Rome, Italy
| | - Mike R Hutchings
- Animal and Veterinary Sciences, Scotland's Rural College (SRUC), Edinburgh, United Kingdom
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9
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Howell AK, Williams DJL. The Epidemiology and Control of Liver Flukes in Cattle and Sheep. Vet Clin North Am Food Anim Pract 2020; 36:109-123. [PMID: 32029178 DOI: 10.1016/j.cvfa.2019.12.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Fasciola hepatica, Fasciola gigantica, and Fascioloides magna are liver flukes causing disease in cattle and sheep. Damage to the liver due to F hepatica and F gigantica results in clinical disease and/or production losses. F magna seems to have little effect in cattle but causes high mortality in sheep. The fluke life cycle involves an aquatic or amphibious snail intermediate host and thus requires suitable moisture and temperature conditions. F magna requires the presence of deer. Drug treatment is the mainstay of control and needs to be applied considering the life cycle and epidemiology of the parasite.
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Affiliation(s)
- Alison K Howell
- Institute of Infection and Global Health, University of Liverpool, Leahurst Campus, Chester High Road, Neston CH64 7TE, UK.
| | - Diana J L Williams
- Institute of Infection and Global Health, University of Liverpool, Leahurst Campus, Chester High Road, Neston CH64 7TE, UK
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10
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French AS, Zadoks RN, Skuce PJ, Mitchell G, Gordon-Gibbs DK, Taggart MA. Habitat and host factors associated with liver fluke (Fasciola hepatica) diagnoses in wild red deer (Cervus elaphus) in the Scottish Highlands. Parasit Vectors 2019; 12:535. [PMID: 31718680 PMCID: PMC6852960 DOI: 10.1186/s13071-019-3782-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Accepted: 10/30/2019] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Red deer (Cervus elaphus) are a common wild definitive host for liver fluke (Fasciola hepatica) that have been the subject of limited diagnostic surveillance. This study aimed to explore the extent to which coprological diagnoses for F. hepatica in red deer in the Scottish Highlands, Scotland, are associated with variability among hosts and habitats. METHODS Our analyses were based on coproantigen ELISA diagnoses derived from faecal samples that were collected from carcasses of culled deer on nine hunting estates during two sampling seasons. Sampling locations were used as centroids about which circular home ranges were quantified. Data were stratified by season, and associations between host, hydrological, land cover and meteorological variables and binary diagnoses during 2013-2014 (n = 390) were explored by mixed effect logistic regression. The ability of our model to predict diagnoses relative to that which would be expected by chance was quantified, and data collected during 2012-2013 (n = 289) were used to assess model transferability. RESULTS During 2013-2014, habitat and host characteristics explained 28% of variation in diagnoses, whereby half of the explained variation was attributed to differences among estates. The probability of a positive diagnosis was positively associated with the length of streams in the immediate surroundings of each sampling location, but no non-zero relationships were found for land cover or lifetime average weather variables. Regardless of habitat, the probability of a positive diagnosis remained greatest for males, although males were always sampled earlier in the year than females. A slight decrease in prediction efficacy occurred when our model was used to predict diagnoses for out-of-sample data. CONCLUSIONS We are cautious to extrapolate our findings geographically, owing to a large proportion of variation attributable to overarching differences among estates. Nevertheless, the temporal transferability of our model is encouraging. While we did not identify any non-zero relationship between meteorological variables and probability of diagnosis, we attribute this (in part) to limitations of interpolated meteorological data. Further study into non-independent diagnoses within estates and differences among estates in terms of deer management, would improve our understanding of F. hepatica prevalence in wild deer.
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Affiliation(s)
- Andrew S French
- Environmental Research Institute, North Highland College, University of the Highlands and Islands, Castle Street, Thurso, KW14 7JD, UK. .,Marine Institute, Furnace, Newport, Co. Mayo, Ireland.
| | - Ruth N Zadoks
- Institute of Biodiversity Animal Health and Comparative Medicine, University of Glasgow, Garscube Campus, Glasgow, G61 1QH, UK.,Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, EH26 0PZ, UK.,Sydney School of Veterinary Science, University of Sydney, Camden, NSW 2570, Australia
| | - Philip J Skuce
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, EH26 0PZ, UK
| | - Gillian Mitchell
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, EH26 0PZ, UK
| | | | - Mark A Taggart
- Environmental Research Institute, North Highland College, University of the Highlands and Islands, Castle Street, Thurso, KW14 7JD, UK
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11
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John BC, Davies DR, Williams DJL, Hodgkinson JE. A review of our current understanding of parasite survival in silage and stored forages, with a focus on Fasciola hepatica metacercariae. GRASS AND FORAGE SCIENCE : THE JOURNAL OF THE BRITISH GRASSLAND SOCIETY 2019; 74:211-217. [PMID: 31244499 PMCID: PMC6582591 DOI: 10.1111/gfs.12429] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Revised: 03/08/2019] [Accepted: 04/07/2019] [Indexed: 06/09/2023]
Abstract
Fasciola hepatica, the parasitic liver fluke, is a re-emerging zoonotic infection and an important cause of morbidity and mortality in ruminant livestock worldwide. A significant animal welfare concern, fasciolosis also has a detrimental impact on food security, with the effects of sub-clinical infection on growth rate and milk yield estimated to cost the UK cattle industry £40.4 million annually. It is understood that up to 50% of infective F. hepatica metacercariae may overwinter on pasture and remain viable to infect grazing livestock the following spring. However, the infection risk posed by feeding grass silage to livestock remains largely unknown as the majority of previous studies are outdated in both experimental design and analysis of ensiled metacercariae viability. Anecdotal reports of fasciolosis outbreaks in housed livestock have reignited interest in F. hepatica metacercariae survival during modern ensiling processes and more importantly if they retain viability within stored forages. Consequently, a comprehensive review of the available literature is required in order to identify knowledge gaps and highlight future research opportunities regarding the role of silage in the transmission of F. hepatica.
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Affiliation(s)
- Bethan C. John
- Institute of Infection and Global HealthUniversity of LiverpoolLiverpoolUK
| | | | | | - Jane E. Hodgkinson
- Institute of Infection and Global HealthUniversity of LiverpoolLiverpoolUK
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12
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Villa-Mancera A, Reynoso-Palomar A. High prevalence, potential economic impact, and risk factors of Fasciola hepatica in dairy herds in tropical, dry and temperate climate regions in Mexico. Acta Trop 2019; 193:169-175. [PMID: 30844375 DOI: 10.1016/j.actatropica.2019.03.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2019] [Revised: 02/02/2019] [Accepted: 03/03/2019] [Indexed: 01/06/2023]
Abstract
The aims of this study were to determine the prevalence of fasciolosis in cattle herds and its influence on production in order to identify potential risk factors in different climate regions and risk indices in three states of Mexico. The levels of anti-F. hepatica IgG1 antibodies were determined using an indirect ELISA. A total of 837 farm owners or managers answered the questionnaire. The total prevalence of the parasite over the period of January to March 2017 was 63.56%. The highest percentages of positive herds for the categories were found in Hidalgo state (88.33%), the no-risk classification (69.55%) and the temperate climate (76.53%). Overall, the production losses were approximately 0.51 to 1.00 kg of milk per parasitized cow per day. The annual costs of milk production loss per farm were estimated to range from US$2218.39 to US$6424.51, followed by anthelmintic treatment for young stock (US$67.68) and adult cows (US$209.47). Using multivariate logistic regression analysis, six final models were constructed for potential association with the ELISA results and were supported by the climatic, environmental and management factors. The results indicate that different factors were significantly associated with an increased risk of infection for each model.
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13
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Kamaludeen J, Graham-Brown J, Stephens N, Miller J, Howell A, Beesley NJ, Hodgkinson J, Learmount J, Williams D. Lack of efficacy of triclabendazole against Fasciola hepatica is present on sheep farms in three regions of England, and Wales. Vet Rec 2019; 184:502. [PMID: 30824600 PMCID: PMC6583106 DOI: 10.1136/vr.105209] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Revised: 01/19/2019] [Accepted: 01/30/2019] [Indexed: 11/04/2022]
Abstract
The liver fluke Fasciola hepatica is a parasitic trematode that has a major impact on livestock production and human health. Control of F hepatica is difficult and relies on anthelmintics, particularly triclabendazole, due to its efficacy against both adult and juvenile stages of the parasite. Emergence of triclabendazole-resistant F hepatica populations has been reported in a number of countries, including the UK, but the overall prevalence and distribution of triclabendazole resistance is unknown. In this study, the authors established the presence of reduced efficacy of triclabendazole in sheep flocks in England and Wales, using a validated composite faecal egg count reduction test. Seventy-four sheep farms were sampled from Wales, southwest, northwest and northeast England between Autumn 2013 and Spring 2015. F hepatica eggs were detected in samples from 42/74 farms. Evidence of a lack of efficacy of triclabendazole was detected on 21/26 farms on which the faecal egg count reduction test was completed, with faecal egg count reductions ranging from 89 per cent to 0per cent. Regression analysis suggested that both prevalence of F hepatica and lack of efficacy of triclabendazole were spatially correlated, with higher faecal egg counts and lower percentage reductions on farms located in the northwest of England, and Wales. Overall, the results show that reduced efficacy of triclabendazole is present across England and Wales, with a complete lack of therapeutic efficacy observed on 9/26 farms.
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Affiliation(s)
- Juriah Kamaludeen
- Faculty of Agriculture and Food Sciences, Universiti Putra Malaysia-Kampus Bintulu, Bintulu, Malaysia
| | - John Graham-Brown
- Infection Biology, University of Liverpool Institute of Infection and Global Health, Liverpool, UK
| | | | - Josephine Miller
- University of Liverpool School of Veterinary Science, Liverpool, UK
| | - Alison Howell
- Infection Biology, University of Liverpool Institute of Infection and Global Health, Liverpool, UK
| | - Nicola J Beesley
- Infection Biology, University of Liverpool Institute of Infection and Global Health, Liverpool, UK
| | | | - Jane Learmount
- United Kingdom Department for Environment Food and Rural Affairs, London, UK
| | - Diana Williams
- University of Liverpool Institute of Infection and Global Health, Liverpool, UK
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14
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Graham-Brown J, Williams DJL, Skuce P, Zadoks RN, Dawes S, Swales H, Van Dijk J. Composite Fasciola hepatica faecal egg sedimentation test for cattle. Vet Rec 2019; 184:589. [PMID: 30711919 PMCID: PMC6583716 DOI: 10.1136/vr.105128] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Revised: 12/04/2018] [Accepted: 12/28/2018] [Indexed: 11/03/2022]
Abstract
Options for diagnosing Fasciola hepatica infection in groups of cattle are limited. Increasing the opportunities for herd-level diagnosis is important for disease monitoring, making informed treatment decisions and for flukicide efficacy testing. The sensitivity of a simple sedimentation method based on composite faecal samples for the detection of fluke eggs in cattle was assessed through a combination of experimental and statistical modelling techniques. Initially, a composite sample method previously developed for sheep was used to investigate the sensitivity of composite sample testing compared with individual counts on the same samples in cattle. Following this, an optimised, validated, qualitative (presence-absence) composite sample field test was developed for cattle. Results showed that fluke egg counts obtained from a composite sample are representative of those expected from individual counts. The optimal sampling strategy was determined to be 10 individual 10 g samples (100 g composite sample) from which a 10 g subsample is taken for sedimentation. This method yielded a diagnostic sensitivity of 0.69 (95 per cent CI 0.5 to 0.85). These results demonstrate the validity and usefulness of a composite faecal egg sedimentation method for use in the diagnosis and control of F. hepatica in groups of cattle, with the caveat that a negative test should be followed up with a second test due to limitations relating to test sensitivity.
