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Rasmussen P, Barkema HW, Osei PP, Taylor J, Shaw AP, Conrady B, Chaters G, Muñoz V, Hall DC, Apenteng OO, Rushton J, Torgerson PR. Global losses due to dairy cattle diseases: A comorbidity-adjusted economic analysis. J Dairy Sci 2024; 107:6945-6970. [PMID: 38788837 PMCID: PMC11382338 DOI: 10.3168/jds.2023-24626] [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: 12/28/2023] [Accepted: 04/01/2024] [Indexed: 05/26/2024]
Abstract
An economic simulation was carried out over 183 milk-producing countries to estimate the global economic impacts of 12 dairy cattle diseases and health conditions: mastitis (subclinical and clinical), lameness, paratuberculosis (Johne's disease), displaced abomasum, dystocia, metritis, milk fever, ovarian cysts, retained placenta, and ketosis (subclinical and clinical). Estimates of disease impacts on milk yield, fertility, and culling were collected from the literature, standardized, meta-analyzed using a variety of methods ranging from simple averaging to random-effects models, and adjusted for comorbidities to prevent overestimation. These comorbidity-adjusted disease impacts were then combined with a set of country-level estimates for lactational incidence or prevalence or both, herd characteristics, and price estimates within a series of Monte Carlo simulations that estimated and valued the economic losses due to these diseases. It was estimated that total annual global losses are US$65 billion (B). Subclinical ketosis, clinical mastitis, and subclinical mastitis were the costliest diseases modeled, resulting in mean annual global losses of approximately US$18B, US$13B, and US$9B, respectively. Estimated global annual losses due to clinical ketosis, displaced abomasum, dystocia, lameness, metritis, milk fever, ovarian cysts, paratuberculosis, and retained placenta were estimated to be US$0.2B, US$0.6B, US$0.6B, US$6B, US$5B, US$0.6B, US$4B, US$4B, and US$3B, respectively. Without adjustment for comorbidities, when statistical associations between diseases were disregarded, mean aggregate global losses would have been overestimated by 45%. Although annual losses were greatest in India (US$12B), the United States (US$8B), and China (US$5B), depending on the measure of losses used (losses as a percentage of gross domestic product, losses per capita, losses as a percentage of gross milk revenue), the relative economic burden of these dairy cattle diseases across countries varied markedly.
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Affiliation(s)
- Philip Rasmussen
- Section of Animal Welfare and Disease Control, Department Veterinary and Animal Sciences, University of Copenhagen, Copenhagen DK-1870, Denmark; Section of Epidemiology, Vetsuisse Faculty, University of Zurich, Zurich CH 0857, Switzerland; Global Burden of Animal Diseases (GBADs), Liverpool L69 3BX, United Kingdom.
| | - Herman W Barkema
- Faculty of Veterinary Medicine, University of Calgary, Calgary, AB T2N 4Z6, Canada
| | - Prince P Osei
- School of Mathematics and Statistics, Carleton University, Ottawa, ON K1S 5B6, Canada
| | - James Taylor
- Agri-Food and Biosciences Institute (AFBI), Belfast BT9 5PX, United Kingdom
| | - Alexandra P Shaw
- Department of Livestock and One Health, Institute of Infection, Veterinary & Ecological Sciences, University of Liverpool, Liverpool L69 3BX, United Kingdom; Infection Medicine, Biomedical Sciences, Edinburgh Medical School, University of Edinburgh, Edinburgh EH16 4SB, United Kingdom
| | - Beate Conrady
- Section of Animal Welfare and Disease Control, Department Veterinary and Animal Sciences, University of Copenhagen, Copenhagen DK-1870, Denmark
| | - Gemma Chaters
- Global Burden of Animal Diseases (GBADs), Liverpool L69 3BX, United Kingdom; Department of Livestock and One Health, Institute of Infection, Veterinary & Ecological Sciences, University of Liverpool, Liverpool L69 3BX, United Kingdom
| | - Violeta Muñoz
- Section of Epidemiology, Vetsuisse Faculty, University of Zurich, Zurich CH 0857, Switzerland; Global Burden of Animal Diseases (GBADs), Liverpool L69 3BX, United Kingdom
| | - David C Hall
- Faculty of Veterinary Medicine, University of Calgary, Calgary, AB T2N 4Z6, Canada
| | - Ofosuhene O Apenteng
- Section of Animal Welfare and Disease Control, Department Veterinary and Animal Sciences, University of Copenhagen, Copenhagen DK-1870, Denmark
| | - Jonathan Rushton
- Global Burden of Animal Diseases (GBADs), Liverpool L69 3BX, United Kingdom; Department of Livestock and One Health, Institute of Infection, Veterinary & Ecological Sciences, University of Liverpool, Liverpool L69 3BX, United Kingdom
| | - Paul R Torgerson
- Section of Epidemiology, Vetsuisse Faculty, University of Zurich, Zurich CH 0857, Switzerland; Global Burden of Animal Diseases (GBADs), Liverpool L69 3BX, United Kingdom
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Navarro León A, Muñoz M, Iglesias N, Blanco-Vázquez C, Balseiro A, Milhano Santos F, Ciordia S, Corrales FJ, Iglesias T, Casais R. Proteomic Serum Profiling of Holstein Friesian Cows with Different Pathological Forms of Bovine Paratuberculosis Reveals Changes in the Acute-Phase Response and Lipid Metabolism. J Proteome Res 2024; 23:2762-2779. [PMID: 37863471 PMCID: PMC11301775 DOI: 10.1021/acs.jproteome.3c00244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 09/18/2023] [Accepted: 09/22/2023] [Indexed: 10/22/2023]
Abstract
The lack of sensitive diagnostic methods to detect Mycobacterium avium subsp. paratuberculosis (Map) subclinical infections has hindered the control of paratuberculosis (PTB). The serum proteomic profiles of naturally infected cows presenting focal and diffuse pathological forms of PTB and negative controls (n = 4 per group) were analyzed using TMT-6plex quantitative proteomics. Focal and diffuse are the most frequent pathological forms in subclinical and clinical stages of PTB, respectively. One (focal versus (vs.) control), eight (diffuse vs. control), and four (focal vs. diffuse) differentially abundant (DA) proteins (q-value < 0.05) were identified. Ingenuity pathway analysis of the DA proteins revealed changes in the acute-phase response and lipid metabolism. Six candidate biomarkers were selected for further validation by specific ELISA using serum from animals with focal, multifocal, and diffuse PTB-associated lesions (n = 108) and controls (n = 56). Overall, the trends of the serum expression levels of the selected proteins were consistent with the proteomic results. Alpha-1-acid glycoprotein (ORM1)-based ELISA, insulin-like growth factor-binding protein 2 (IGFBP2)-based ELISA, and the anti-Map ELISA had the best diagnostic performance for detection of animals with focal, multifocal, and diffuse lesions, respectively. Our findings identify potential biomarkers that improve diagnostic sensitivity of PTB and help to elucidate the mechanisms involved in PTB pathogenesis.
