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Racicot M, Cardinal AM, Tremblay D, Vaillancourt JP. Technologies monitoring and improving biosecurity compliance in barn anterooms. Front Vet Sci 2022; 9:1005144. [PMID: 36406088 PMCID: PMC9673170 DOI: 10.3389/fvets.2022.1005144] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Accepted: 09/14/2022] [Indexed: 10/29/2023] Open
Abstract
People can act as mechanical vectors, and introduce and spread infectious diseases on farms. Preventive measures, such as changing boots and washing hands, need systematic implementation to manage this risk. Unfortunately, biosecurity compliance regarding biosecurity measures in barn anterooms has been shown to be generally low in all animal production systems. Indeed, the main challenge with biosecurity is maintaining compliance. The development of an effective on-farm biosecurity program requires several elements. These include farm and barn designs facilitating implementation of biosecurity measures; consistently communicating with all personnel and visitors informing them about threats and biosecurity; training programs for all farm personnel, explaining why biosecurity is effective in preventing infectious disease transmission, which measures are needed, and how to best implement them. All these components would be further optimized if automated monitoring systems were implemented with feedback mechanisms. Technologies are now available and are being adapted to the farm context to monitor biosecurity compliance. Two pilot projects using radio-frequency-identification-based (RFID) real-time continuous automated monitoring system quantifying hand sanitizing and boot compliance were conducted. The first one (MediHand Trace system) was a system designed to monitor and provide real-time feedback for handwashing in a hospital environment. It was functional for this task, although not sturdy enough for long-term use in a farm environment. The second system was a prototype designed for barns and with foot mats allowing the monitoring of footwear management as well as handwashing. These pilot studies have shown that real-time feedback helps improve compliance. However, the efficacy of the systems was very dependent on the physical set-up of the anteroom.
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Affiliation(s)
- Manon Racicot
- Department of Pathology and Microbiology, Faculty of Veterinary Medicine, Université de Montréal, Montreal, QC, Canada
| | - Anne-Marie Cardinal
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Université de Montréal, Montreal, QC, Canada
| | - Dominic Tremblay
- Institut de technologie Agroalimentaire du Québec, Programme de technologie des productions animales, St-Hyacinthe, QC, Canada
| | - Jean-Pierre Vaillancourt
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Université de Montréal, Montreal, QC, Canada
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Ornelas-Eusebio E, García-Espinosa G, Laroucau K, Zanella G. Characterization of commercial poultry farms in Mexico: Towards a better understanding of biosecurity practices and antibiotic usage patterns. PLoS One 2020; 15:e0242354. [PMID: 33259478 PMCID: PMC7707464 DOI: 10.1371/journal.pone.0242354] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2020] [Accepted: 10/30/2020] [Indexed: 01/21/2023] Open
Abstract
Mexico is one of the world’s major poultry producing countries. Two significant challenges currently facing the poultry industry are the responsible and judicious use of antimicrobials, and the potential occurrence of infectious disease outbreaks. For example, repeated outbreaks of highly pathogenic avian influenza virus subtype H7N3 have occurred in poultry since its first detection in Mexico in 2012. Both of these challenges can be addressed through good husbandry practices and the application of on-farm biosecurity measures. The aims of this study were: (i) to assess the biosecurity measures practiced across different types of poultry farms in Mexico, and (ii) to collect information regarding antimicrobial usage. A cross-sectional study was carried out through on-farm interviews on 43 poultry farms. A multiple correspondence analysis was performed to characterize the farms based on their pattern of biosecurity practices and antimicrobial usage. Three clusters of farms were identified using an agglomerative hierarchical cluster analysis. In each cluster, a specific farm type was predominant. The biosecurity measures that significantly differentiated the visited farms, thus allowing their clusterization, were: the use of personal protective equipment (e.g. face masks, hair caps, and eye protection), the requirement for a hygiene protocol before and after entering the farm, the use of exclusive working clothes by staff and visitors, footbath presence at the barn entrance, and the mortality disposal strategy. The more stringent the biosecurity measures on farms within a cluster, the fewer the farms that used antimicrobials. Farms with more biosecurity breaches used antimicrobials considered critically important for public health. These findings could be helpful to understand how to guide strategies to reinforce compliance with biosecurity practices identified as critical according to the farm type. We conclude by providing certain recommendations to improve on-farm biosecurity measures.