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Affiliation(s)
- John Graham-Brown
- Infection Biology, University of Liverpool Institute of Infection and Global Health, Liverpool, UK
| | - Diana J L Williams
- Infection Biology, University of Liverpool Institute of Infection and Global Health, Liverpool, UK
| | | | - Ruth N Zadoks
- Moredun Research Institute, Midlothian, UK.,University of Glasgow Institute of Biodiversity Animal Health and Comparative Medicine, Glasgow, UK
| | | | - Harry Swales
- Institute of Veterinary Science, Liverpool, Merseyside, UK
| | - Jan Van Dijk
- Epidemiology and Surveillance, Centre for Preventive Medicine, Animal Health Trust, Newmarket, Suffolk, UK
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15
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Takeuchi-Storm N, Denwood M, Petersen HH, Enemark HL, Stensgaard AS, Sengupta ME, Beesley NJ, Hodgkinson J, Williams D, Thamsborg SM. Patterns of Fasciola hepatica infection in Danish dairy cattle: implications for on-farm control of the parasite based on different diagnostic methods. Parasit Vectors 2018; 11:674. [PMID: 30594235 PMCID: PMC6310998 DOI: 10.1186/s13071-018-3248-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Accepted: 11/29/2018] [Indexed: 11/17/2022] Open
Abstract
Background Bovine fasciolosis is an economically important livestock disease in Europe, and represents a particular challenge for organic farms, where cattle are grazed extensively and the use of anthelmintic is limited. A two-year longitudinal study was conducted on two conventional and two organic Danish dairy farms to examine the current temporal trend of F. hepatica infection on-farm, and to gather data of practical relevance for parasite control. Data were collected both at the herd and individual level using currently available diagnostic methods: a commercial serum antibody ELISA, a commercial copro-antigen ELISA, faecal egg counts, and monthly bulk tank milk (BTM) ELISA. The temporal patterns (animal age, farm-level temporal trends and seasonality) in the animal-level test results were analysed by generalised additive mixed models (GAMM). Results Patterns of infection differed substantially between the farms, due to different grazing management and anthelmintic use. However, animals were first infected at the age of 1.5–2 years (heifers), and most at-risk animals sero-converted in autumn, suggesting that summer infections in snails prevail in Denmark. Our results also suggest that the lifespan of the parasite could be over 2 years, as several cows showed signs of low grade infection even after several years of continuous indoor housing without access to freshly-cut grass. The serum antibody ELISA was able to detect infection first, whereas both copro-antigen ELISA and faecal egg counts tended to increase in the same animals at a later point. Decreasing BTM antibody levels were seen on the two farms that started anthelmintic treatment during the study. Conclusions While important differences between farms and over time were seen due to varying grazing management, anthelmintic treatment and climatic conditions, the young stock was consistently seen as the main high-risk group and at least one farm also had suspected transmission (re-infection) within the lactating herd. Careful interpretation of test results is necessary for older cows as they can show persistent infections several years after exposure has stopped. Rigorous treatment regimens can reduce BTM ELISA values, but further research is needed to develop a non-medicinal approach for sustainable management of bovine fasciolosis. Electronic supplementary material The online version of this article (10.1186/s13071-018-3248-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Nao Takeuchi-Storm
- Research Group for Veterinary Parasitology, Department of Veterinary and Animal Sciences, University of Copenhagen, Dyrlægevej 100, DK-1871, Frederiksberg C, Denmark.
| | - Matthew Denwood
- Section for Animal Welfare and Disease Control, Department of Veterinary and Animal Sciences, University of Copenhagen, Grønnegårdsvej 8, DK-1870, Frederiksberg C, Denmark
| | - Heidi Huus Petersen
- National Veterinary Institute, Technical University of Denmark, Kemitorvet, DK-2800, Kongens Lyngby, Denmark
| | - Heidi Larsen Enemark
- Research Group for Animal Health, Department of Animal Health and Food Safety, Norwegian Veterinary Institute, P.O. Box 750, Sentrum, NO-0106, Oslo, Norway
| | - Anna-Sofie Stensgaard
- Center for Macroecology, Evolution and Climate, The Natural History Museum of Denmark, University of Copenhagen, Universitetsparken 15, DK-2100, København Ø, Denmark
| | - Mita Eva Sengupta
- Center for Macroecology, Evolution and Climate, The Natural History Museum of Denmark, University of Copenhagen, Universitetsparken 15, DK-2100, København Ø, Denmark
| | - Nicola Jane Beesley
- Department of Infection Biology, Institute of Infection and Global Health, University of Liverpool, Liverpool Science Park IC2, 146 Brownlow Hill, Liverpool, L3 5RF, UK
| | - Jane Hodgkinson
- Department of Infection Biology, Institute of Infection and Global Health, University of Liverpool, Liverpool Science Park IC2, 146 Brownlow Hill, Liverpool, L3 5RF, UK
| | - Diana Williams
- Department of Infection Biology, Institute of Infection and Global Health, University of Liverpool, Liverpool Science Park IC2, 146 Brownlow Hill, Liverpool, L3 5RF, UK
| | - Stig Milan Thamsborg
- Research Group for Veterinary Parasitology, Department of Veterinary and Animal Sciences, University of Copenhagen, Dyrlægevej 100, DK-1871, Frederiksberg C, Denmark
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16
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Bulk tank milk ELISA to detect IgG1 prevalence and clustering to determine spatial distribution and risk factors of Fasciola hepatica-infected herds in Mexico. J Helminthol 2018; 93:704-710. [DOI: 10.1017/s0022149x18000792] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
AbstractFasciola hepatica is a helminth parasite that causes huge economic losses to the livestock industry worldwide. Fasciolosis is an emerging foodborne zoonotic disease that affects both humans and grazing animals. This study investigated the associations between climatic/environmental factors (derived from satellite data) and management factors affecting the spatial distribution of this liver fluke in cattle herds across different climate zones in three Mexican states. A bulk-tank milk (BTM) IgG1 enzyme-linked immunosorbent assay (ELISA) test was used to detect F. hepatica infection levels of 717 cattle herds between January and April 2015. Management data were collected from the farms by questionnaire. The parasite's overall herd prevalence and mean optical density ratio (ODR) were 62.76% and 0.67, respectively. The presence of clustered F. hepatica infections was studied using the spatial scan statistic. Three marked clusters in the spatial distribution of the parasite were observed. Logistic regression was used to test three models of potential statistical association from the ELISA results using climatic, environmental and management variables. The final model based on climatic/environmental and management variables included the following factors: rainfall, elevation, proportion of grazed grass in the diet, contact with other herds, herd size, parasite control use and education level as significant predictors. Geostatistical kriging was applied to generate a risk map for the presence of parasites in dairy herds in Mexico. In conclusion, the spatial distribution of F. hepatica in Mexican cattle herds is influenced by multifactorial effects and should be considered in developing regionally adapted control measures.
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17
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Hodgkinson JE, Cwiklinski K, Beesley N, Hartley C, Allen K, Williams DJL. Clonal amplification of Fasciola hepatica in Galba truncatula: within and between isolate variation of triclabendazole-susceptible and -resistant clones. Parasit Vectors 2018; 11:363. [PMID: 29941045 PMCID: PMC6020221 DOI: 10.1186/s13071-018-2952-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Accepted: 06/13/2018] [Indexed: 11/10/2022] Open
Abstract
Background Fasciola hepatica is of worldwide significance, impacting on the health, welfare and productivity of livestock and regarded by WHO as a re-emerging zoonosis. Triclabendazole (TCBZ), the drug of choice for controlling acute fasciolosis in livestock, is also the drug used to treat human infections. However TCBZ-resistance is now considered a major threat to the effective control of F. hepatica. It has yet to be demonstrated whether F. hepatica undergoes a genetic clonal expansion in the snail intermediate host, Galba truncatula, and to what extent amplification of genotypes within the snail facilitates accumulation of drug resistant parasites. Little is known about genotypic and phenotypic variation within and between F. hepatica isolates. Results Six clonal isolates of F. hepatica (3× triclabendazole-resistant, TCBZ-R and 3× triclabendazole-susceptible, TCBZ-S) were generated. Snails infected with one miracidium started to shed cercariae 42–56 days post-infection and shed repeatedly up to a maximum of 11 times. A maximum of 884 cercariae were shed by one clonally-infected snail (FhLivS1) at a single time point, with > 3000 clonal metacercariae shed over its lifetime. Following experimental infection all 12 sheep were FEC positive at the time of TCBZ treatment. Sheep infected with one of three putative TCBZ-S clones and treated with TCBZ had no parasites in the liver at post-mortem, whilst sheep each infected with putative TCBZ-R isolates had 35–165 adult fluke at post-mortem, despite TCBZ treatment. All six untreated control animals had between 15–127 parasites. A single multi-locus genotype was reported for every fluke from each of the six clonal isolates. Adult F. hepatica showed considerable variation in weight, ranging from 20–280 mg, with variation in weight evident within and amongst clonal isolates. Conclusions A genetic clonal expansion occurs within G. truncatula, highlighting the potential for amplification of drug resistant genotypes of F. hepatica. Variation in the weight of parasites within and between clonal isolates and when comparing isolates that are either susceptible or resistant to TCBZ represent inherent variation in liver fluke and cannot be attributed to their resistance or susceptibility traits.
