Fasciola hepatica in UK horses

In Vitro Effects of Vanadate Erbium/Silver Oxide (ErVO4/AgO) and Vanadate Iron/Silver Oxide (FeVO4/AgO) Nanoparticles on the Adult of Fasciola hepatica

Fascioliasis is a common hepatic parasitic disease that is caused by Fasciola, resulting in significant economic losses by reducing production and consigning viscera in animals. Currently, there is little research regarding the impact of chemical compounds on the ultrastructure and motility of adult F. hepatica. The present study aims to assess the effect of Vanadate erbium/silver oxide (ErVO4/AgO) and Vanadate iron/silver oxide (FeVO4/AgO) nanoparticles against liver fluke F. hepatica, in vitro assay. Fasciola hepatica adult worms were collected from the livers and gallbladders of sheep and goats centrality of Iran. One hundred fresh worms were incubated with each nanoparticle concentration of 4.5-6 mg/mL FeVO4/AgO and ErVO4/AgO (test, groups) in comparison to triclabendazole 5-20 µg/mL (positive control) and RPMI media culture (negative control) after 12 and 24 hours of treatment. To ensure the reliability of the data, the tests on the sample were performed twice. The effectiveness of these compounds was evaluated by examining parasite movement, reaction to vital stain and changes in the tegument through scanning electron microscopy (SEM) using Fisher statistical tests and logistic regression. Analysis of variance was performed to compare Kaplan-Meier and Cox groups and models to analyse parasite survival. In addition, the anthelmintic efficacy was measured as the mortality rate based on the number of live and dead worms. The mortality ratios show that the anthelmintic activities of the compounds highly relied on time and concentration, as time and concentration increased, increasing the mortality rate. Lethal concentration 50 (LC50) of FeVO4/AgO and ErVO4/AgO are 4, 4.7 and 5 mg/mL at 24 h, respectively. FeVO4/AgO showed more lethal effects on F. hepatica than on ErVO4/AgO and triclabendazole. SEM analysis of treated F. hepatica by both nanoparticles at a concentration of 6 mg/mL showed that the tegument surface of fasciola is swollen in some parts, the pores on the tegument surface are completely visible, the sensory papillae are lost, the tegument is severely damaged and the prominent network structure and its vesicles have completely disappeared. F. hepatica is more susceptible to the lethal effects of FeVO4/AgO and ErVO4/AgO nanoparticles. The effectiveness of these compounds depends on the concentration and time of the drug's effect, in such a way that the effectiveness increases with the increase in concentration and time.

Fasciola hepatica in donkeys from southern Texas, USA

Fasciola hepatica is a trematode parasite with a global distribution found in various mammalian hosts, most notably ruminants. It is associated with hepatic lesions including necrosis and inflammation, as well as can increase the risk of secondary bacterial infections. There is a lack of reports of fasciolosis in equids in North America. This report documents the pre- and postmortem findings of two cases of chronic fasciolosis in donkeys from southern Texas, United States. Grossly, left hepatic lobe atrophy and concurrent right lobe hypertrophy was observed. Histologic examination of the liver showed classic findings of intra-ductular trematode adults and eggs with biliary hyperplasia and fibrosis.

Prevalence of Bovine Fasciolosis, Financial Losses and Risk Factors Associated with the Disease in Lira and Gulu Districts, Northern Uganda