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Affiliation(s)
- Alejandra
Isabel Navarro León
- Center
for Animal Biotechnology, Servicio Regional
de Investigación y Desarrollo Agroalimentario [SERIDA], 33394 Deva, Asturias, Spain
| | - Marta Muñoz
- Center
for Animal Biotechnology, Servicio Regional
de Investigación y Desarrollo Agroalimentario [SERIDA], 33394 Deva, Asturias, Spain
| | - Natalia Iglesias
- Center
for Animal Biotechnology, Servicio Regional
de Investigación y Desarrollo Agroalimentario [SERIDA], 33394 Deva, Asturias, Spain
| | - Cristina Blanco-Vázquez
- Center
for Animal Biotechnology, Servicio Regional
de Investigación y Desarrollo Agroalimentario [SERIDA], 33394 Deva, Asturias, Spain
| | - Ana Balseiro
- Departamento
de Sanidad Animal, Facultad de Veterinaria, Universidad de León, 24071 León, Spain
| | - Fátima Milhano Santos
- Functional
Proteomics Laboratory, National Center for Biotechnology, Consejo Superior de Investigaciones Científicas [CSIC],
Proteored-ISCIII, 28049 Madrid, Spain
| | - Sergio Ciordia
- Functional
Proteomics Laboratory, National Center for Biotechnology, Consejo Superior de Investigaciones Científicas [CSIC],
Proteored-ISCIII, 28049 Madrid, Spain
| | - Fernando J. Corrales
- Functional
Proteomics Laboratory, National Center for Biotechnology, Consejo Superior de Investigaciones Científicas [CSIC],
Proteored-ISCIII, 28049 Madrid, Spain
| | - Tania Iglesias
- Unidad
de Consultoría Estadística, Servicios Científico-técnicos, Universidad de Oviedo, Campus de Gijón, 33203 Gijón, Asturias, Spain
| | - Rosa Casais
- Center
for Animal Biotechnology, Servicio Regional
de Investigación y Desarrollo Agroalimentario [SERIDA], 33394 Deva, Asturias, Spain
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Žele Vengušt D, Krt B, Blagus R, Vengušt G, Bandelj P. Seroprevalence of infectious pathogens of zoonotic and veterinary importance in wild ruminants from Slovenia. Front Vet Sci 2024; 11:1415304. [PMID: 38915887 PMCID: PMC11194780 DOI: 10.3389/fvets.2024.1415304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2024] [Accepted: 05/30/2024] [Indexed: 06/26/2024] Open
Abstract
Introduction Wildlife represents an increasingly important source of pathogens of medical and veterinary importance. Surveillance in wildlife offers an insight on current epidemiological status of selected pathogens and help to prevent spillovers to humans and livestock. Material and methods Our study included 312 wild ruminants belonging to five species: Roe deer (n = 134), red deer (n = 113), Alpine chamois (n = 53), European mouflon (n = 10) and Alpine ibex (n = 2). Seven pathogens that may have profound effect on human/livestock health and economic viability of the farms were tested using serological methods. Results Antibodies against Toxoplasma gondii, Neospora caninum, Coxiella burnetii, Brucella spp., Chlamydophila abortus, Mycobacterium avium subsp. paratuberculosis (MAP) and Mycobacterium bovis were detected in 34.62% (108/312), 0.96% (3/312), 2.24% (7/312), 0, 0.96% (3/312), 0, 0.64% (2/312) of animals tested, respectively. Because of low prevalences, risk factors were assessed only for T. gondii. Sex (female>male) and species (roe deer>red deer, roe deer>Alpine chamois) were significantly associated with the T. gondii positive outcome, while age was not. Discussion Adult males had the lowest T. gondii prevalence which offers future research opportunities. The lower seroprevalence of most investigated pathogens suggests game meat, if properly cooked, as being relatively safe for human consumption. This is the first study investigating the seroprevalence and associated risk factors of selected pathogens in wild ruminants in Slovenia.