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Affiliation(s)
- Jane E Hodgkinson
- Veterinary Parasitology, Dept Infection Biology, Institute of Infection and Global Health, University of Liverpool, Liverpool, L69 7ZJ, UK.
| | - Krystyna Cwiklinski
- Veterinary Parasitology, Dept Infection Biology, Institute of Infection and Global Health, University of Liverpool, Liverpool, L69 7ZJ, UK.,School of Biological Sciences, Medical Biology Centre, Queen's University Belfast, Belfast, BT9 7BL, UK
| | - Nicola Beesley
- Veterinary Parasitology, Dept Infection Biology, Institute of Infection and Global Health, University of Liverpool, Liverpool, L69 7ZJ, UK
| | - Catherine Hartley
- Veterinary Parasitology, Dept Infection Biology, Institute of Infection and Global Health, University of Liverpool, Liverpool, L69 7ZJ, UK
| | - Katherine Allen
- Veterinary Parasitology, Dept Infection Biology, Institute of Infection and Global Health, University of Liverpool, Liverpool, L69 7ZJ, UK
| | - Diana J L Williams
- Veterinary Parasitology, Dept Infection Biology, Institute of Infection and Global Health, University of Liverpool, Liverpool, L69 7ZJ, UK
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18
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McCann CM, Clough HE, Baylis M, Williams DJL. Development and validation of a protocol to identify and recruit participants into a large scale study on liver fluke in cattle. BMC Vet Res 2018; 14:185. [PMID: 29907108 PMCID: PMC6003166 DOI: 10.1186/s12917-018-1511-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Accepted: 05/31/2018] [Indexed: 11/10/2022] Open
Abstract
Background Liver fluke infection caused by the parasite Fasciola hepatica is a major cause of production losses to the cattle industry in the UK. To investigate farm-level risk factors for fluke infection, a randomised method to recruit an appropriate number of herds from a defined geographical area into the study was required. The approach and hurdles that were encountered in designing and implementing this study are described. The county of Shropshire, England, was selected for the study because of the variation between farms in exposure to fluke infection observed in an earlier study. Results From a sampling list of 569 holdings in Shropshire randomly drawn from the RADAR cattle population dataset, 396 (69.6%) holdings were successfully contacted by telephone and asked if they would be interested in taking part in the study. Of 296 farmers who agreed to receive information packs by post, 195 (65.9%) agreed to take part in the study. Over the period October 2014 – April 2015 visits were made to 100 dairy and 95 non-dairy herds. During the farm visits 40 faecal samples +/− bulk-tank milk samples were collected and a questionnaire administered. Composite faecal samples were analysed for the presence of F. hepatica eggs by sedimentation and bulk tank milk samples were tested with an antibody ELISA for F. hepatica. Forty-five (49%) of non-dairy herds were positive for liver fluke infection as determined by the finding of one or more fluke eggs, while 36 (36%) dairy herds had fluke positive faecal samples and 41 (41%) dairy herds were positive for F. hepatica antibody. Eighty-seven (45.8%) farmers said that they monitored their cattle for liver fluke infection and 118 (62.1%) reported that they used flukicide drugs in their cattle. Conclusions Using a protocol of contacting farmers directly by telephone and subsequently sending information by post, 79% of the target sample size was successfully recruited into the study. A dataset of farm-specific information on possible risk factors for liver fluke infection and corresponding liver-fluke infection status was generated for the development of statistical models to identify risk factors for liver fluke infection at the farm-level.
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Affiliation(s)
- Catherine M McCann
- Department of Infection Biology, Institute of Infection and Global Health, University of Liverpool, Liverpool, UK. .,Present address: Epidemiology Research Unit, Scotland's Rural College (SRUC), An Lòchran, Inverness Campus, Inverness, IV2 5NA, UK.
| | - Helen E Clough
- Department of Infection Biology, Institute of Infection and Global Health, University of Liverpool, Liverpool, UK.,Department of Public Health and Policy, Institute of Psychology, Health and Society, University of Liverpool, Liverpool, UK
| | - Matthew Baylis
- National Institute of Health Research Health Protection Research Unit in Emerging and Zoonotic Infections, University of Liverpool, Liverpool, UK.,Department of Epidemiology and Population Health, Institute of Infection and Global Health, University of Liverpool, Liverpool, UK
| | - Diana J L Williams
- Department of Infection Biology, Institute of Infection and Global Health, University of Liverpool, Liverpool, UK
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19
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Byrne AW, Graham J, McConville J, Milne G, McDowell S, Hanna REB, Guelbenzu-Gonzalo M. Seasonal variation of Fasciola hepatica antibodies in dairy herds in Northern Ireland measured by bulk tank milk ELISA. Parasitol Res 2018; 117:2725-2733. [PMID: 29948207 DOI: 10.1007/s00436-018-5961-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Accepted: 06/05/2018] [Indexed: 11/28/2022]
Abstract
Bovine fasciolosis, caused by the infection of the trematode parasite Fasciola hepatica, remains a problem in dairy herds causing significant production losses. In this study, bulk milk tank samples were utilised to generate a comprehensive survey of the variation in liver fluke exposure over the four seasons of 2016 in Northern Ireland (NI). Samples were tested using an antibody ELISA test; within-herd prevalence levels were categorised relative to sample-to-positive ratio (S/P%). Overall, 1494 herds (~ 50% of all active dairy farms in NI) were sampled. In total, 5750 samples were tested with 91% of herds having a sample result for each season. The proportion of herds with evidence of liver fluke exposure was very high across the year, with 93.03% of all bulk milk samples having some indication of liver fluke antibody presence. A high proportion of samples (2187/5750; 38.03%) fell within the highest infection class (indicating high within-herd prevalence). There was significant seasonal variation in the mean S/P%. A multivariable random effect ordinal logit model suggested that the greatest probability of being in a higher infection class was in winter, whilst the lowest was recorded during summer. There was a significant negative association between increasing herd liver fluke infection class and herd size. Furthermore, there was significant variation in infection levels across regions of Northern Ireland, with higher infection levels in northern administrative areas. This study demonstrates the very high liver fluke exposure in this region of Europe, and that risk is not equally distributed spatially or across seasons in dairy herds.
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Affiliation(s)
- Andrew W Byrne
- Agri-food and Biosciences Institute, Veterinary Science Division, Stormont, Belfast, UK. .,School of Biological Sciences, Queens University Belfast, Belfast, UK.
| | - Jordon Graham
- Agri-food and Biosciences Institute, Veterinary Science Division, Stormont, Belfast, UK
| | - James McConville
- Agri-food and Biosciences Institute, Veterinary Science Division, Stormont, Belfast, UK
| | - Georgina Milne
- Agri-food and Biosciences Institute, Veterinary Science Division, Stormont, Belfast, UK
| | - Stanley McDowell
- Agri-food and Biosciences Institute, Veterinary Science Division, Stormont, Belfast, UK
| | - Robert E B Hanna
- Agri-food and Biosciences Institute, Veterinary Science Division, Stormont, Belfast, UK
| | - Maria Guelbenzu-Gonzalo
- Agri-food and Biosciences Institute, Veterinary Science Division, Stormont, Belfast, UK. .,Animal Health Ireland, Carrick-on-Shannon, Leitrim, Ireland.
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20
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Bellet C, Green M, Bradley A, Kaler J. Short- and long-term association between individual levels of milk antibody against Ostertagia ostertagi and first-lactation heifer’s production performances. Vet Parasitol 2018; 256:1-8. [DOI: 10.1016/j.vetpar.2018.04.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Revised: 04/09/2018] [Accepted: 04/14/2018] [Indexed: 10/17/2022]
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21
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Mochankana ME, Robertson ID. Cross-sectional prevalence of Fasciola gigantica infections in beef cattle in Botswana. Trop Anim Health Prod 2018; 50:1355-1363. [PMID: 29700731 DOI: 10.1007/s11250-018-1568-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Accepted: 03/06/2018] [Indexed: 10/17/2022]
Abstract
A cross-sectional study was carried out to determine the prevalence and distribution of Fasciola gigantica infections in communally grazed and ranch-grazed beef cattle through coprological examination. A total of 8646 cattle (4618 adults, 2843 weaners and 1185 calves) faecal samples were collected during the 24 months of study. Results from this study indicated that only 64 (0.74%; 95% CI 0.57, 0.94%) of the samples were positive for F. gigantica eggs. The positive samples were detected in one (Central) of the six study districts and was restricted to the Tuli Block (commercial) farms in Machaneng village in eastern Botswana. The prevalence of fluke eggs was significantly higher in adult cattle (12.85%; 95% CI 9.72, 16.54%) than weaners (6.49%; 95% CI 3.40, 11.06%) and calves (0.79%; 95% CI 0.02, 4.31%), (χ2(2) = 19.01, p < 0.001). Thus, adults (OR = 18.57; 95% CI 2.54, 135.81%) were approximately 20 times more likely to be infected than calves. By taking liver inspection as a gold standard for diagnosis of fasciolosis, the sensitivity of the sedimentation technique was found to be 72.41% and the specificity 100%, with moderate relationship (κ = 0.53; 95% CI 0.31-0.75) between the two methods. This study has demonstrated that infection of cattle from Botswana, with F. gigantica, was low and distribution of the fluke appeared to be linked to suitable environmental conditions for the intermediate host snail. However, detailed surveillance studies, involving more cattle and areas, are required to verify the true prevalence. Such information would assist in the design of appropriate, strategic and effective fluke control programmes.
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Affiliation(s)
- M Ernest Mochankana
- College of Veterinary Medicine, School of Veterinary and Life Sciences, Murdoch University, Perth, Western Australia, 6150, Australia. .,Botswana University of Agriculture and Natural Resources, Content Farm, Sebele, Gaborone, Botswana.
| | - Ian D Robertson
- College of Veterinary Medicine, School of Veterinary and Life Sciences, Murdoch University, Perth, Western Australia, 6150, Australia
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22
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Takeuchi-Storm N, Denwood M, Hansen TVA, Halasa T, Rattenborg E, Boes J, Enemark HL, Thamsborg SM. Farm-level risk factors for Fasciola hepatica infection in Danish dairy cattle as evaluated by two diagnostic methods. Parasit Vectors 2017; 10:555. [PMID: 29121986 PMCID: PMC5679181 DOI: 10.1186/s13071-017-2504-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Accepted: 10/29/2017] [Indexed: 11/10/2022] Open
Abstract
Background The prevalence of bovine fasciolosis in Denmark is increasing but appropriate guidelines for control are currently lacking. In order to help develop a control strategy for liver fluke, a risk factor study of farm management factors was conducted and the utility of bulk tank milk (BTM ELISA) as a tool for diagnosis in Danish dairy cattle farms was assessed. Methods This case-control study aimed to identify farm-level risk factors for fasciolosis in Danish dairy farms (> 50 animals slaughtered in 2013) using two diagnostic methods: recordings of liver condemnation at slaughter, and farm-level Fasciola hepatica antibody levels in BTM. A case farm was defined as having a minimum of 3 incidents of liver condemnation due to liver fluke at slaughter (in any age group) during 2013, and control farms were located within 10 km of at least one case farm and had no history of liver condemnation due to liver fluke during 2011–2013. The selected farmers were interviewed over telephone about grazing and control practices, and BTM from these farms was collected and analysed by ELISA in 2014. The final complete dataset consisting of 131 case and 63 control farms was analysed using logistic regression. Results Heifers grazing on wet pastures, dry cows grazing on wet pastures, herd size, breed and concurrent beef cattle production were identified as risk factors associated with being classified as a case farm. With the categorised BTM ELISA result as the response variable, heifers grazing on wet pastures, dry cows grazing on wet pastures, and purchase of cows were identified as risk factors. Within the case and control groups, 74.8 and 12.7% of farms were positive for fasciolosis on BTM ELISA, respectively. The differences are likely to be related to the detection limit of the farm-level prevalence by the BTM ELISA test, time span between slaughter data and BTM, and the relatively low sensitivity of liver inspection at slaughter. Conclusions Control of bovine fasciolosis in Denmark should target heifers and dry cows through grazing management and appropriate anthelmintic treatment, and BTM ELISA can be a useful diagnostic tool for fasciolosis in Danish dairy farms. Electronic supplementary material The online version of this article (10.1186/s13071-017-2504-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Nao Takeuchi-Storm
- Department of Veterinary and Animal Sciences, Research Group for Veterinary Parasitology, University of Copenhagen, Dyrlægevej 100, DK-1871, Frederiksberg C, Denmark.