Bovine fasciolosis (BF) is a parasitic disease of cattle that causes significant economic impacts to cattle farmers. The physical loses include weight loss, drop in productivity, liver condemnation and mortalities. This study assessed the prevalence, financial losses and risk factors associated with the disease in Lira and Gulu Districts, northern Uganda. A cross-sectional study of 720 slaughter cattle from the abattoirs was conducted by macroscopic examination of the animals and carcasses during routine slaughter. In the farms, 120 rectal faecal samples were taken to a laboratory for Fasciola egg detection by simple microscopy, while risk factors were assessed by administering a questionnaire to farm owners. Prevalence of BF was highest (38%) within cattle in the age group of 1-3 years and lowest (18%) in those over 5 years. The overall BF prevalence was 48% and 26% by postmortem examination and coprology, respectively. The cattle body condition had a significant association (p < 0.01) with prevalence of BF, in which emaciated cattle were most affected (59%), while fat ones had the least prevalence (15%). The annual financial loss due to BF infection was USD 89,099. The major risk factors associated with the disease at the farm level were communal grazing in swampy areas (82%) and watering cattle in swamps (71%). Farms where the source of drinking water was swamp water had higher chances (p < 0.05) of their cattle having BF. An integrated approach using routine deworming programs, improvement of cattle management practices and control of snail intermediate hosts is recommended to effectively control the spread of BF.

Equine helminths: prevalence and associated risk factors in Gamo Gofa Zone, Ethiopia

IMPORTANCE

Equines are indispensable in reducing the huge burden on children and women and income generation. On the other hand, minimal attention is given to improving their health and welfare.

OBJECTIVE

This study examined the prevalence and associated risk factors of helminth parasites of equine in the Gamo Gofa Zone.

METHODS

A cross-sectional study was employed from June 2019 to March 2020. The study districts and Kebeles were selected purposively based on agroecology whereas selection of study households and animals were performed based on simple random sampling techniques. Identification of nematode, trematode parasite ova and larvae of D. arnfieldi were done by floatation, sedimentation, and Baermann techniques respectively. Descriptive statistics and logistic regression was applied to estimate the prevalence and association of risk factors with helminth parasites.

RESULTS

The overall helminth parasite prevalence in the study area was 90.4%, 425/470 (95% [CI], 87.16-92.9). The prevalence of Strongyle, Fasciola, O. equi, P. equorum, D. arnfieldi, and mixed parasite infections were 65.1%, 21.7%, 17.4%, 34%, 34%, and 58.1%, respectively. Infections from Fasciola species and D. arnfieldi infection were four ([AOR], 4.4; 95% CI, 2-9.4) and two times (AOR, 2; 95% CI, 1.1-3.6) respectively more likely occur in donkeys than in mules. The occurrence of Strongyle species in midland agroecology was two times (AOR, 2.6; 95% CI, 1.4-4.7) more likely than lowland agroecology.

CONCLUSIONS AND RELEVANCE

The present study identified diverse species of equine helminth parasites that necessitate urgent disease control and prevention measures.

BEVA primary care clinical guidelines: Equine parasite control

BACKGROUND

There is a lack of consensus on how best to balance our need to minimise the risk of parasite-associated disease in the individual horse, with the need to limit the use of anthelmintics in the population to preserve their efficacy through delaying further development of resistance.

OBJECTIVES

To develop evidence-based guidelines utilising a modified GRADE framework.

METHODS

A panel of veterinary scientists with relevant expertise and experience was convened. Relevant research questions were identified and developed with associated search terms being defined. Evidence in the veterinary literature was evaluated using the GRADE evidence-to-decision framework. Literature searches were performed utilising CAB abstracts and PubMed. Where there was insufficient evidence to answer the research question the panel developed practical guidance based on their collective knowledge and experience.

RESULTS

Search results are presented, and recommendation or practical guidance were made in response to 37 clinically relevant questions relating to the use of anthelmintics in horses.

MAIN LIMITATIONS

There was insufficient evidence to answer many of the questions with any degree of certainty and practical guidance frequently had to be based upon extrapolation of relevant information and the panel members' collective experience and opinions.

CONCLUSIONS

Equine parasite control practices and current recommendations have a weak evidence base. These guidelines highlight changes in equine parasite control that should be considered to reduce the threat of parasite-associated disease and delay the development of further anthelmintic resistance.