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Affiliation(s)
- Diana Žele Vengušt
- Institute of Pathology, Wild Animals, Fish and Bees, Veterinary Faculty, University of Ljubljana, Ljubljana, Slovenia
| | - Brane Krt
- Institute of Microbiology and Parasitology, Veterinary Faculty, University of Ljubljana, Ljubljana, Slovenia
| | - Rok Blagus
- Institute for Biostatistics and Medical Informatics, University of Ljubljana, Ljubljana, Slovenia
- Faculty of Mathematics, Natural Sciences and Information Technologies, University of Primorska, Koper, Slovenia
| | - Gorazd Vengušt
- Institute of Pathology, Wild Animals, Fish and Bees, Veterinary Faculty, University of Ljubljana, Ljubljana, Slovenia
| | - Petra Bandelj
- Institute of Microbiology and Parasitology, Veterinary Faculty, University of Ljubljana, Ljubljana, Slovenia
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Martins E, Oliveira P, Correia-Gomes C, Mendonça D, Ribeiro JN. Association of Mycobacterium avium paratuberculosis serostatus with age at first calving, calving interval, and milk production in dairy cows. J Dairy Sci 2024; 107:3916-3926. [PMID: 38331177 DOI: 10.3168/jds.2023-23516] [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: 03/21/2023] [Accepted: 12/03/2023] [Indexed: 02/10/2024]
Abstract
Mycobacterium avium ssp. paratuberculosis (MAP) is the causative agent of bovine paratuberculosis, also known as Johne's disease. This infection is responsible for negative effects, ranging from reduction of milk production to reproductive compromise and increased susceptibility to other diseases such as mastitis. Contradictory information on the association between this infection and reproductive performance has been reported in dairy cows. The aim of this work was to investigate associations between individual cow MAP seropositivity and lifetime reproduction and production performance. The MAP serum ELISA (IDEXX MAP Ac) results from all the 13,071 adult cows present on 191 farms and corresponding birth- and calving-date records obtained from the National Association for Genetic Improvement of Dairy Cattle were used. Cows and farms were classified as positive or negative, based on ELISA results. Outcomes assessed were age at first calving (AFC), intercalving intervals (ICI) from first to fourth interval, and average milk production per day of productive cycle (Milk-305/ICI, a ratio between 305-d corrected milk production and the number of days of the respective calving interval). Multilevel mixed models were used to investigate the association of cow MAP status with AFC, ICI, and Milk-305/ICI. Three levels were considered in the models: "measurement occasion," the first level, was nested within cows and cows were nested within farms. The "measurement occasion" is the time point to which all the observed measures (between 2 successive parturitions, such as milk production and somatic cell count) were referred. Our results indicate that MAP-positive cows have a significantly lower 14-d mean AFC than MAP-negative cows. The overall average ICI in our study was 432.5 d (standard deviation: 94.6). The average ICI, from first to fourth, was not significantly affected by MAP seropositivity. No significant effect of MAP positivity was found on the overall ICI. In relation to Milk-305/ICI, MAP-positive cows did not produce significantly less milk than negative cows across their productive lifetime. We observed higher but nonsignificant Milk-305/ICI (kg/d) in MAP-positive cows. In our study, the proportion of MAP-positive cows within lactations remained similar across all lactations, suggesting that seropositivity did not increased drop-off rate.
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Affiliation(s)
- Elisabete Martins
- Instituto de Ciências Biomédicas Abel Salazar (ICBAS), 4050-313 Porto, Portugal; EPIUnit-Instituto de Saúde Pública da Universidade do Porto (ISPUP), 4050-600 Porto, Portugal; Departement of Veterinary Sciences, Escola Universitária Vasco da Gama (EUVG), 3020-210 Coimbra, Portugal.
| | - Pedro Oliveira
- Instituto de Ciências Biomédicas Abel Salazar (ICBAS), 4050-313 Porto, Portugal; EPIUnit-Instituto de Saúde Pública da Universidade do Porto (ISPUP), 4050-600 Porto, Portugal; Laboratório para a Investigação Integrativa e Translacional em Saúde Populacional (ITR), 4050-313 Porto, Portugal
| | | | - Denisa Mendonça
- Instituto de Ciências Biomédicas Abel Salazar (ICBAS), 4050-313 Porto, Portugal; EPIUnit-Instituto de Saúde Pública da Universidade do Porto (ISPUP), 4050-600 Porto, Portugal; Laboratório para a Investigação Integrativa e Translacional em Saúde Populacional (ITR), 4050-313 Porto, Portugal
| | - João Niza Ribeiro
- Instituto de Ciências Biomédicas Abel Salazar (ICBAS), 4050-313 Porto, Portugal; EPIUnit-Instituto de Saúde Pública da Universidade do Porto (ISPUP), 4050-600 Porto, Portugal; Laboratório para a Investigação Integrativa e Translacional em Saúde Populacional (ITR), 4050-313 Porto, Portugal
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Chen Y, Hou L, Khalid AK, Robertson ID, Zhao Y, Chen X, Guo A. Individual- and Herd-Level Milk ELISA Test Status and Incidence for Paratuberculosis in Hubei Province, China. Vet Sci 2024; 11:202. [PMID: 38787174 PMCID: PMC11125760 DOI: 10.3390/vetsci11050202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2024] [Revised: 04/23/2024] [Accepted: 05/02/2024] [Indexed: 05/25/2024] Open
Abstract
Mycobacterium avium subsp. paratuberculosis (MAP) is responsible for the persistent infectious illness known as bovine paratuberculosis, which is one of the most easily overlooked diseases in China amid a lack of epidemiological data. In this study, we evaluated the agreement of milk and blood antibody tests for paratuberculosis and showed an overall agreement of 92.0%, with a 95.0% negative coincidence rate and a 78.6% positive coincidence rate. The milk test was then used to examine the prevalence and incidence of dairy cows in Hubei Province, China. We found that, at the individual level, the highest lacto-prevalence reached up to 22.9%; the farm-level prevalence was as high as 92.3% (12/13) and 84.6% (11/13) in January and April 2018, respectively. The total incidence risk of all farms was 6% per three months. We also found that large-scale farms had a significantly lower prevalence and incidence than small-scale farms. Finally, the correlation between paratuberculosis and milk quality was evaluated, and we confirmed that MAP can significantly alter milk quality and raise somatic cell counts in the milk. This study provides valuable information for assessing the prevalence and incidence risk of paratuberculosis in China. It further provides an essential basis for calling for the prevention and control of paratuberculosis in China.