| | - Matthew Denwood
- Department of Veterinary and Animal Sciences, Section for Animal Welfare and Disease Control, University of Copenhagen, Grønnegårdsvej 8, DK-1870, Frederiksberg C, Denmark
| | - Tina Vicky Alstrup Hansen
- Department of Veterinary and Animal Sciences, Research Group for Veterinary Parasitology, University of Copenhagen, Dyrlægevej 100, DK-1871, Frederiksberg C, Denmark
| | - Tariq Halasa
- National Veterinary Institute, Technical University of Denmark, Kemitorvet Building 204, DK-2800, Kgs. Lyngby, Denmark
| | - Erik Rattenborg
- SEGES, Landbrug & Fødevarer F.m.b.A, Agro Food Park 15, DK-8200, Aarhus N, Denmark
| | - Jaap Boes
- SEGES, Landbrug & Fødevarer F.m.b.A, Agro Food Park 15, DK-8200, Aarhus N, Denmark
| | - Heidi Larsen Enemark
- Section for Parasitology, Norwegian Veterinary Institute, P.O. Box 750, Sentrum, NO-0106, Oslo, Norway
| | - Stig Milan Thamsborg
- Department of Veterinary and Animal Sciences, Research Group for Veterinary Parasitology, University of Copenhagen, Dyrlægevej 100, DK-1871, Frederiksberg C, Denmark
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Rumen fluke (Calicophoron daubneyi) on Welsh farms: prevalence, risk factors and observations on co-infection with Fasciola hepatica. Parasitology 2017; 144:237-247. [PMID: 28145217 PMCID: PMC5300002 DOI: 10.1017/s0031182016001797] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Reports of Calicophoron daubneyi infecting livestock in Europe have
increased substantially over the past decade; however, there has not been an estimate of
its farm level prevalence and associated risk factors in the UK. Here, the prevalence of
C. daubneyi across 100 participating Welsh farms was recorded, with
climate, environmental and management factors attained for each farm and used to create
logistic regression models explaining its prevalence. Sixty-one per cent of farms studied
were positive for C. daubneyi, with herd-level prevalence for cattle
(59%) significantly higher compared with flock-level prevalence for sheep (42%,
P = 0·029). Co-infection between C. daubneyi and
Fasciola hepatica was observed on 46% of farms; however, a significant
negative correlation was recorded in the intensity of infection between each parasite
within cattle herds (rho = −0·358, P = 0·007). Final models showed
sunshine hours, herd size, treatment regularity against F. hepatica, the
presence of streams and bog habitats, and Ollerenshaw index values as significant positive
predictors for C. daubneyi (P < 0·05). The
results raise intriguing questions regarding C. daubneyi epidemiology,
potential competition with F. hepatica and the role of climate change in
C. daubneyi establishment and its future within the UK.
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24
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Jiménez-Rocha AE, Argüello-Vargas S, Romero-Zuñiga JJ, Sequeira-Avalos JA, Dolz G, Montenegro-Hidalgo V, Schnieder T. Environmental factors associated with Dictyocaulus viviparus and Fasciola hepatica prevalence in dairy herds from Costa Rica. VETERINARY PARASITOLOGY- REGIONAL STUDIES AND REPORTS 2017; 9:115-121. [PMID: 31014833 DOI: 10.1016/j.vprsr.2017.06.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Revised: 05/31/2017] [Accepted: 06/13/2017] [Indexed: 11/29/2022]
Abstract
Dictyocaulosis and fasciolosis are parasitic diseases that cause considerable economic losses for owners of farm animals worldwide, with special relevance on fasciolosis because it is an emerging zoonosis. Indirect diagnosis of these diseases through analyses of bulk milk tank samples has allowed carrying out large-scale prevalence studies, while the use of geographical information systems has helped to visualize and determine those variables that affect distribution of these pathogens. This study is intended to describe the spatial distribution of Dictyocaulus viviparus and Fasciola hepatica in dairy herds from Costa Rica, as well as their associated environmental factors. Bulk milk tank samples from 526 dairy herds in the three most important dairy regions of Costa Rica were analyzed using enzyme immunoassays. Results from the farms were subjected to spatial analyses using Holdridge's life zones, relief and soil type environmental layers. Of the total bulk milk tank samples analyzed, 3.8% (n=20) and 3.6% (n=19) were positive for D. viviparus and F. hepatica, respectively. Moran's I analysis revealed the existence of potential cluster (Moran's I=1.789, z=12.726 p<0.05) for D. viviparus. Consequently, Getis-Ord General G analysis showed that the spatial distribution of positive farms in the dataset was clustered (Observed General G=0.015, variance=0.000001, z=12.823, p<0.05). No significant positive spatial autocorrelation (Moran's I=0.038, z=0.286, p>0.0.5) was observed for F. hepatica. Furthermore, a significant difference was detected in the spatial locations of both parasites (latitude p<0.05, longitude p<0.05), and about the spatial distribution of both D. viviparus negative and positive farms (latitude p<0.05, longitude p<0.05), as well as in F. hepatica negative and positive farms regarding on latitude (p<0.05), but not on longitude (p>0.05). In the case of environmental factors, significant differences were found for D. viviparus and F. hepatica with respect to types of soil, precipitation, altitudinal belts, life zones, biotemperature, and elevation.
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Affiliation(s)
- A E Jiménez-Rocha
- Laboratorio de Parasitología, Escuela de Medicina Veterinaria, Universidad Nacional, Costa Rica, P.O. Box 86-3000, Heredia, Costa Rica.
| | - S Argüello-Vargas
- Posgrado Regional en Ciencias Veterinarias Tropicales, Universidad Nacional, Costa Rica, P.O. Box 86-3000, Heredia, Costa Rica
| | - J J Romero-Zuñiga
- Programa de Investigación en Medicina Poblacional, Escuela de Medicina Veterinaria, Universidad Nacional, Costa Rica, P.O. Box 86-3000, Heredia, Costa Rica
| | - J A Sequeira-Avalos
- Cooperativa de Productores de Leche Dos Pinos, RL. Alajuela, Costa Rica, P.O. Box, 179-4060, Alajuela, Costa Rica
| | - G Dolz
- Programa de Investigación en Medicina Poblacional, Escuela de Medicina Veterinaria, Universidad Nacional, Costa Rica, P.O. Box 86-3000, Heredia, Costa Rica
| | - V Montenegro-Hidalgo
- Laboratorio de Parasitología, Escuela de Medicina Veterinaria, Universidad Nacional, Costa Rica, P.O. Box 86-3000, Heredia, Costa Rica
| | - T Schnieder
- Institute for Parasitology, University of Veterinary Medicine Hannover, Hannover, Germany
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25
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Ploeger HW, Ankum L, Moll L, van Doorn DCK, Mitchell G, Skuce PJ, Zadoks RN, Holzhauer M. Presence and species identity of rumen flukes in cattle and sheep in the Netherlands. Vet Parasitol 2017; 243:42-46. [PMID: 28807308 DOI: 10.1016/j.vetpar.2017.06.009] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Revised: 05/12/2017] [Accepted: 06/07/2017] [Indexed: 11/17/2022]
Abstract
The purpose of the study was to gain knowledge about the prevalence and identity of rumen flukes (RF) in cattle and sheep in the Netherlands. Routine faecal examinations of diagnostic submissions between May 2009 and September 2014 showed a mean annual herd or flock RF prevalence of 15.8% for cattle and 8.0% for sheep. Prevalence in cattle was higher after 2012 than before, which may reflect a change in detection method as well as an increase in true prevalence. During November and December 2014, an abattoir survey was conducted to allow for scoring of rumen fluke burden and to obtain specimens for molecular species characterization. Over 8 visits to 5 abattoirs in areas deemed to pose a high risk for trematode infection, 116 cows and 41 sheep from 27 herds and 10 flocks were examined. Prevalence of RF was higher in beef cattle than in dairy cattle and higher in cattle than in sheep. Median fluke burden was >100 specimens per animal for most positive animals. Using a semi-quantitative RF density score as a gold standard, sensitivity and specificity of a modified quantitative Dorsman egg counting method were estimated at 82.6% and 83.3%, respectively. Of 14 collected adult rumen flukes, twelve (8 bovine and 4 ovine specimens) were identified as Calicophoron daubneyi. The other two, of bovine origin, were identified as Paramphistomum leydeni, which was unexpected as in other European countries all recently collected rumen flukes in both cattle and sheep were identified as C. daubneyi. The findings implicate that multiple rumen fluke species, intermediate host species and transmission cycles may play a role in rumen fluke infections in the Netherlands.
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Affiliation(s)
- H W Ploeger
- Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584 CL Utrecht, The Netherlands
| | - L Ankum
- Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584 CL Utrecht, The Netherlands
| | - L Moll
- GD Animal Health, P.O. Box 9, 7400 AA, Deventer, The Netherlands
| | - D C K van Doorn
- Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584 CL Utrecht, The Netherlands; GD Animal Health, P.O. Box 9, 7400 AA, Deventer, The Netherlands
| | - G Mitchell
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik EH26 0PZ, United Kingdom
| | - P J Skuce
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik EH26 0PZ, United Kingdom
| | - R N Zadoks
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik EH26 0PZ, United Kingdom; Institute of Biodiversity Animal Health and Comparative Medicine, College of Medical Veterinary and Life Sciences, University of Glasgow, Glasgow G61 1QH, United Kingdom
| | - M Holzhauer
- GD Animal Health, P.O. Box 9, 7400 AA, Deventer, The Netherlands.