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Affiliation(s)
- Erika Ornelas-Eusebio
- Epidemiology Unit, Laboratory for Animal Health, ANSES, University Paris-Est, Maisons-Alfort, France
- Department of Avian Medicine and Poultry Husbandry, Faculty of Veterinary Medicine and Animal Production, National Autonomous University of Mexico, Coyoacan, CDMX, Mexico
- Bacterial Zoonosis Unit, Laboratory for Animal Health, ANSES, University Paris-Est, Maisons-Alfort, France
| | - Gary García-Espinosa
- Department of Avian Medicine and Poultry Husbandry, Faculty of Veterinary Medicine and Animal Production, National Autonomous University of Mexico, Coyoacan, CDMX, Mexico
| | - Karine Laroucau
- Bacterial Zoonosis Unit, Laboratory for Animal Health, ANSES, University Paris-Est, Maisons-Alfort, France
| | - Gina Zanella
- Epidemiology Unit, Laboratory for Animal Health, ANSES, University Paris-Est, Maisons-Alfort, France
- * E-mail:
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Delpont M, Blondel V, Robertet L, Duret H, Guerin JL, Vaillancourt JP, Paul MC. Biosecurity practices on foie gras duck farms, Southwest France. Prev Vet Med 2018; 158:78-88. [PMID: 30220399 DOI: 10.1016/j.prevetmed.2018.07.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2018] [Revised: 07/02/2018] [Accepted: 07/23/2018] [Indexed: 11/26/2022]
Abstract
On-farm biosecurity can be assessed by analyzing patterns of practices to better tailor technical advice to producers. Given their close contact with environmental and wildlife disease reservoirs, free-range duck farms are exposed to multiple risk factors of pathogen exposure that are rare or absent in indoor production. The recurrent emergence of Highly Pathogenic Avian Influenza (HPAI) viruses in Southeast Asia and Europe has emphasized the importance of farm-level biosecurity on free-range duck farms. This study was conducted on 46 French duck farms. The farms were visited and an 80-question survey was administered to assess biosecurity practices. Patterns of practices were explored with multiple correspondence analysis and hierarchical cluster analysis. Farms were assigned to one of three clusters in which specific farm types were overrepresented: farms specialized in rearing to grow-out phases and open-circuit full cycle (i.e., all production phases on the farm) farms in cluster 1, closed-circuit full cycle farms in cluster 2, and farms specialized in gavage in cluster 3. Differences in practices might be linked with differences in production constraints. This study provides a baseline assessment of biosecurity practices on foie gras duck farms in Southwest France and will help efforts to adapt biosecurity programs to farm types.
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Affiliation(s)
| | - Vincent Blondel
- Ecole Nationale Vétérinaire de Toulouse (ENVT), Toulouse, France
| | - Luc Robertet
- Ecole Nationale Vétérinaire de Toulouse (ENVT), Toulouse, France
| | - Hugues Duret
- Ecole Nationale Vétérinaire de Toulouse (ENVT), Toulouse, France
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Durr PA, Wibowo MH, Tarigan S, Artanto S, Rosyid MN, Ignjatovic J. Defining "Sector 3" Poultry Layer Farms in Relation to H5N1-HPAI-An Example from Java, Indonesia. Avian Dis 2017; 60:183-90. [PMID: 27309054 DOI: 10.1637/11134-050815-reg] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
To help guide surveillance and control of highly pathogenic avian influenza subtype H5N1 (H5N1-HPAI), the Food and Agriculture Organization of the United Nations in 2004 devised a poultry farm classification system based on a combination of production and biosecurity practices. Four "Sectors" were defined, and this scheme has been widely adopted within Indonesia to guide national surveillance and control strategies. Nevertheless, little detailed research into the robustness of this classification system has been conducted, particularly as it relates to independent, small to medium-sized commercial poultry farms (Sector 3). Through an analysis of questionnaire data collected as part of a survey of layer farms in western and central Java, all of which were classified as Sector 3 by local veterinarians, we provide benchmark data on what defines this sector. A multivariate analysis of the dataset, using hierarchical cluster analysis, identified three groupings of the farms, which were defined by a combination of production-and biosecurity-related variables, particularly those related to farm size and (the lack of) washing and disinfection practices. Nevertheless, the relationship between production-related variables and positive biosecurity practices was poor, and larger farms did not have an overall higher total biosecurity score than small or medium-sized ones. Further research is required to define the properties of poultry farms in Indonesia that are most closely related to effective biosecurity and the prevention of H5N1-HPAI.