Fasciola hepatica Infection in Horses in Three Governorates in Northern Egypt: Prevalence and Risk Factors

Fasciola hepatica is a trematode parasite that affects wide range of mammalian hosts including horses. There are no epidemiological data on fasciolosis in Egyptian horses. Hence, the present study aimed to evaluate the seroprevalence of F. hepatica in horses using ELISA as well as assess the associated risk factors for fasciolosis infection. A total of 400 sera samples of horses from three Egyptian governorates were examined. The overall seroprevalence rate in horses was 13% and the disease was more prevalent in Qalubia (14.17%) and Gharbia (16.67%) which are located at Nile Delta. The likelihood of having F. hepatica seropositivity was higher in mixed-breed animals and stallions (OR = 3.97, 95%CI: 1.10-14.28 and OR = 2.07, 95%CI: 1.09-3.93, respectively), and in older horses more than 10 years (OR = 5.69, 95% CI: 1.98-16.36). Horses were more likely to be seropositive with F. hepatica when kept in outdoor housing (OR= 1.53, 95%CI: 0.78-3), during autumn (OR = 3.80, 95%CI: 1.17-12.32) and in the presence of snails (OR = 2.72, 95%CI: 1.34-5.52). Therefore, the obtained data contributes to the understanding of the epidemiology of Fasciola species, assess in establishment of management programmes to reduce disease and public health risks.

Prevalence and hepatic histopathological findings of fascioliasis in sheep slaughtered in Jeddah, Saudi Arabia

Hepatic fascioliasis is an important parasitic disease responsible for morbidity and mortality in many domestic ruminants, especially sheep, goats, and cattle, due to Fasciola (F.) hepatica and F. gigantica. This study aimed to determine the prevalence of fascioliasis in sheep slaughtered in Jeddah, Saudi Arabia, and to describe the morphological and histopathological changes in the liver. A total of 109,253 sheep slaughtered between July 2017 and July 2018 were screened to assess the prevalence of fascioliasis. The livers were grossly investigated for Fasciola infection and morphological changes. Tissue samples were collected for proper histopathological examinations. Livers of local and imported sheep represented infection rates of 0.67% and 2.12%, respectively, and the highest infection rate was in the spring season. Macroscopically, the affected liver showed hepatomegaly, thickened capsule and discoloration with necrosis, fibrosis, dilation of the bile duct, engorgement of the gallbladder and enlargement of the portal lymph nodes. Microscopic examination showed fibrotic thickening, calcification and hyperplasia of the bile ducts filled with debris, as well as massive hemorrhagic foci. Histopathological examinations of the infected liver showed a central vein region with disturbed parenchyma cells, focal lymphocytic infiltration, elongated endothelial cells, blood sinusoids that showed enlarged Kupffer cells, patches of lysed or necrotic hepatocytes, eosinophil infiltration, lymphocytes and proliferating fibroblast, thickening of hepatic artery and arteriolar walls. We concluded that fascioliasis among sheep slaughtered in Jeddah is not uncommon. The identified histopathological changes in the liver of infected sheep reflect tissue damage, which can lead to significant economic losses for the animals.

A Comparative Study of Fasciola Parasite Infection Rates in Local and Imported Sheep in Jeddah, Saudi Arabia

Fasciola hepatica and Fasciola gigantica are two trematodes (liver flukes) that cause water- and food-borne disease Fasciolosis. Many animals are involved in the life cycle of the Fasciola spp., such as sheep, cattle, and camels, and humans are the definitive host. This work investigated the prevalence of Fasciola among imported and local slaughtered sheep and the relation between infection rate and seasons of the year. A total of 720,290 local and imported sheep (251,701 and 468,489, respectively) were slaughtered in a Jeddah slaughterhouse (Western region of Saudi Arabia) over the periods of 2017-2018, 2018-2019, and 2019-2020. In the three years of inspection, the infection rate at slaughter was higher among imported than local sheep. In 2017-2018, both local and imported sheep had the highest level of infection in the spring and the lowest in the winter. However, in 2018-2019, the highest rate of infection for both was documented in the summer and the lowest in the winter. Lastly, in 2019-2020, the highest rate of infection for local sheep was observed in the summer of 2020 and the lowest rate of infection was observed in the spring of 2020. Among imported sheep, the highest rate of infection was in the summer and the lowest was in winter for both 2019 and 2020. To control this disease, there is the need to apply for successful integrated programs and practice adaptive management techniques.