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26
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Mehmood K, Zhang H, Sabir AJ, Abbas RZ, Ijaz M, Durrani AZ, Saleem MH, Ur Rehman M, Iqbal MK, Wang Y, Ahmad HI, Abbas T, Hussain R, Ghori MT, Ali S, Khan AU, Li J. A review on epidemiology, global prevalence and economical losses of fasciolosis in ruminants. Microb Pathog 2017; 109:253-262. [PMID: 28602837 DOI: 10.1016/j.micpath.2017.06.006] [Citation(s) in RCA: 157] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2017] [Revised: 06/05/2017] [Accepted: 06/06/2017] [Indexed: 11/18/2022]
Abstract
Fasciolosis is an important plant borne trematode zoonosis in ruminants caused by the Fasciola hepatica and Fasciola gigentica, It is classified as a neglected tropical disease and found in more than 50 countries especially where sheep and cattle are reared. Fasciolosis is a serious animal health problems in many rural and urban areas of world, causing significant financial losses due to decrease in production and viscera condemnation in animals. Accurate diagnosis of fasciolosis is always remained a challenging task for the field practitioners. There is no comprehensive summary on the occurrence and distribution of the infection at international level. Therefore, we intended to provide a complete overview on the prevalence and epidemiology of fasciolosis in farm animals from a global prospective. It includes to map the global distribution of fasciolosis in different areas of the world to identify the endemic regions which may be a source of potential disease outbreak. The financial liability related to fasciolosis on the livestock production has also been addressed. For this purpose, the published data during 2000-2015 (15 years) on fasciolosis was reviewed and collected by electronic literature search of four databases including Google, PubMed, Science Direct, and Web of Science. Data presented are contemplated to enhance our current understanding of the parasite's geographical distribution, host range, and economic losses. Information provided would be useful for the application of more effective control strategies against fasciolosis in different geo-economics regions of the world.
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Affiliation(s)
- Khalid Mehmood
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, PR China; University College of Veterinary & Animal Sciences, Islamia University of Bahawalpur, 63100, Pakistan.
| | - Hui Zhang
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Ahmad Jawad Sabir
- Faculty of Veterinary and Agricultural Sciences, University of Melbourne, Werribe, Victoria 3030, Australia
| | - Rao Zahid Abbas
- Department of Parasitology, Faculty of Veterinary Science, University of Agriculture, Faisalabad, 38000, Pakistan.
| | - Muhammad Ijaz
- Department of Clinical Medicine and Surgery, University of Veterinary and Animal Sciences, Lahore 54000, Pakistan
| | - Aneela Zameer Durrani
- Department of Clinical Medicine and Surgery, University of Veterinary and Animal Sciences, Lahore 54000, Pakistan
| | - Muhammad Hassan Saleem
- Department of Clinical Medicine and Surgery, University of Veterinary and Animal Sciences, Lahore 54000, Pakistan
| | - Mujeeb Ur Rehman
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Muhammad Kashif Iqbal
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Yajing Wang
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Hafiz Ishfaq Ahmad
- Key Laboratory of Animal Genetics, Breeding and Reproduction, College of Animal Science and Technology, Huazhong Agricultural University, Huebi, Wuhan 430070, PR China
| | - Tariq Abbas
- University College of Veterinary & Animal Sciences, Islamia University of Bahawalpur, 63100, Pakistan
| | - Riaz Hussain
- University College of Veterinary & Animal Sciences, Islamia University of Bahawalpur, 63100, Pakistan
| | - Muhammad Taslim Ghori
- University College of Veterinary & Animal Sciences, Islamia University of Bahawalpur, 63100, Pakistan
| | - Sadaqat Ali
- University College of Veterinary & Animal Sciences, Islamia University of Bahawalpur, 63100, Pakistan
| | - Aman Ullah Khan
- College of Veterinary & Animal Sciences Jhang, Sub-Campus of University of Veterinary and Animal Sciences, Lahore 54000, Pakistan
| | - Jiakui Li
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, PR China; College of Animals Husbandry and Veterinary Medicine, Tibet Agricultural and Animal Husbandry University, Linzhi, Tibet 860000, PR China.
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27
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Innocent GT, Gilbert L, Jones EO, McLeod JE, Gunn G, McKendrick IJ, Albon SD. Combining Slaughterhouse Surveillance Data with Cattle Tracing Scheme and Environmental Data to Quantify Environmental Risk Factors for Liver Fluke in Cattle. Front Vet Sci 2017; 4:65. [PMID: 28534030 PMCID: PMC5421147 DOI: 10.3389/fvets.2017.00065] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Accepted: 04/20/2017] [Indexed: 11/25/2022] Open
Abstract
Liver fluke infection causes serious disease (fasciolosis) in cattle and sheep in many regions of the world, resulting in production losses and additional economic consequences due to condemnation of the liver at slaughter. Liver fluke depends on mud snails as an intermediate host and infect livestock when ingested through grazing. Therefore, environmental factors play important roles in infection risk and climate change is likely to modify this. Here, we demonstrate how slaughterhouse data can be integrated with other data, including animal movement and climate variables to identify environmental risk factors for liver fluke in cattle in Scotland. We fitted a generalized linear mixed model to the data, with exposure-weighted random and fixed effects, an approach which takes into account the amount of time cattle spent at different locations, exposed to different levels of risk. This enabled us to identify an increased risk of liver fluke with increased animal age, rainfall, and temperature and for farms located further to the West, in excess of the risk associated with a warmer, wetter climate. This model explained 45% of the variability in liver fluke between farms, suggesting that the unexplained 55% was due to factors not included in the model, such as differences in on-farm management and presence of wet habitats. This approach demonstrates the value of statistically integrating routinely recorded slaughterhouse data with other pre-existing data, creating a powerful approach to quantify disease risks in production animals. Furthermore, this approach can be used to better quantify the impact of projected climate change on liver fluke risk for future studies.
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Affiliation(s)
| | | | - Edward O Jones
- The James Hutton Institute, Aberdeen, UK.,Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, UK
| | | | - George Gunn
- Future Farming Systems, R&D Division, SRUC, An Lòchran - Inverness Campus, Inverness, UK
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28
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Bellet C, Green M, Vickers M, Forbes A, Berry E, Kaler J. Ostertagia spp ., rumen fluke and liver fluke single- and poly-infections in cattle: An abattoir study of prevalence and production impacts in England and Wales. Prev Vet Med 2016; 132:98-106. [DOI: 10.1016/j.prevetmed.2016.08.010] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Revised: 08/24/2016] [Accepted: 08/29/2016] [Indexed: 11/26/2022]
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29
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Kelley JM, Elliott TP, Beddoe T, Anderson G, Skuce P, Spithill TW. Current Threat of Triclabendazole Resistance in Fasciola hepatica. Trends Parasitol 2016; 32:458-469. [PMID: 27049013 DOI: 10.1016/j.pt.2016.03.002] [Citation(s) in RCA: 184] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Revised: 02/18/2016] [Accepted: 03/03/2016] [Indexed: 01/07/2023]
Abstract
Triclabendazole (TCBZ) is the only chemical that kills early immature and adult Fasciola hepatica (liver fluke) but widespread resistance to the drug greatly compromises fluke control in livestock and humans. The mode of action of TCBZ and mechanism(s) underlying parasite resistance to the drug are not known. Due to the high prevalence of TCBZ resistance (TCBZ-R), effective management of drug resistance is now critical for sustainable livestock production. Here, we discuss the current status of TCBZ-R in F. hepatica, the global distribution of resistance observed in livestock, the possible mechanism(s) of drug action, the proposed mechanisms and genetic basis of resistance, and the prospects for future control of liver fluke infections using an integrated parasite management (IPM) approach.
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Affiliation(s)
- Jane M Kelley
- Department of Animal, Plant and Soil Sciences and Centre for AgriBioscience, La Trobe University, Bundoora, VIC, Australia
| | | | - Travis Beddoe
- Department of Animal, Plant and Soil Sciences and Centre for AgriBioscience, La Trobe University, Bundoora, VIC, Australia
| | | | - Philip Skuce
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Midlothian, UK
| | - Terry W Spithill
- Department of Animal, Plant and Soil Sciences and Centre for AgriBioscience, La Trobe University, Bundoora, VIC, Australia.
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30
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Williams DJL, Hodgkinson JE. Fasciolosis in horses: A neglected, re-emerging disease. EQUINE VET EDUC 2015. [DOI: 10.1111/eve.12521] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- D. J. L. Williams
- Veterinary Parasitology; Institute of Infection and Global Health; University of Liverpool; UK
| | - J. E. Hodgkinson
- Veterinary Parasitology; Institute of Infection and Global Health; University of Liverpool; UK
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31
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van Klink EG, Prestmo PG, Grist A. Animal health and disease monitoring in the abattoir. ACTA ACUST UNITED AC 2015. [DOI: 10.12968/live.2015.20.6.330] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Ed G.M. van Klink
- Senior Lecturer Veterinary Public Health, School of Veterinary Science, University of Bristol
| | - Pia Gjertsen Prestmo
- Senior Clinical Training Scholar ECVPH, School of Veterinary Science, University of Bristol
| | - Andrew Grist
- Lecturer Veterinary Public Health, School of Veterinary Science, University of Bristol
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32
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Howell A, Baylis M, Smith R, Pinchbeck G, Williams D. Epidemiology and impact of Fasciola hepatica exposure in high-yielding dairy herds. Prev Vet Med 2015; 121:41-8. [PMID: 26093971 PMCID: PMC4528078 DOI: 10.1016/j.prevetmed.2015.05.013] [Citation(s) in RCA: 79] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2014] [Revised: 05/29/2015] [Accepted: 05/31/2015] [Indexed: 11/25/2022]
Abstract
The liver fluke Fasciola hepatica is a trematode parasite with a worldwide distribution and is the cause of important production losses in the dairy industry. The aim of this observational study was to assess the prevalence of exposure to F. hepatica in a group of high yielding dairy herds, to determine the risk factors and investigate their associations with production and fertility parameters. Bulk milk tank samples from 606 herds that supply a single retailer with liquid milk were tested with an antibody ELISA for F. hepatica. Multivariable linear regression was used to investigate the effect of farm management and environmental risk factors on F. hepatica exposure. Higher rainfall, grazing boggy pasture, presence of beef cattle on farm, access to a stream or pond and smaller herd size were associated with an increased risk of exposure. Univariable regression was used to look for associations between fluke exposure and production-related variables including milk yield, composition, somatic cell count and calving index. Although causation cannot be assumed, a significant (p<0.001) negative association was seen between F. hepatica exposure and estimated milk yield at the herd level, representing a 15% decrease in yield for an increase in F. hepatica exposure from the 25th to the 75th percentile. This remained significant when fertility, farm management and environmental factors were controlled for. No associations were found between F. hepatica exposure and any of the other production, disease or fertility variables.