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Affiliation(s)
- Peter A Durr
- A CSIRO, Australian Animal Health Laboratory, 5 Portarlington Road, Geelong, Australia, 3219
| | - Michael Haryadi Wibowo
- B Faculty of Veterinary Science, Gadjah Mada University, Jalan Fauna No. 2, Karangmalang, Yogyakarta, Indonesia, 55281
| | - Simson Tarigan
- C Indonesian Research Center for Veterinary Sciences, Jalan R. E. Martadinata No. 30, Bogor, Indonesia, 16114
| | - Sidna Artanto
- B Faculty of Veterinary Science, Gadjah Mada University, Jalan Fauna No. 2, Karangmalang, Yogyakarta, Indonesia, 55281
| | - Murni Nurhasanah Rosyid
- C Indonesian Research Center for Veterinary Sciences, Jalan R. E. Martadinata No. 30, Bogor, Indonesia, 16114
| | - Jagoda Ignjatovic
- D Faculty of Veterinary Science, University of Melbourne, 250 Princes Highway, Werribee, Australia, 3030
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Burbarelli MFC, Merseguel CEB, Ribeiro PAP, Lelis KD, Polycarpo GV, Carão ACP, Bordin RA, Fernandes AM, Souza RLM, Moro MEG, Albuquerque R. The Effects of Two Different Cleaning and Disinfection Programs on Broiler Performance and Microbiological Status of Broiler Houses. BRAZILIAN JOURNAL OF POULTRY SCIENCE 2015. [DOI: 10.1590/1516-635x1704575-580] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Gregers-Jensen L, Agger JF, Hammer ASV, Andresen L, Chrièl M, Hagberg E, Jensen MK, Hansen MS, Hjulsager CK, Struve T. Associations between biosecurity and outbreaks of canine distemper on Danish mink farms in 2012-2013. Acta Vet Scand 2015; 57:66. [PMID: 26423523 PMCID: PMC4589036 DOI: 10.1186/s13028-015-0159-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Accepted: 09/25/2015] [Indexed: 11/17/2022] Open
Abstract
Background During 8 months from July 2012 to February 2013, a major outbreak of canine distemper involving 64 mink farms occurred on the Danish peninsula of Jutland. The canine distemper outbreak was associated with exposure of farmed mink to infected wild carnivores and could represent a deficit in biosecurity on the mink farms. The aim of this study was to investigate the extent and association of specific biosecurity measures with the outbreak. The study was carried out in an epidemiological case–control design. The case group consisted of the 61 farms, which had a confirmed outbreak of canine distemper from July 2012 to February 2013. The control group included 54 farms without an outbreak of canine distemper in 2012 or 2013, selected as the closest geographical neighbour to a case farm. Results The results showed that significantly more control than case farms had vaccinated their mink against canine distemper virus. Mortality was only assessed on the case farms, and there was a non-significantly lower mortality on vaccinated farms than on the non-vaccinated farms. Furthermore, the proportion of farms with observations of wild red foxes (Vulpes vulpes) inside the farm enclosures were larger for case farms, indicating that the control farms had a better biosecurity or were not equally exposed to canine distemper virus. Generally, all farms had very few specific precautions at the gate entrance in respect to human visitors as well as animals. The use of biosecurity measures was very variable in both case and control farms. Not using plastic boot covers, presence of dogs and cats, presence of demarcated area for changing clothes when entering and leaving the farm area and presence of hand washing facilities significantly lowered the odds of the farm having a canine distemper virus outbreak. Conclusions The results of the study indicate that consistent use of correct vaccination strategies, implementation of biosecurity measures and limiting human and animal access to the mink farm can be important factors in reducing the risk for canine distemper outbreaks. Electronic supplementary material The online version of this article (doi:10.1186/s13028-015-0159-2) contains supplementary material, which is available to authorized users.