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Affiliation(s)
- Yingyu Chen
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (Y.C.); (L.H.); (A.K.K.); (Y.Z.); (X.C.)
- National Animal Tuberculosis Para-Reference Laboratory (Wuhan), Hubei International Scientific and Technological Cooperation Base of Veterinary Epidemiology, Huazhong Agricultural University, Wuhan 430070, China;
| | - Liyue Hou
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (Y.C.); (L.H.); (A.K.K.); (Y.Z.); (X.C.)
| | - Abdul Karim Khalid
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (Y.C.); (L.H.); (A.K.K.); (Y.Z.); (X.C.)
| | - Ian Duncan Robertson
- National Animal Tuberculosis Para-Reference Laboratory (Wuhan), Hubei International Scientific and Technological Cooperation Base of Veterinary Epidemiology, Huazhong Agricultural University, Wuhan 430070, China;
- School of Veterinary Medicine, Murdoch University, Murdoch, WA 6150, Australia
| | - Yuhao Zhao
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (Y.C.); (L.H.); (A.K.K.); (Y.Z.); (X.C.)
| | - Xi Chen
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (Y.C.); (L.H.); (A.K.K.); (Y.Z.); (X.C.)
- National Animal Tuberculosis Para-Reference Laboratory (Wuhan), Hubei International Scientific and Technological Cooperation Base of Veterinary Epidemiology, Huazhong Agricultural University, Wuhan 430070, China;
| | - Aizhen Guo
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (Y.C.); (L.H.); (A.K.K.); (Y.Z.); (X.C.)
- National Animal Tuberculosis Para-Reference Laboratory (Wuhan), Hubei International Scientific and Technological Cooperation Base of Veterinary Epidemiology, Huazhong Agricultural University, Wuhan 430070, China;
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Griss S, Knific T, Buzzell A, Carmo LP, Schüpbach-Regula G, Meylan M, Ocepek M, Thomann B. A scoping review on associations between paratuberculosis and productivity in cattle. Front Vet Sci 2024; 11:1352623. [PMID: 38756521 PMCID: PMC11097669 DOI: 10.3389/fvets.2024.1352623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Accepted: 04/11/2024] [Indexed: 05/18/2024] Open
Abstract
Paratuberculosis (PTB), or Johne's disease, is a disease with worldwide distribution caused by Mycobacterium avium subsp. paratuberculosis (MAP) that leads to chronic enteritis, primarily in ruminants. Even subclinical infection significantly reduces the animals' performance, and consequences of the disease lead to high economic losses for the cattle industry. To estimate the economic burden of bovine PTB and to evaluate the benefits of a potential control program, accurate estimates of the production effects associated with the disease are required. Therefore, the aim of this scoping review was to provide a comprehensive overview of associations between MAP infection and production parameters in cattle. The studies were collected from three electronic databases. Of the total 1,605 identified studies, 1,432 did not meet the set criteria in the title and abstract screening and a further 106 were excluded during full-text review. Finally, data on 34 different production parameters were extracted from 67 publications. Results show that the magnitude of reported performance losses varies depending on several factors, such as the type of diagnostic test applied, disease status or number of lactations. Studies reported a reduction in milk yield, changes in milk quality (e.g., higher somatic cell count, lower amount of produced milk fat and protein), reduced fertility (e.g., prolonged calving interval and service period, higher abortion rate and calving difficulties), reduced weaning weight, slaughter weight and slaughter value, or a higher risk for mastitis. Results from the studies included in our review show a median decrease of milk yield per infected cow of -452 kg/lactation for raw and -405 kg/lactation for modeled data. Similarly, the amount of produced milk protein fell by a median of -14.41 kg/lactation for modeled data and the amount of produced milk fat by a median of -13.13 kg/lactation. The reviewed studies revealed a prolonged calving interval by around 30 days and a 1.5 to 3 times higher likeliness of culling per lactation in PTB positive animals. Results from this scoping review provide evidence-based inputs for the development of economic models aiming at the estimation of the costs and benefits associated with different disease control scenarios for PTB.