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Affiliation(s)
- Alison Howell
- Department of Infection Biology, Institute of Infection and Global Health, University of Liverpool, Liverpool, L69 7ZJ, UK; School of Veterinary Science, University of Liverpool, Leahurst, Chester High Road, Neston, CH64 7TE, UK.
| | - Matthew Baylis
- NIHR Health protection Research Unit in Emerging and Zoonotic Infections, Institute of Infection and Global Health, University of Liverpool, L69 7BE, UK; Department of Epidemiology and Population Health, Institute of Infection and Global Health, Leahurst, Chester High Road, Neston, CH64 7TE, UK
| | - Rob Smith
- School of Veterinary Science, University of Liverpool, Leahurst, Chester High Road, Neston, CH64 7TE, UK
| | - Gina Pinchbeck
- Department of Epidemiology and Population Health, Institute of Infection and Global Health, Leahurst, Chester High Road, Neston, CH64 7TE, UK; School of Veterinary Science, University of Liverpool, Leahurst, Chester High Road, Neston, CH64 7TE, UK
| | - Diana Williams
- Department of Infection Biology, Institute of Infection and Global Health, University of Liverpool, Liverpool, L69 7ZJ, UK; School of Veterinary Science, University of Liverpool, Leahurst, Chester High Road, Neston, CH64 7TE, UK
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33
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Olah S, van Wyk JA, Wall R, Morgan ER. FAMACHA©: A potential tool for targeted selective treatment of chronic fasciolosis in sheep. Vet Parasitol 2015. [PMID: 26223154 DOI: 10.1016/j.vetpar.2015.07.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
The liver fluke Fasciola hepatica causes considerable damage to the health, welfare and productivity of ruminants in temperate areas, and its control is challenged by anthelmintic resistance. Targeted selective treatment (TST) is an increasingly established strategy for preserving anthelmintic efficacy in grazing livestock, yet no practical indicators are available to target individuals for treatment against fluke infection. This paper evaluates the FAMACHA(©) system, a colour chart for the non-invasive detection of anaemia in small ruminants, for this purpose. FAMACHA(©) scores were collected from 288 sheep prior to slaughter during the winter period, when fluke infections were largely mature, and condemned livers were recovered and adult flukes extracted. Average FAMACHA(©) score was significantly higher (=paler conjunctivae) in animals whose livers were condemned (3.6, n=62) than in those whose livers were not condemned (2.1). The number of adult flukes recovered ranged from 2 to 485, and was positively correlated with FAMACHA(©) score (r(2)=0.54, p<0.001). Packed cell volume was correlated negatively with both FAMACHA(©) score (n=240, r=0.23, p<0.001) and fluke number (r=0.24, p<0.001). Nematode faecal egg count (FEC) did not correlate with FAMACHA(©) score, and selective treatment of individual sheep with FAMACHA(©) scores above 2 or 3 would have preserved between 27 and 100% of nematodes in refugia on the basis of FEC, depending on group and the threshold used for treatment. FAMACHA(©) holds promise as a tool for selective treatment of sheep against adult F. hepatica, in support of refugia-based control of fluke and nematode infections, and further field evaluation is warranted.
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Affiliation(s)
- Sophie Olah
- University of Bristol, School of Biological Sciences and School of Veterinary Science, Bristol Life Sciences Building, 24, Tyndall Avenue, Bristol BS8 1TQ, United Kingdom.
| | - Jan A van Wyk
- University of Pretoria, Faculty of Veterinary Science, Private Bag X20, Hatfield 0028, South Africa.
| | - Richard Wall
- University of Bristol, School of Biological Sciences and School of Veterinary Science, Bristol Life Sciences Building, 24, Tyndall Avenue, Bristol BS8 1TQ, United Kingdom.
| | - Eric R Morgan
- University of Bristol, School of Biological Sciences and School of Veterinary Science, Bristol Life Sciences Building, 24, Tyndall Avenue, Bristol BS8 1TQ, United Kingdom.
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Fox NJ, Marion G, Davidson RS, White PCL, Hutchings MR. Climate-driven tipping-points could lead to sudden, high-intensity parasite outbreaks. ROYAL SOCIETY OPEN SCIENCE 2015; 2:140296. [PMID: 26064647 PMCID: PMC4453250 DOI: 10.1098/rsos.140296] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2014] [Accepted: 04/23/2015] [Indexed: 05/27/2023]
Abstract
Parasitic nematodes represent one of the most pervasive and significant challenges to grazing livestock, and their intensity and distribution are strongly influenced by climate. Parasite levels and species composition have already shifted under climate change, with nematode parasite intensity frequently low in newly colonized areas, but sudden large-scale outbreaks are becoming increasingly common. These outbreaks compromise both food security and animal welfare, yet there is a paucity of predictions on how climate change will influence livestock parasites. This study aims to assess how climate change can affect parasite risk. Using a process-based approach, we determine how changes in temperature-sensitive elements of outbreaks influence parasite dynamics, to explore the potential for climate change to influence livestock helminth infections. We show that changes in temperate-sensitive parameters can result in nonlinear responses in outbreak dynamics, leading to distinct 'tipping-points' in nematode parasite burdens. Through applying two mechanistic models, of varying complexity, our approach demonstrates that these nonlinear responses are robust to the inclusion of a number of realistic processes that are present in livestock systems. Our study demonstrates that small changes in climatic conditions around critical thresholds may result in dramatic changes in parasite burdens.
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Affiliation(s)
- Naomi J. Fox
- Disease Systems Team, SRUC, King's Building, West Mains Road, Edinburgh EH9 3JG, UK
- Biomathematics and Statistics Scotland, King's Buildings, West Mains Road, Edinburgh EH9 3JZ, UK
- Department of Environment, University of York, Heslington, York YO10 5DD, UK
| | - Glenn Marion
- Biomathematics and Statistics Scotland, King's Buildings, West Mains Road, Edinburgh EH9 3JZ, UK
| | - Ross S. Davidson
- Disease Systems Team, SRUC, King's Building, West Mains Road, Edinburgh EH9 3JG, UK
| | - Piran C. L. White
- Department of Environment, University of York, Heslington, York YO10 5DD, UK
| | - Michael R. Hutchings
- Disease Systems Team, SRUC, King's Building, West Mains Road, Edinburgh EH9 3JG, UK
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Olsen A, Frankena K, Bødker R, Toft N, Thamsborg SM, Enemark HL, Halasa T. Prevalence, risk factors and spatial analysis of liver fluke infections in Danish cattle herds. Parasit Vectors 2015; 8:160. [PMID: 25888827 PMCID: PMC4374337 DOI: 10.1186/s13071-015-0773-x] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Accepted: 02/24/2015] [Indexed: 11/10/2022] Open
Abstract
Background Fasciola hepatica, a trematode parasite (liver fluke), infects a wide range of host species causing fasciolosis. The disease is prevalent world-wide and causes considerable economic losses to the livestock industry. Fasciolosis is regarded as an emerging food-borne zoonosis. To promote awareness among farmers and to implement strategies to control the infection, this study examined the prevalence, spatial distribution and risk factors for F. hepatica infection in Danish cattle herds. Methods A retrospective population based study was performed using meat inspection data of approximately 1.5 million cattle slaughtered in the period 2011 to 2013. Annual cumulative prevalence of recorded liver fluke findings was calculated for each year. Global and local spatial cluster analysis was used to identify and map spatial patterns of F. hepatica positive and negative herds to explore environmental indicators of infection. Herd level, trade and environmental risk factors were evaluated for association with infection using logistic regression. Herd infection status as predicted from the final risk factor model was compared with the observed status using heat maps to assess how well the model fitted the observed spatial pattern. Results During the investigated period (2011–2013), an increase in annual herd prevalence was noted (2011–25.6%; 2012–28.4%; 2013–29.3%). The spatial analysis suggested significant clustering of positive and negative herds. Presence of streams, wetlands and pastures on farms showed a significant association with the presence of infection in cattle herds. Buying animals from positive herds was a risk factor on conventional farms. Additionally, risk of being infected with F. hepatica was higher in non-dairy herds of medium size (≥30 and < 100) when compared to dairy and large (≥100) cattle herds. The observed spatial pattern could be reproduced by predictions of the risk factor model. Conclusions This study showed an increase in annual herd level prevalence (2011 to 2013) indicating that an increasing proportion of herds are infected with F. hepatica infection every year in Denmark. Fasciolosis was found to be associated with both herd and environmental factors where the infection was influenced by local factors that clustered geographically.
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Affiliation(s)
- Abbey Olsen
- Quantitative Veterinary Epidemiology group, Wageningen University, Wageningen, The Netherlands.
| | - Klaas Frankena
- Quantitative Veterinary Epidemiology group, Wageningen University, Wageningen, The Netherlands.
| | - Rene' Bødker
- Section for Epidemiology, National Veterinary Institute, Technical University of Denmark, Frederiksberg C, Denmark.
| | - Nils Toft
- Section for Epidemiology, National Veterinary Institute, Technical University of Denmark, Frederiksberg C, Denmark.
| | - Stig M Thamsborg
- Veterinary Parasitology Research Group, Department of Veterinary Disease Biology, University of Copenhagen, Frederiksberg C, Denmark.
| | - Heidi L Enemark
- Section for Bacteriology, Pathology and Parasitology, National Veterinary Institute, Technical University of Denmark, Frederiksberg C, Denmark.
| | - Tariq Halasa
- Section for Epidemiology, National Veterinary Institute, Technical University of Denmark, Frederiksberg C, Denmark.
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Molina-Hernández V, Mulcahy G, Pérez J, Martínez-Moreno Á, Donnelly S, O'Neill SM, Dalton JP, Cwiklinski K. Fasciola hepatica vaccine: we may not be there yet but we're on the right road. Vet Parasitol 2015; 208:101-11. [PMID: 25657086 PMCID: PMC4366043 DOI: 10.1016/j.vetpar.2015.01.004] [Citation(s) in RCA: 121] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Major advances have been made in identifying potential vaccine molecules for the control of fasciolosis in livestock but we have yet to reach the level of efficacy required for commercialisation. The pathogenesis of fasciolosis is associated with liver damage that is inflicted by migrating and feeding immature flukes as well as host inflammatory immune responses to parasite-secreted molecules and tissue damage alarm signals. Immune suppression/modulation by the parasites prevents the development of protective immune responses as evidenced by the lack of immunity observed in naturally and experimentally infected animals. In our opinion, future efforts need to focus on understanding how parasites invade and penetrate the tissues of their hosts and how they potentiate and control the ensuing immune responses, particularly in the first days of infection. Emerging 'omics' data employed in an unbiased approach are helping us understand liver fluke biology and, in parallel with new immunological data, to identify molecules that are essential to parasite development and accessible to vaccine-induced immune responses.