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Alonso C, Davies PR, Polson DD, Dee SA, Lazarus WF. Financial implications of installing air filtration systems to prevent PRRSV infection in large sow herds. Prev Vet Med 2013; 111:268-77. [DOI: 10.1016/j.prevetmed.2013.05.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2012] [Revised: 04/29/2013] [Accepted: 05/02/2013] [Indexed: 12/01/2022]
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Negro-Calduch E, Elfadaly S, Tibbo M, Ankers P, Bailey E. Assessment of biosecurity practices of small-scale broiler producers in central Egypt. Prev Vet Med 2013; 110:253-62. [DOI: 10.1016/j.prevetmed.2012.11.014] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2012] [Revised: 10/24/2012] [Accepted: 11/05/2012] [Indexed: 10/27/2022]
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Evaluation of strategies to enhance biosecurity compliance on poultry farms in Québec: Effect of audits and cameras. Prev Vet Med 2012; 103:208-18. [DOI: 10.1016/j.prevetmed.2011.08.004] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2011] [Revised: 07/28/2011] [Accepted: 08/12/2011] [Indexed: 11/21/2022]
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Fasina FO, Ali AM, Yilma JM, Thieme O, Ankers P. The cost-benefit of biosecurity measures on infectious diseases in the Egyptian household poultry. Prev Vet Med 2011; 103:178-91. [PMID: 21982688 DOI: 10.1016/j.prevetmed.2011.09.016] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2011] [Revised: 09/02/2011] [Accepted: 09/16/2011] [Indexed: 11/16/2022]
Abstract
Increased animal intensification presents with increasing risks of animal diseases. The Egyptian household poultry is peculiar in its management style and housing and this present with particular challenges of risk of infection to both the flock and humans. Biosecurity remains one of the most important means of reducing risks of infection in the household poultry, however not much information is available to support its feasibility at the household level of production. In this study financial feasibilities of biosecurity were modeled and evaluated based on certain production parameters. Risks of particular importance to the household poultry were categorized and highly pathogenic avian influenza H5N1 was the most risky disease while people-related risk was the most important risk category. It was observed that basic biosecurity measures were applicable in the household poultry and it would be 8.45 times better to implement biosecurity than to do nothing against HPAI H5N1; 4.88 times better against Newcastle disease and 1.49 times better against coccidiosis. Sensitivity analyses proved that the household poultry project was robust and would withstand various uncertainties. An uptake pathway for basic biosecurity was suggested. The outcome of this work should support decisions to implement biosecurity at the household sector of poultry production.
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Affiliation(s)
- F O Fasina
- Emergency Centre for Transboundary Animal Diseases (ECTAD), FAO, Dokki-Cairo, Cairo, Egypt.