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Affiliation(s)
- Silja Griss
- Vetsuisse Faculty, Veterinary Public Health Institute, University of Bern, Bern, Switzerland
- Graduate School for Cellular and Biomedical Sciences, University of Bern, Bern, Switzerland
| | - Tanja Knific
- Veterinary Faculty, Institute of Food Safety, Feed and Environment, University of Ljubljana, Ljubljana, Slovenia
| | - Anne Buzzell
- Vetsuisse Faculty, Veterinary Public Health Institute, University of Bern, Bern, Switzerland
| | | | | | - Mireille Meylan
- Clinic for Ruminants, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Matjaž Ocepek
- Veterinary Faculty, Institute of Microbiology and Parasitology, University of Ljubljana, Ljubljana, Slovenia
| | - Beat Thomann
- Vetsuisse Faculty, Veterinary Public Health Institute, University of Bern, Bern, Switzerland
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7
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Veres K, Lang Z, Monostori A, Kostoulas P, Ózsvári L. Bayesian latent class modelling of true prevalence in animal subgroups with application to bovine paratuberculosis infection. Prev Vet Med 2024; 224:106133. [PMID: 38340463 DOI: 10.1016/j.prevetmed.2024.106133] [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: 04/03/2023] [Revised: 01/05/2024] [Accepted: 01/22/2024] [Indexed: 02/12/2024]
Abstract
The prevalence of an infectious disease of animals living in separate groups (e.g. herds) is naturally analyzed using a Bayesian hierarchical latent class model. We propose an extension to this methodology by including subgroup level prevalence measures within the groups of animals. As an application illustrating the merits of our methodology, we reassessed the prevalence of bovine paratuberculosis (PTBC) infection in Hungarian commercial dairy farms. Our aim was to consolidate previous findings using a large amount of recent data and priors based on historical data. To model the subgroup level infection prevalence within animal groups, we considered correlated prevalences following beta distributions derived from independent normally distributed random herd effects. In the application, infection status of herds was handled as latent classes, multiparous and primiparous cows as within-herd subgroups. The novel methodology allows us to estimate both the mean and median conditional within-herd true prevalence (CWHP) related to each animal subgroup as well as other measures characterizing the interrelation of subgroups. The results of the application aligned with the findings of the former PTBC study, while the more recent and considerably larger dataset and the use of historical priors increased the reliability of the results. The STAN and JAGS codes of the application are available in Supplementary material.
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Affiliation(s)
- Katalin Veres
- Department of Biostatistics, University of Veterinary Medicine Budapest, Budapest, Hungary.
| | - Zsolt Lang
- Department of Biostatistics, University of Veterinary Medicine Budapest, Budapest, Hungary
| | | | | | - László Ózsvári
- Department of Veterinary Forensics and Economics, University of Veterinary Medicine Budapest, Budapest, Hungary; National Laboratory of Infectious Animal Diseases, Antimicrobial Resistance, Veterinary Public Health and Food Chain Safety, University of Veterinary Medicine Budapest
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Tigani-Asil ETAE, Abdelwahab GED, Abdu EHAM, Terab AMA, Khalil NAH, Marri ZJMA, Yuosf MF, Shah AAM, Khalafalla AI, Ishag HZA. Pathological, microscopic, and molecular diagnosis of paratuberculosis/John's disease in naturally infected dromedary camel ( Camelus dromedarius). Vet World 2023; 16:1277-1283. [PMID: 37577185 PMCID: PMC10421554 DOI: 10.14202/vetworld.2023.1277-1283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2023] [Accepted: 05/15/2023] [Indexed: 08/15/2023] Open
Abstract
Background and Aim Paratuberculosis (PTB) or John's disease is a chronic disease of ruminants impeding the reproduction and productivity of the livestock sector worldwide. Since there is a lack of pathological studies explaining the nature and development of the disease in camels, this study aimed to highlight the anatomopathological changes of PTB in camels, which may help in verifying and validating some diagnostic tests used to detect the etiology of the disease in camel tissues. Materials and Methods In August 2017, at Alselaa border's Veterinary Clinic of Al Dhafra Region, Western Abu Dhabi, UAE, one imported culled she-camel of 2 years old was subjected to clinical, microscopic, and anatomopathological investigations along with real-time quantitative polymerase chain reaction (q-PCR) to confirm the infection and correlate between clinical signs and pathological lesions of the PTB in dromedary camels. Results Clinically, typical clinical signs compliant with the pathognomonic gross and histologic lesions of PTB were seen in naturally infected dromedary camel. As presumptive diagnosis microscopically, acid-fast coccobacillus bacterium clumps were demonstrated in direct fecal smears as well as in scraped mucosal and crushed mesenteric lymph node films, and in histopathological sections prepared from a necropsied animal and stained by Ziehl-Neelsen stain. Free and intracellular acid-fast clump phagosomes were further confirmed as Mycobacterium avium subsp. paratuberculosis by q-PCR. Conclusion Clinical signs and pathological lesions of paratuberculosis in a dromedary camel were found to be similar to those of the other susceptible hosts.