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Affiliation(s)
| | - Grace Mulcahy
- Veterinary Science Centre, University College Dublin, Belfield, Dublin, Ireland
| | - Jose Pérez
- School of Veterinary Medicine, University of Cordoba, Córdoba, Spain
| | | | - Sheila Donnelly
- The i3 Institute & School of Medical and Molecular Biosciences, University of Technology, Sydney, Australia
| | | | - John P Dalton
- School of Biological Sciences, Queen's University Belfast, Belfast, UK
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Bennema SC, Scholte RGC, Molento MB, Medeiros C, Carvalho ODS. Fasciola hepatica in bovines in Brazil: data availability and spatial distribution. Rev Inst Med Trop Sao Paulo 2014; 56:35-41. [PMID: 24553606 PMCID: PMC4085838 DOI: 10.1590/s0036-46652014000100005] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Accepted: 04/23/2013] [Indexed: 11/22/2022] Open
Abstract
Fasciolosis is a disease of importance for both veterinary and public
health. For the first time, georeferenced prevalence data of Fasciola
hepatica in bovines were collected and mapped for the Brazilian territory
and data availability was discussed. Bovine fasciolosis in Brazil is monitored on a
Federal, State and Municipal level, and to improve monitoring it is essential to
combine the data collected on these three levels into one dataset. Data were
collected for 1032 municipalities where livers were condemned by the Federal
Inspection Service (MAPA/SIF) because of the presence of F.
hepatica. The information was distributed over 11 states: Espírito Santo,
Goiás, Minas Gerais, Mato Grosso do Sul, Mato Grosso, Pará, Paraná, Rio de Janeiro,
Rio Grande do Sul, Santa Catarina and São Paulo. The highest prevalence of
fasciolosis was observed in the southern states, with disease clusters along the
coast of Paraná and Santa Catarina and in Rio Grande do Sul. Also, temporal variation
of the prevalence was observed. The observed prevalence and the kriged prevalence
maps presented in this paper can assist both animal and human health workers in
estimating the risk of infection in their state or municipality.
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Affiliation(s)
- Sita C Bennema
- Laboratório de Helmintologia e Malacologia Médica, Centro de Pesquisas René Rachou, Fiocruz, 30190-002Belo HorizonteMinas Gerais, Brazil, Laboratório de Helmintologia e Malacologia Médica, Centro de Pesquisas René Rachou, Fiocruz, Av. Augusto Lima 1715, Barro Preto, 30190-002 Belo Horizonte, Minas Gerais, Brazil
| | - Ronaldo Guilherme Carvalho Scholte
- Laboratório de Helmintologia e Malacologia Médica, Centro de Pesquisas René Rachou, Fiocruz, 30190-002Belo HorizonteMinas Gerais, Brazil, Laboratório de Helmintologia e Malacologia Médica, Centro de Pesquisas René Rachou, Fiocruz, Av. Augusto Lima 1715, Barro Preto, 30190-002 Belo Horizonte, Minas Gerais, Brazil
| | - Marcelo Beltrão Molento
- Laboratório de Doenças Parasitárias, Setor de Ciências Agrárias, Universidade Federal do Paraná, 80035-050CuritibaParaná, Brazil, Laboratório de Doenças Parasitárias, Setor de Ciências Agrárias, Universidade Federal do Paraná, Rua dos Funcionários 1540, Cabral, 80035-050 Curitiba, Paraná, Brazil
| | - Camilla Medeiros
- Laboratório de Helmintologia e Malacologia Médica, Centro de Pesquisas René Rachou, Fiocruz, 30190-002Belo HorizonteMinas Gerais, Brazil, Laboratório de Helmintologia e Malacologia Médica, Centro de Pesquisas René Rachou, Fiocruz, Av. Augusto Lima 1715, Barro Preto, 30190-002 Belo Horizonte, Minas Gerais, Brazil
| | - Omar Dos Santos Carvalho
- Laboratório de Helmintologia e Malacologia Médica, Centro de Pesquisas René Rachou, Fiocruz, 30190-002Belo HorizonteMinas Gerais, Brazil, Laboratório de Helmintologia e Malacologia Médica, Centro de Pesquisas René Rachou, Fiocruz, Av. Augusto Lima 1715, Barro Preto, 30190-002 Belo Horizonte, Minas Gerais, Brazil
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Recent advances in the diagnosis, impact on production and prediction of Fasciola hepatica in cattle. Parasitology 2013; 141:326-35. [PMID: 24229764 DOI: 10.1017/s0031182013001662] [Citation(s) in RCA: 106] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Fasciola hepatica is a pathogenic trematode parasite of ruminants with a global distribution. Here, we briefly review the current epidemiology of bovine fasciolosis in Europe and discuss the progress made over the last decade in the diagnosis, impact on production and prediction of F. hepatica in cattle. Advances in diagnosis have led to significantly improved coprological and serological methods to detect presence of infection. Diagnostic test results have been correlated with intensity of infection and associated production losses, unravelling the impact on carcass weight and milk yield in modern cattle production systems. The economic impact of fasciolosis may, however, go beyond the direct impacts on production as evidence shows that F. hepatica can modulate the immune response to some co-infections. Control of bovine fasciolosis remains hampered by the limitations of the currently available flukicidal drugs: few drugs are available to treat dairy cows, many have low efficacies against juvenile stages of F. hepatica and there is evidence for the development of drug resistance. This makes research into the prediction of risk periods, and thus the optimum application of available drugs more pertinent. In this field, the recent research focus has been on understanding spatial risk and delivering region-specific spatial distribution maps. Further advances in epidemiological and economic research on bovine fasciolosis are expected to deliver farm-specific economic assessments of disease impact, to leverage non-chemotherapeutic management options and to enhance a more targeted use of anthelmintics.
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Logue DN, Mayne CS. Welfare-positive management and nutrition for the dairy herd: a European perspective. Vet J 2013; 199:31-8. [PMID: 24360757 DOI: 10.1016/j.tvjl.2013.10.027] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2012] [Revised: 09/22/2013] [Accepted: 10/22/2013] [Indexed: 12/28/2022]
Abstract
As European dairy farms become larger and diverge between grass-based and fully housed systems, interest in the welfare of the dairy cow and related environmental issues by consumers and legislators is increasing. These pressures mean that good nutrition and management, which underpin much dairy cow welfare, is critical. Despite considerable research into the management and nutrition of the dairy cow from calf to adulthood there is much on-farm variability in its application. While the incidences of many endemic diseases are reduced most are still significant, for example lameness. In addition, trade and climate change are bringing a more diverse range of pathogens, parasites and pests into Northern Europe. Housing aspects are limited in application by economics and in most cases still do not match grazing for welfare in temperate climates. Genomic technologies offer increased opportunities to breed for 'robustness' but like 'precision animal management systems' have still to be fully exploited.
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Affiliation(s)
- David N Logue
- Large Animal Division, School of Veterinary Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Bearsden Road, Glasgow G61 1QH, UK.
| | - C Sinclair Mayne
- Agri-Food & Biosciences Institute, 18a NewForge Lane, Belfast BT9 5PX, UK
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Sekiya M, Zintl A, Doherty ML. Bulk milk ELISA and the diagnosis of parasite infections in dairy herds: a review. Ir Vet J 2013; 66:14. [PMID: 23883526 PMCID: PMC3733751 DOI: 10.1186/2046-0481-66-14] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2013] [Accepted: 06/27/2013] [Indexed: 11/10/2022] Open
Abstract
The bulk milk enzyme-linked immune sorbent assay (ELISA) is a rapid and inexpensive method of assessing herd exposure to pathogens that is increasingly being used for the diagnosis of parasite infections in dairy herds. In this paper, with the dairy herd health veterinarian in mind, we review the principles of the assay and the recent literature on the potential role of bulk milk ELISA for the diagnosis of ostertagiosis, fasciolosis, parasitic bronchitis due to cattle lung worm and neosporosis. It is generally accepted that assay results reflect exposure to the parasite rather than the presence of active infection. Bulk milk ELISA can be a useful tool for the veterinary practitioner as a component of a herd health monitoring programme or in the context of a herd health investigation. It can also play a role in regional or national surveillance programmes. However, the results need to be interpreted within the context of the herd-specific health management, the milk production pattern and the parasite life cycle.
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Affiliation(s)
- Mary Sekiya
- UCD School of Veterinary Medicine, University College Dublin, Belfield, Dublin 4, Ireland.
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41
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Identification of the rumen fluke, Calicophoron daubneyi, in GB livestock: possible implications for liver fluke diagnosis. Vet Parasitol 2013; 195:65-71. [PMID: 23411375 DOI: 10.1016/j.vetpar.2013.01.014] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2012] [Revised: 01/09/2013] [Accepted: 01/13/2013] [Indexed: 11/23/2022]
Abstract
The liver fluke, Fasciola hepatica, is common in many parts of Great Britain. To detect liver fluke infection and to assess whether fasciolicide treatment has been successful, the faecal egg count (FEC) and faecal egg count reduction test (FECRT) are widely used. Rumen fluke is also increasingly reported from Great Britain, but its species identity is yet to be determined. Liver fluke and rumen fluke eggs are morphologically similar, which may lead to erroneous diagnoses of liver fluke infection or treatment failure. As an alternative to FEC, a coproantigen ELISA (cELISA) can be used. The potential for this test to cross-react with rumen fluke species from Great Britain has not been evaluated. Rumen fluke specimens from cattle and sheep in Scotland were identified to species level using DNA sequencing of the ITS-2 region. Subsequently, rumen and liver fluke obtained from naturally co-infected sheep were subjected to immunohistochemistry using antibodies from a commercially available cELISA kit for F. hepatica. Finally, faecal samples from naturally co-infected sheep flocks were examined by FEC and cELISA. Rumen fluke from imported and home-bred cattle and sheep in Scotland belonged to the species Calicophoron daubneyi, rather than Paramphistomum cervi, the species presumed to be most common in Great Britain. Intense staining of the gastrodermis was observed in F. hepatica but cross-reactivity with C. daubneyi was not seen. Faecal samples that contained rumen fluke eggs but not liver fluke eggs were all negative by cELISA. We conclude that C. daubneyi is the most common rumen fluke of domestic ruminants in Scotland and that cELISA reduction testing may be a valuable alternative to FECRT in herds or flocks that are co-infected with liver and rumen fluke.
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Carneiro MB, Alves DP, Donatele DM, Pereira Junior ODS, Martins IVF. Fasciola hepatica em ovinos, caprinos e bubalinos em municípios do sul do Espírito Santo. ARQUIVOS DO INSTITUTO BIOLÓGICO 2013. [DOI: 10.1590/s1808-16572013000400011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
O objetivo deste trabalho foi registrar a presença de Fasciola hepatica em ovinos, caprinos e bubalinos em dez municípios do sul do Espírito Santo e relacionar fatores determinantes da doença na região. Um total de 34 propriedades de ovinos, caprinos e bubalinos foi visitado coletando-se amostras fecais dessas espécies para procedimento da técnica de sedimentação. Um total de 58 (13,68%) amostras de ovinos, 76 (21,78%) amostras de caprinos e 10 (23,81%) amostras de bubalinos foram positivas para ovos de F. hepatica. Todos os moluscos coletados foram identificados como pertencentes à espécie Lymnaea columella. Notou-se que os municípios da região sul do Espírito Santo apresentam altas taxas de F. hepatica em ovinos, caprinos e bubalinos, tornando essa região um grande foco de dispersão da parasitose, e que a ocorrência de casos anteriores de fasciolose nas propriedades ficou caracterizada como fator de risco epidemiológico para a doença.