High prevalence and risk factors of fascioliasis in cattle in Amazonas, Peru

Fascioliasis is a zoonotic disease caused by parasites of the genus Fasciola spp. which cause an important loss to the livestock industry. The objectives of this study were: to estimate the prevalence of fascioliasis in three provinces of Amazonas, to evaluate possible risk factors of infection in cattle and to genetically characterize the Fasciola haplotypes circulating in this area. According to the results the prevalence of fascioliasis in cattle was 90.13% (712/790). Odds ratio results showed a significant association between fascioliasis and the Brown Swiss breed (OR = 2.62; 95% CI: 1.57-4.35; p < 0.001), and with female cattle older than 30 months (OR = 1.71; 95% CI: 1.05-2.79; p < 0.031). According to the molecular genetic studies using the gene marker NAD1, six haplotypes of Fasciola hepatica were found in the 35 infected livers collected. The results obtained in this study are concerning due to the high prevalence presented and it reveals the necessity of a continuing monitoring because of the high risk of transmission to humans.

Evidence of population structuring following population genetic analyses of Fasciola hepatica from Argentina

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320 Argentinian Fasciola hepatica were genotyped using a panel of microsatellites.

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Overall there was high genotypic richness: 263 distinct genotypes were identified.

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Population structuring of F. hepatica was evident across Argentina.

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Within these sub-populations there is largely random mating.

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Transmission of clonemates occurs: clonal parasites accounted for 26.6% of all parasites.

Fasciola hepatica, the liver fluke, is a trematode parasite that causes disease of economic importance in livestock. As a zoonosis this parasite also poses a risk to human health in areas where it is endemic. Population genetic studies can reveal the mechanisms responsible for genetic structuring (non-panmixia) within parasite populations and provide valuable insights into population dynamics, which in turn enables theoretical predictions of evolutionary dynamics such as the evolution of drug resistance. Here we genotyped 320 F. hepatica collected from 14 definitive hosts from four provinces in Argentina. STRUCTURE analysis indicated three population clusters, and principal coordinate analysis confirmed this, showing population clustering across provinces. Similarly, pairwise F_ST values amongst all four provinces were significant, with standardised pairwise F_ST (F′_ST) ranging from 0.0754 to 0.6327. Therefore, population genetic structure was evident across these four provinces in Argentina. However, there was no evidence of deviation from Hardy–Weinberg equilibrium, so it appears that within these sub-populations there is largely random mating. We identified 263 unique genotypes, which gave a clonal diversity of 82%. Parasites with identical genotypes, clones, accounted for 26.6% of the parasites studied and were found in 12 of the 14 hosts studied, suggesting some clonemate transmission.

Parasitic diseases of equids in Iran (1931-2020): a literature review

Parasitic infections can cause many respiratory, digestive and other diseases and contribute to some performance conditions in equids. However, knowledge on the biodiversity of parasites of equids in Iran is still limited. The present review covers all the information about parasitic diseases of horses, donkeys, mules and wild asses in Iran published as articles in Iranian and international journals, dissertations and congress papers from 1931 to July 2020. Parasites so far described in Iranian equids include species of 9 genera of the Protozoa (Trypanosoma, Giardia, Eimeria, Klossiella, Cryptosporidium, Toxoplasma, Neospora, Theileria and Babesia), 50 helminth species from the digestive system (i.e., 2 trematodes, 3 cestodes and 37 nematodes) and from other organs (i.e., Schistosoma turkestanica, Echinococcus granulosus, Dictyocaulus arnfieldi, Parafilaria multipapillosa, Setaria equina and 3 Onchocerca spp.). Furthermore, 16 species of hard ticks, 3 mite species causing mange, 2 lice species, and larvae of 4 Gastrophilus species and Hippobosca equina have been reported from equids in Iran. Archeoparasitological findings in coprolites of equids include Fasciola hepatica, Oxyuris equi, Anoplocephala spp. and intestinal strongyles. Parasitic diseases are important issues in terms of animal welfare, economics and public health; however, parasites and parasitic diseases of equines have not received adequate attention compared with ruminants and camels in Iran. The present review highlights the knowledge gaps related to equines about the presence, species, genotypes and subtypes of Neospora hughesi, Sarcocystis spp., Trichinella spp., Cryptosporidium spp., Giardia duodenalis, Blastocystis and microsporidia. Identification of ticks vectoring pathogenic parasites, bacteria and viruses has received little attention, too. The efficacy of common horse wormers also needs to be evaluated systematically.