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Affiliation(s)
- El Tigani Ahmed El Tigani-Asil
- Biosecurity Affairs Division, Development and Innovation Sector, Abu Dhabi Agriculture and Food Safety Authority, Abu Dhabi, United Arab Emirates
| | - Ghada El Derdiri Abdelwahab
- Biosecurity Affairs Division, Development and Innovation Sector, Abu Dhabi Agriculture and Food Safety Authority, Abu Dhabi, United Arab Emirates
| | - El Hadi Ahmed Mohamed Abdu
- Extension Services and Animal Health Division, Animal Wealth Sector, Abu Dhabi Agriculture and Food Safety Authority, Abu Dhabi, United Arab Emirates
| | - Abdelnasir Mohammed Adam Terab
- Biosecurity Affairs Division, Development and Innovation Sector, Abu Dhabi Agriculture and Food Safety Authority, Abu Dhabi, United Arab Emirates
| | - Nasareldien Altaib Hussein Khalil
- Biosecurity Affairs Division, Development and Innovation Sector, Abu Dhabi Agriculture and Food Safety Authority, Abu Dhabi, United Arab Emirates
| | - Zhaya Jaber Mohammed Al Marri
- Biosecurity Affairs Division, Development and Innovation Sector, Abu Dhabi Agriculture and Food Safety Authority, Abu Dhabi, United Arab Emirates
| | - Mohd Farouk Yuosf
- Biosecurity Affairs Division, Development and Innovation Sector, Abu Dhabi Agriculture and Food Safety Authority, Abu Dhabi, United Arab Emirates
| | - Asma Abdi Mohamed Shah
- Biosecurity Affairs Division, Development and Innovation Sector, Abu Dhabi Agriculture and Food Safety Authority, Abu Dhabi, United Arab Emirates
| | - Abdelmalik Ibrahim Khalafalla
- Biosecurity Affairs Division, Development and Innovation Sector, Abu Dhabi Agriculture and Food Safety Authority, Abu Dhabi, United Arab Emirates
| | - Hassan Zackaria Ali Ishag
- Biosecurity Affairs Division, Development and Innovation Sector, Abu Dhabi Agriculture and Food Safety Authority, Abu Dhabi, United Arab Emirates
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Rasmussen P, Shaw APM, Muñoz V, Bruce M, Torgerson PR. Estimating the burden of multiple endemic diseases and health conditions using Bayes’ Theorem: A conditional probability model applied to UK dairy cattle. Prev Vet Med 2022; 203:105617. [PMID: 35358837 PMCID: PMC9127345 DOI: 10.1016/j.prevetmed.2022.105617] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 03/14/2022] [Accepted: 03/16/2022] [Indexed: 11/18/2022]
Abstract
The Global Burden of Animal Diseases (GBADs) is an international collaboration aiming, in part, to measure and improve societal outcomes from livestock. One GBADs objective is to estimate the economic impact of endemic diseases in livestock. However, if individual disease impact estimates are linearly aggregated without consideration for associations among diseases, there is the potential to double count impacts, overestimating the total burden. Accordingly, the authors propose a method to adjust an array of individual disease impact estimates so that they may be aggregated without overlap. Using Bayes’ Theorem, conditional probabilities were derived from inter-disease odds ratios in the literature. These conditional probabilities were used to calculate the excess probability of disease among animals with associated conditions, or the probability of disease overlap given the odds of coinfection, which were then used to adjust disease impact estimates so that they may be aggregated. The aggregate impacts, or the yield, fertility, and mortality gaps due to disease, were then attributed and valued, generating disease-specific losses. The approach was illustrated using an example dairy cattle system with input values and supporting parameters from the UK, with 13 diseases and health conditions endemic to UK dairy cattle: cystic ovary, disease caused by gastrointestinal nematodes, displaced abomasum, dystocia, fasciolosis, lameness, mastitis, metritis, milk fever, neosporosis, paratuberculosis, retained placenta, and subclinical ketosis. The diseases and conditions modelled resulted in total adjusted losses of £ 404/cow/year, equivalent to herd-level losses of £ 60,000/year. Unadjusted aggregation methods suggested losses 14–61% greater. Although lameness was identified as the costliest condition (28% of total losses), variations in the prevalence of fasciolosis, neosporosis, and paratuberculosis (only a combined 22% of total losses) were nearly as impactful individually as variations in the prevalence of lameness. The results suggest that from a disease control policy perspective, the costliness of a disease may not always be the best indicator of the investment its control warrants; the costliness rankings varied across approaches and total losses were found to be surprisingly sensitive to variations in the prevalence of relatively uncostly diseases. This approach allows for disease impact estimates to be aggregated without double counting. It can be applied to any livestock system in any region with any set of endemic diseases, and can be updated as new prevalence, impact, and disease association data become available. This approach also provides researchers and policymakers an alternative tool to rank prevention priorities. Three approaches to impact aggregation for multiple endemic diseases explored. Flexible method proposed to avoid double counting impacts within a livestock system. Illustrated using 13 endemic diseases and health conditions in UK dairy cattle. Provides an alternative perspective on ranking disease prevention priorities.
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Affiliation(s)
| | - Alexandra P M Shaw
- Department of Livestock and One Health, University of Liverpool, Liverpool, United Kingdom
| | - Violeta Muñoz
- Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - Mieghan Bruce
- School of Veterinary Medicine, Centre for Biosecurity and One and Health, Murdoch University, Murdoch, Australia
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Blanco-Vázquez C, Alonso-Hearn M, Iglesias N, Vázquez P, Juste RA, Garrido JM, Balseiro A, Canive M, Amado J, Queipo MA, Iglesias T, Casais R. Use of ATP-Binding Cassette Subfamily A Member 13 (ABCA13) for Sensitive Detection of Focal Pathological Forms of Subclinical Bovine Paratuberculosis. Front Vet Sci 2022; 9:816135. [PMID: 35359676 PMCID: PMC8960928 DOI: 10.3389/fvets.2022.816135] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Accepted: 01/24/2022] [Indexed: 12/20/2022] Open
Abstract
Bovine paratuberculosis (PTB) is a chronic enteritis caused by Mycobacterium avium subspecies paratuberculosis (Map) that causes a heavy economic impact worldwide. Map infected animals can remain asymptomatic for years while transmitting the mycobacteria to other members of the herd. Therefore, accurate detection of subclinically infected animals is crucial for disease control. In a previous RNA-Seq study, we identified several mRNAs that were overexpressed in whole blood of cows with different PTB-associated histological lesions compared with control animals without detected lesions. The proteins encoded by two of these mRNAs, ATP binding cassette subfamily A member 13 (ABCA13) and Matrix Metallopeptidase 8 (MMP8) were significantly overexpressed in whole blood of animals with focal histological lesions, the most frequent pathological form in the subclinical stages of the disease. In the current study, the potential of sensitive early diagnostic tools of commercial ELISAs, based on the detection of these two biomarkers, was evaluated in serum samples of 704 Holstein Friesian cows (566 infected animals and 138 control animals from PTB-free farms). For this evaluation, infected animals were classified into three groups, according to the type of histological lesions present in their gut tissues: focal (n = 447), multifocal (n = 59), and diffuse (n = 60). The ELISA based on the detection of ABCA13 was successfully validated showing good discriminatory power between animals with focal lesions and control animals (sensitivity 82.99% and specificity 80.43%). Conversely, the MMP8-based ELISA showed a poor discriminatory power between the different histological groups and non-infected controls. The ABCA13-based ELISA showed a higher diagnostic value (0.822) than the IDEXX ELISA (0.517), the fecal bacterial isolation (0.523) and the real-time PCR (0.531) for the detection of animals with focal lesions. Overall, our results indicate that this ABCA13 ELISA greatly improves the identification of subclinically infected animals with focal lesions that are undetectable using current diagnostic methods.