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Affiliation(s)
- Phyllis Kanki
- , Department of Immunology and Infectious, Harvard School of Public Health, Huntington Avenue 651, Boston, 02115 Massachusetts USA
| | - Darrell Jay Grimes
- , Department of Coastal Sciences, The University of Southern Mississippi, East Beach Drive 703, Ocean Springs, 39564 Mississippi USA
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Daniel R, van Dijk J, Jenkins T, Akca A, Mearns R, Williams DJL. Composite faecal egg count reduction test to detect resistance to triclabendazole in Fasciola hepatica. Vet Rec 2012; 171:153, 1-5. [DOI: 10.1136/vr.100588] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- R. Daniel
- Animal Health and Veterinary Laboratories Agency (AHVLA) Carmarthen; Job's Well Road, Johnstown Carmarthen SA31 3EZ UK
| | - J. van Dijk
- Department of Epidemiology and Population Health; Institute of Infection and Global Health, Leahurst; Chester High Road Neston Cheshire CH64 7TE UK
| | - T. Jenkins
- Department of Parasitology; Faculty of Veterinary Medicine; University of Kafkas; Kars 36040 Turkey
| | - A. Akca
- Animal Health and Veterinary Laboratories Agency (AHVLA); Penrith Investigation Centre and Laboratory; Calthwaite Penrith Cumbria CA11 9RR UK
| | - R. Mearns
- Veterinary Parasitology; Institute of Infection and Global Health; University of Liverpool; Pembroke Place Liverpool L69 7ZJ UK
| | - D. J. L. Williams
- Animal Health and Veterinary Laboratories Agency (AHVLA) Carmarthen; Job's Well Road, Johnstown Carmarthen SA31 3EZ UK
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Geurden T, Bartram D, Van Brussel L, Bo L, Scott-Baird E, Rugg D. Evaluation of the comparative efficacy of a moxidectin plus triclabendazole pour-on solution against adult and immature liver fluke, Fasciola hepatica, in cattle. Vet Parasitol 2012; 189:227-32. [PMID: 22579500 DOI: 10.1016/j.vetpar.2012.04.019] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2012] [Revised: 04/16/2012] [Accepted: 04/16/2012] [Indexed: 11/16/2022]
Abstract
The objective of this study was to evaluate the efficacy of a pour-on solution containing moxidectin plus triclabendazole (MOX plus TCBZ) against immature and adult stages of the liver fluke in cattle and compare the efficacy with other commercially available preparations. To this end, 104 male Holstein-Friesian calves aged between 3 and 4 months, were randomly allocated to 13 groups of eight animals each, and infected with approximately 500 Fasciola hepatica metacercariae. One group remained untreated, four groups were treated with MOX plus TCBZ at a dose rate of 0.1 mL/kg, four other groups were treated with ivermectin (IVM) plus clorsulon injectable at a dose rate of 0.02 mL/kg, and the remaining four groups were treated with IVM plus closantel pour-on at a dose rate of 0.1 mL/kg. Each treatment was applied to one of the groups at 4 weeks, 6 weeks, 8 weeks and 12 weeks after the experimental infection. At necropsy (99-102 days after infection), all untreated animals were infected with a minimum of 30 flukes. The MOX plus TCBZ treated animals had significantly (P<0.0001) lower fluke counts compared to the untreated control animals at all time points after treatment. Efficacy against 8-week old and adult flukes was >99.5%. For 6-week old immature fluke, the efficacy was 98.0% and for 4-week old immature fluke the efficacy was 90.9%. The IVM plus closantel pour-on treated animals had significantly lower fluke counts compared to the untreated control animals for adult and 8-week old flukes (P<0.0001), and for 6-week old flukes (P=0.002). The efficacy was 26.8%, 68.2%, 90.6% and 99.3% against 4-week, 6-week and 8-week old immature flukes, and adult flukes respectively. The IVM plus clorsulon treated animals had significantly lower fluke counts compared to the untreated control animals for adult (P<0.0001) and 8-week old (P<0.05) flukes. The efficacy was 29.7%, 43.4%, 53.2% and 99.2% against 4-week, 6-week and 8-week old immature flukes, and adult flukes respectively. For treatments at 4, 6 and 8 weeks after infection, the fluke counts were significantly (P<0.0001) lower for the MOX plus TCBZ treatment than for IVM plus closantel or IVM plus clorsulon. The results confirm the high efficacy (>90%) of the MOX plus TCBZ pour-on combination against 4-week old to adult liver fluke in cattle. The IVM plus closantel pour-on combination was effective (>90%) against 8-week old and adult flukes, but had low efficacy against 4- and 6-week old fluke. The IVM plus clorsulon injectable combination was effective (>90%) against adult fluke only.
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Affiliation(s)
- Thomas Geurden
- Pfizer Animal Health, Veterinary Medicine Research and Development, Hoge Wei 10, 1930 Zaventem, Belgium.
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Fox NJ, Marion G, Davidson RS, White PCL, Hutchings MR. Livestock Helminths in a Changing Climate: Approaches and Restrictions to Meaningful Predictions. Animals (Basel) 2012; 2:93-107. [PMID: 26486780 PMCID: PMC4494270 DOI: 10.3390/ani2010093] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2012] [Revised: 02/27/2012] [Accepted: 03/02/2012] [Indexed: 11/17/2022] Open
Abstract
Climate change is a driving force for livestock parasite risk. This is especially true for helminths including the nematodes Haemonchus contortus, Teladorsagia circumcincta, Nematodirus battus, and the trematode Fasciola hepatica, since survival and development of free-living stages is chiefly affected by temperature and moisture. The paucity of long term predictions of helminth risk under climate change has driven us to explore optimal modelling approaches and identify current bottlenecks to generating meaningful predictions. We classify approaches as correlative or mechanistic, exploring their strengths and limitations. Climate is one aspect of a complex system and, at the farm level, husbandry has a dominant influence on helminth transmission. Continuing environmental change will necessitate the adoption of mitigation and adaptation strategies in husbandry. Long term predictive models need to have the architecture to incorporate these changes. Ultimately, an optimal modelling approach is likely to combine mechanistic processes and physiological thresholds with correlative bioclimatic modelling, incorporating changes in livestock husbandry and disease control. Irrespective of approach, the principal limitation to parasite predictions is the availability of active surveillance data and empirical data on physiological responses to climate variables. By combining improved empirical data and refined models with a broad view of the livestock system, robust projections of helminth risk can be developed.
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Affiliation(s)
- Naomi J Fox
- SAC, West Mains Road, Edinburgh, EH9 3JG, UK.
- Environment Department, University of York, Heslington, York, YO10 5DD, UK.
- Biomathematics and Statistics Scotland, Kings Buildings, Edinburgh, EH9 3JZ, UK.
| | - Glenn Marion
- Biomathematics and Statistics Scotland, Kings Buildings, Edinburgh, EH9 3JZ, UK.
| | | | - Piran C L White
- Environment Department, University of York, Heslington, York, YO10 5DD, UK.
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Gordon DK, Zadoks RN, Stevenson H, Sargison ND, Skuce PJ. On farm evaluation of the coproantigen ELISA and coproantigen reduction test in Scottish sheep naturally infected with Fasciola hepatica. Vet Parasitol 2012; 187:436-44. [PMID: 22421492 DOI: 10.1016/j.vetpar.2012.02.009] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2011] [Revised: 01/20/2012] [Accepted: 02/15/2012] [Indexed: 11/28/2022]
Abstract
The liver fluke, Fasciola hepatica, is a cause of significant economic losses in sheep farming. Lack of convenient and sensitive diagnostic tests in the live animal hampers the ability to monitor infection status and treatment efficacy. Use of a coproantigen ELISA and coproantigen reduction test, based on this ELISA, may address these issues but has, to date, only been evaluated in experimental challenge studies. We evaluated the coproantigen ELISA under working farm conditions in Scotland to assess its usefulness as a diagnostic test for liver fluke infection and as a diagnostic test to help determine the efficacy of flukicide treatment in sheep. First, liver fluke infection status was monitored longitudinally in a group of lambs, using monthly blood samples for biochemical assays and serum antibody ELISA and using monthly faecal samples for faecal egg count (FEC) and coproantigen ELISA. The average serum antibody ELISA titre became positive in September, two months ahead of faecal indicators of fluke infection. In contrast to results from experimental challenge studies, FEC and coproantigen ELISA became positive at the same time point. Secondly, treatment efficacy was measured in 100 ewes, from two farms, after treatment with triclabendazole (TCBZ) or closantel. Group level estimates of treatment efficacy were similar between faecal egg count reduction testing and coproantigen reduction testing at 7, 14 and 21 days post treatment. For individual animals, some inconsistencies between tests were observed. TCBZ treatment failure was noted on both farms, despite accurate weighing of animals and dosing of treatment products. We conclude that (1) coproantigen ELISA is a more convenient test than faecal egg counts and holds promise as a diagnostic tool for natural fluke infections in sheep but further evaluation of interpretation criteria may be needed; (2) the coproantigen ELISA has performed differently in the field compared with experimental challenge studies in sheep and (3) TCBZ-resistant fluke were present on both farms.
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Affiliation(s)
- D K Gordon
- Moredun Research Institute, Pentlands Science Park, Penicuik, Midlothian EH26 0PZ, United Kingdom.
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48
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Climate Change and Human Health: A One Health Approach. Curr Top Microbiol Immunol 2012. [DOI: 10.1007/978-3-662-45791-7_274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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49
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Baylis M, Risley C. Climate Change Effects on Infectious Diseases. Infect Dis (Lond) 2012. [DOI: 10.1007/978-1-0716-2463-0_524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/10/2023] Open
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50
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Ellis KA, Jackson A, Bexiga R, Matthews J, McGoldrick J, Gilleard J, Forbes AB. Use of diagnostic markers to monitor fasciolosis and gastrointestinal nematodes on an organic dairy farm. Vet Rec 2011; 169:524. [PMID: 21908552 DOI: 10.1136/vr.d5021] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
A 12-month study was conducted to assess and monitor gastrointestinal tract nematodes and liver fluke in cohorts of cattle on a Scottish organic dairy farm. Various diagnostic markers for helminth parasites of cattle from different age groups were assessed monthly from April 2007 to March 2008. First season grazing stock were subjected to significant challenge from Ostertagia ostertagi nematodes as reflected in serum pepsinogen concentrations, which rose markedly in the second half of the grazing season. In addition, plasma albumin concentrations decreased and faecal egg counts (FEC) increased moderately, indicating exposure to both O ostertagi and probably Cooperia oncophora. Second season grazing animals had a peak FEC early in the grazing period, suggestive of a potential carry-over of Ostertagia species infection ('Type 2') during housing. All classes of cattle showed evidence of fluke (Fasciola hepatica) infection. Adult cow exposure to O ostertagi and fluke was estimated via the use of ELISA testing to detect antibodies to O ostertagi and F hepatica and the high levels detected suggested a significant exposure response. Despite low stocking densities and sympathetic grazing management, there was a significant challenge to all grazing stock from gastrointestinal nematodes and liver fluke.
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Affiliation(s)
- K A Ellis
- Scottish Centre for Production Animal Health and Food Safety, School of Veterinary Medicine, College of Veterinary and Life Sciences.
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