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Racicot M, Venne D, Durivage A, Vaillancourt JP. Description of 44 biosecurity errors while entering and exiting poultry barns based on video surveillance in Quebec, Canada. Prev Vet Med 2011; 100:193-9. [DOI: 10.1016/j.prevetmed.2011.04.011] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2011] [Revised: 04/02/2011] [Accepted: 04/13/2011] [Indexed: 11/24/2022]
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Watson D, Boohene C, Denning S, Stringham S. Tank Mixes: Consequences of Using Insecticide and Disinfectant Mixtures to Reduce Flies and Bacteria. J APPL POULTRY RES 2008. [DOI: 10.3382/japr.2007-00044] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Andrew Thompson RC, Owen IL, Puana I, Banks D, Davis TME, Reid SA. Parasites and biosecurity--the example of Australia. Trends Parasitol 2003; 19:410-6. [PMID: 12957518 DOI: 10.1016/s1471-4922(03)00197-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Biosecurity issues as they impact on agriculture, health and the environment are becoming increasingly important. Surveillance is crucial in maintaining a country's biosecurity and this article looks at some of the issues in the context of Australia and its neighbors in the Asia-Pacific region, and emerging threats from parasitic diseases. The important threats to agriculture, public health and wildlife are highlighted, and attention is given to how future surveillance activities must be undertaken on a regional basis and involve neighboring countries if they are to be effective and lead to the protection of both the trade and health of the population.
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Affiliation(s)
- R C Andrew Thompson
- World Health Organization Collaborating Centre for the Molecular Epidemiology of Parasitic Infections, Division of Veterinary and Biomedical Sciences, Murdoch University, WA, Australia
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Abstract
In this study, 151 (18.6%) of 814 ceca obtained during in-line processing of 28 broiler (Hybro G, Avian, Arbor acres, and Cobb breeds) and 5 layer (Ross, Tetra SL, Isa Brown, and Brown Nick breeds) flocks in Turkey were found to be contaminated with four different Salmonella serovars. Only Salmonella enterica subsp. enterica Serovar Enteritidis (Salmonella Enteritidis) was recovered from layer birds, whereas Salmonella Enteritidis (81.5%). Salmonella Agona (7.6%), Salmonella Thompson (10.1%), and Salmonella Sarajane (0.8%) were isolated from broiler birds. Isolations of Salmonella Agona and Salmonella Thompson from poultry are reported for the first time in Turkey. The isolation of Salmonella Sarajane from chickens is the first report in the world. The standard method of National Poultry Improvement Plan, U.S. Department of Agriculture, was used to detect Salmonella from chicken cecal samples. Primary and delayed secondary enrichments (PE and DSE) were done in tetrathionate-Hajna broth (TTHB). Two different agar media, xylose lysine tergitol 4 (XLT4) and brilliant green with novobiocin (BGN) were used to observe, and compared for their isolation and selective differentiation of, Salmonella-suspected colonies. Isolated salmonellae were then biotyped and serotyped. Ninety-one and 151 salmonellae were isolated with XLT4 agar after PE and DSE, respectively. From the same samples, BGN agar was able to detect only 50 and 131 Salmonella after PE and DSE, respectively. The isolation rate with XLT4 was 11.2% (P < 0.01) with PE, and this rate increased to 18.6% after DSE. Also, the PE isolation rate (11.2%) with XLT4 agar was significantly higher (P < 0.01) than PE with BGN agar (6.1%). Salmonella was isolated from 39.3% (11 of 28) of the broiler flocks and from 60.0% (3 of 5) of the layers. The detection sensitivity of the isolation method was determined as 1 CFU g(-1) experimentally. These data demonstrate the presence of Salmonella Enteritidis, Salmonella Thompson, Salmonella Agona, and Salmonella Sarajane in chicken flocks in Turkey.
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Affiliation(s)
- K T Carli
- Department of Microbiology, Faculty of Veterinary Medicine, Uludag University, Bursa, Turkey.