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Affiliation(s)
- Cristina Blanco-Vázquez
- Centro de Biotecnología Animal, Servicio Regional de Investigación y Desarrollo Agroalimentario (SERIDA), Deva, Spain
| | - Marta Alonso-Hearn
- Department of Animal Health, NEIKER-Basque Institute for Agricultural Research and Development, Basque Research and Technology Alliance (BRTA), Derio, Spain
| | - Natalia Iglesias
- Centro de Biotecnología Animal, Servicio Regional de Investigación y Desarrollo Agroalimentario (SERIDA), Deva, Spain
| | - Patricia Vázquez
- Department of Animal Health, NEIKER-Basque Institute for Agricultural Research and Development, Basque Research and Technology Alliance (BRTA), Derio, Spain
| | - Ramón A. Juste
- Department of Animal Health, NEIKER-Basque Institute for Agricultural Research and Development, Basque Research and Technology Alliance (BRTA), Derio, Spain
| | - Joseba M. Garrido
- Department of Animal Health, NEIKER-Basque Institute for Agricultural Research and Development, Basque Research and Technology Alliance (BRTA), Derio, Spain
| | - Ana Balseiro
- Departamento de Sanidad Animal, Facultad de Veterinaria, Universidad de León, León, Spain
- Instituto de Ganadería de Montaña, Centro Superior de Investigaciones Científicas (CSIC-Universidad de León), León, Spain
| | - María Canive
- Department of Animal Health, NEIKER-Basque Institute for Agricultural Research and Development, Basque Research and Technology Alliance (BRTA), Derio, Spain
| | - Javier Amado
- Laboratorio Regional de Sanidad Animal del Principado de Asturias, Gijón, Spain
| | - Manuel A. Queipo
- Servicio de Sanidad y Producción Animal del Principado de Asturias, Oviedo, Spain
| | - Tania Iglesias
- Unidad de Consultoría Estadística, Servicios científico-técnicos, Universidad de Oviedo, Gijón, Spain
| | - Rosa Casais
- Centro de Biotecnología Animal, Servicio Regional de Investigación y Desarrollo Agroalimentario (SERIDA), Deva, Spain
- *Correspondence: Rosa Casais
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11
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Effective control of Johne’s disease in large Czech dairy herds. J Vet Res 2022; 66:61-67. [PMID: 35582488 PMCID: PMC8959688 DOI: 10.2478/jvetres-2022-0001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Accepted: 12/20/2021] [Indexed: 11/25/2022] Open
Abstract
Introduction Johne’s disease, caused by infection with Mycobacterium avium subsp. paratuberculosis (MAP), causes economic losses in dairy herds due to reduced milk production and premature culling. A test-and-cull strategy coupled with changes in calf rearing management preventing new infections has been introduced into infected herds to control MAP prevalence. This study appraised the effectiveness of these practice changes. Material and Methods In 19 large dairy herds (of a median 470 milk-producing cows), implementing MAP control measures for 3–7 years, a serum ELISA was used to detect infected cows in their dry-off period. The number of ELISA-positive animals per year (EPAY) was calculated and statistical analysis was used to test whether the EPAY total decreased during the control period and to analyse the EPAY in relationship to the duration of the control programme. Results Statistical support was found for a decrease of EPAY over time (P < 0.01, odds ratio 0.756) and in 14 herds a significant fall in the percentages of EPAY during the test period (P ≤ 0.05) was noted. Conclusion Our results demonstrated the effectiveness of the control measures in place to reduce MAP infection in herds with initial EPAY ≥3.36%. The missing decreasing trend in the remaining five herds with low average initial EPAY suggested the need for additional measures to reduce the number of infected animals in these herds.