The prevalence and risk factors of liver fluke infection in Mexican horses, donkeys and mules in tropical and temperate regions

The objective of the present study was to determine the seroprevalence of Fasciola hepatica infection in horses, donkeys and mules from different climate regions in two states of Mexico. A total of 594 serum samples were analysed for immunoglobulin G (IgG) antibodies using enzyme-linked immunosorbent assay (ELISA), with excretory-secretory (E/S) products as the antigen. The diagnostic sensitivity and specificity of serum IgG ELISA were 100% and 97.2%, respectively. We collected data using a questionnaire. The overall prevalence of the parasite in equids between May 2018 and April 2019 was 13.1% (78 out of 594). The highest prevalence was found in mules (17.9%), followed by that in donkeys (13.9%) and horses (10.4%). In addition, the highest percentage of positive equines was detected in samples from the tropical climate (17.5%). The identification of risk factors was assessed by bivariate logistic regression analysis. Mules had 8.608 times higher risk for F. hepatica infections as compared with horses (odds ratio (OR) 8.608; 95% confidence interval (CI): 2.809-26.377), while the OR for 6-10-year-old equines was 93.375 compared with that of young equines (≤ 5 years old) (OR 93.375; 95% CI: 11.075-787.239). Likewise, tropical climate equines had 83.7% increased odds for fasciolosis (OR 1.83).

Equines as reservoirs of human fascioliasis: transmission capacity, epidemiology and pathogenicity in Fasciola hepatica-infected mules

Fascioliasis is a zoonotic disease caused by liver flukes transmitted by freshwater lymnaeid snails. Donkey and horse reservoir roles have been highlighted in human endemic areas. Liver fluke infection in mules has received very limited research. Their role in disease transmission, epidemiological importance and Fasciola hepatica pathogenicity are studied for the first time. Prevalence was 39.5% in 81 mules from Aconcagua, and 24.4% in 127 from Uspallata, in high-altitude areas of Mendoza province, Argentina. A mean amount of 101,242 eggs/mule/day is estimated. Lymnaeids from Uspallata proved to belong to ribosomal DNA internal transcribed spacer (ITS) markers ITS-1 and ITS-2 combined haplotype 3C of Galba truncatula. These lymnaeids were experimentally susceptible to infection by egg miracidia from mules. Infectivity, number of cercariae/snail and shedding period fit the enhanced F. hepatica/G. truncatula transmission pattern at very high altitude. This indicates that the mule is able to maintain the F. hepatica cycle independently. Individual burdens of 20 and 97 flukes were found. Mule infection susceptibility is intermediate between donkey and horse, although closer to the latter. Anatomo-pathology and histopathology indicate that massive infection may cause mule death. Haematological value decreases of red blood cells, haemoglobin, leucocytes and lymphocytes indicate anaemia and strong immunosuppression. Strongly increased biochemical marker values indicate liver function alterations. The mule probably played a role in the past exchanges with Chile and Bolivia through Mendoza province. Evidence suggests that mules could contribute to the spread of both F. hepatica and G. truncatula to human fascioliasis-endemic areas in these countries.