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Sen S, Shane SM, Scholl DT, Hugh-Jones ME, Gillespie JM. Evaluation of alternative strategies to prevent Newcastle disease in Cambodia. Prev Vet Med 1998; 35:283-95. [PMID: 9689660 DOI: 10.1016/s0167-5877(98)00065-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Velogenic viscerotropic Newcastle disease (vvNCD), which is endemic in Cambodia, can be prevented in theory by a combination of biosecurity and immunization of broiler flocks. The relative contribution of appropriate biosecurity and effective vaccination was quantified at the farm level, applying realistic projections for capital investment, fixed and variable production costs and losses following infection. Non-protected broiler flocks generate a loss when the probability of vvNCD infection exceeds 0.4. Applying both biosecurity and effective vaccination would sustain profitability up to a probability of exposure of 1.0. The benefit to cost ratios for alternative strategies were evaluated for a range of probabilities of exposure to vvNCD extending from 0.1 to 1.0. The benefit-to-cost ratio for biosecurity exceeded unity at a risk of exposure exceeding 0.1, and 0.2 for vaccination and the combination of vaccination and biosecurity respectively. A sensitivity analysis demonstrated that the efficiency of protection, feed cost, and financial consequences of infection markedly affected the projected benefit-to-cost ratios associated with alternative methods of prevention.
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Affiliation(s)
- S Sen
- Department of Epidemiology and Community Health, School of Veterinary Medicine, Louisiana State University, Baton Rouge 70803, USA
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Dimitri RA, Gabal MA, Saleh N. Effect of aflatoxin ingestion in feed on body weight gain and tissue residues in rabbits. Mycoses 1998; 41:87-91. [PMID: 9610142 DOI: 10.1111/j.1439-0507.1998.tb00384.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The effect of a subclinical dose of aflatoxin on body weight gain and risk assessment of aflatoxin in muscle tissue for food safety were the focus of the study. Thirty New Zealand rabbits, 2 months old, were used. A group of 24 rabbits was fed aflatoxin 2 p.p.m. day-1 for a period of 4 months. The weights of the individual aflatoxin-fed rabbits and those of the control group were recorded weekly. Aflatoxin was withdrawn from a group of six rabbits chosen at random for a period of 4 weeks before the termination of the experiment. All rabbits were necropsied at the end of the study for gross and microscopic changes of the internal organs. Samples of muscle tissue were also collected and analysed chemically for aflatoxin using thin-layer chromatography. Significant weight loss equivalent to 13% mortality was found in the aflatoxin-fed rabbits. Characteristic pathological changes were found. Aflatoxins B1 and G2 were detected in muscle tissue at alarming concentrations far exceeding the permissible levels in food for human consumption in the aflatoxin-fed group. No detectable aflatoxins were found in the aflatoxin-withdrawal group.
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Affiliation(s)
- R A Dimitri
- Veterinary Serum and Vaccine Research Institute, Abbasia, Cairo, Egypt
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Abstract
A questionnaire for farm managers was designed, to obtain information regarding biosecurity on Ontario commercial broiler chicken and turkey operations, and then pre-tested. The questions that could be validated were verifiable by seeing the facility, by using farm records or by interviewing technical personnel other than the survey respondent. The survey was validated using a convenience sample of 24 farms from two companies. For 15 questions with dichotomous responses, the sensitivity ranged from 16.7 to 100%; the specificity ranged from 0 to 100%. For example, fences and gates seen during the farm visit were not accurately reported on the survey (poor sensitivity). Chance-corrected agreement was low (kappa < 0.4) for 34 questions, fair to good (0.4 < kappa < 0.8) for 25 questions, and excellent (kappa > 0.8) for seven questions. The percent agreement for questions where only one of the possible options was observed on validation ranged from 60.9 to 100%. Five questions with continuous numeric variables were analysed. A difference was observed (P < 0.1) between the survey and validation data for three questions regarding the number of birds, the bird sources and the downtime between flocks. In spite of pre-testing, the lack of clear wording and the absence of definitions for technical terms appeared to reduce validity. Response bias seems to be an issue with biosecurity surveys. The value of validating questionnaires before their use in epidemiologic research is confirmed.
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Affiliation(s)
- R Nespeca
- Department of Population Medicine, University of Guelph, Ontario, Canada
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Risk factors identified as source of new infections (area spread) with pseudorabies (Aujeszky's disease) virus in 50 swine herds in a contiguous geographical area of Ohio. Prev Vet Med 1995. [DOI: 10.1016/0167-5877(94)00432-i] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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