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Atli MO, Hitit M, Özbek M, Köse M, Bozkaya F. Cell-Specific Expression Pattern of Toll-Like Receptors and Their Roles in Animal Reproduction. Handb Exp Pharmacol 2022; 276:65-93. [PMID: 35434748 DOI: 10.1007/164_2022_584] [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] [Indexed: 06/14/2023]
Abstract
Toll-like receptors (TLRs), a part of the innate immune system, have critical roles in protection against infections and involve in basic pathology and physiology. Secreted molecules from the body or pathogens could be a ligand for induction of the TLR system. There are many immune and non-immune types of cells that express at a least single TLR on their surface or cytoplasm. Those cells may be a player in a defense system or in the physiological regulation mechanisms. Reproductive tract and organs contain different types of cells that have essential functions such as hormone production, providing an environment for embryo/fetus, germ cell production, etc. Although lower parts of reproductive organs are in a relationship with outsider contaminants (bacteria, viruses, etc.), upper parts should be sterile to provide a healthy pregnancy and germ cell production. In those areas, TLRs bear controller or regulator roles. In this chapter, we will provide current information about physiological functions of TLR in the cells of the reproductive organs and tract, and especially about their roles in follicle selection, maturation, follicular atresia, ovulation, corpus luteum (CL) formation and regression, establishment and maintenance of pregnancy, sperm production, maturation, capacitation as well as the relationship between TLR polymorphism and reproduction in domestic animals. We will also discuss pathogen-associated molecular patterns (PAMPs)-induced TLRs that involve in reproductive inflammation/pathology.
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Affiliation(s)
- Mehmet Osman Atli
- Department of Reproduction, Faculty of Veterinary Medicine, Harran University, Şanlıurfa, Turkey.
| | - Mustafa Hitit
- Department of Genetics, Faculty of Veterinary Medicine, Kastamonu University, Kastamonu, Turkey
| | - Mehmet Özbek
- Department of Histology and Embryology, Faculty of Veterinary Medicine, Mehmet Akif Ersoy University, Burdur, Turkey
| | - Mehmet Köse
- Department of Obstetrics and Gynecology, Faculty of Veterinary Medicine, Dicle University, Diyarbakır, Turkey
| | - Faruk Bozkaya
- Department of Genetics, Faculty of Veterinary Medicine, Harran University, Sanlıurfa, Turkey
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Mõtus K, Rilanto T, Viidu DA, Orro T, Viltrop A. Seroprevalence of selected endemic infectious diseases in large-scale Estonian dairy herds and their associations with cow longevity and culling rates. Prev Vet Med 2021; 192:105389. [PMID: 34062370 DOI: 10.1016/j.prevetmed.2021.105389] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 05/12/2021] [Accepted: 05/20/2021] [Indexed: 01/17/2023]
Abstract
Herd culling rates and longevity represent herd health and welfare status as well as farm economic performance. The contribution of endemic circulation of the main cattle pathogens to herd performance has not been previously analysed. The aim of this study was to estimate the herd prevalence of selected endemic bovine pathogens among large commercial dairy herds and to analyse their associations with herd culling rates and longevity. Bulk tank milk (BTM) samples and 10 heifer serum samples were collected from 120 Estonian dairy herds with at least 100 cows, between August 2019 and July 2020. All samples were tested for antibodies against bovine herpesvirus 1 (BHV-1), bovine viral diarrhoea virus (BVDV), bovine respiratory syncytial virus (BRSV), Mycoplasma bovis, Mycobacterium avium spp. paratuberculosis (MAP) and Salmonella Dublin using commercial ELISA. Data on herd size, milk yield, culling rate (CR) and mean age of the culled cows (MAofCC) were collected from the Estonian Livestock Performance Recording Ltd. The apparent herd and animal prevalences were calculated, and linear regression models were used to identify associations between the herd status of six tested pathogens and CR and MAofCC. The herd seroprevalences for antibodies based on BTM and heifer serum sample testing were BHV-1 56.7 % (95 % CI 47.3; 65.7), Mycoplasma bovis 48.3 % (95 % CI 39.1; 57.6), MAP 2.5 % (95 % CI 0.5; 7.1) and S. Dublin 24.2 % (95 % CI 16.8; 32.8) in all tested herds. Excluding vaccinated herds, herds prevalence for BVDV was 27.0 % (95 % CI 19.0; 36.3) and for BRSV 94.7 % (95 % CI 88.1; 98.3). Herd seropositive status for BRSV was associated with lower MAofCC, and herds with BSRV-seropositive youngstock had increased CR. Herds with positive BTM test results for S. Dublin culled cows at an older average age (Coef = 3.79 months, 95 % CI 0.52; 7.07, p = 0.023). MAP-positive herds had somewhat lower herd MAofCC (Coef = -6.18 months, 95 % CI -12.98; 0.63, p = 0.075). There was also a tendency of BVDV-negative herds to have a lower CR than BVDV-positive herds (Coef = -3.03 %, 95 % CI -6.54; 0.49, p = 0.090), and vaccination against BVDV tended to be protective against high CR (Coef = -6.26 %, 95 % CI -12.61; 0.09, p = 0.053 compared to infected herds). This study shows that Estonian large-scale dairy herds are endemically infected with several important cattle pathogens. Most of the studied pathogens influence longevity and culling rates, thus entailing health and economic consequences.
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Affiliation(s)
- Kerli Mõtus
- Institute of Veterinary Medicine and Animal Sciences, Estonian University of Life Sciences, Kreutzwaldi 62, Tartu, 51006, Estonia.
| | - Triin Rilanto
- Institute of Veterinary Medicine and Animal Sciences, Estonian University of Life Sciences, Kreutzwaldi 62, Tartu, 51006, Estonia
| | - Dagni-Alice Viidu
- Institute of Veterinary Medicine and Animal Sciences, Estonian University of Life Sciences, Kreutzwaldi 62, Tartu, 51006, Estonia
| | - Toomas Orro
- Institute of Veterinary Medicine and Animal Sciences, Estonian University of Life Sciences, Kreutzwaldi 62, Tartu, 51006, Estonia
| | - Arvo Viltrop
- Institute of Veterinary Medicine and Animal Sciences, Estonian University of Life Sciences, Kreutzwaldi 62, Tartu, 51006, Estonia
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Villaamil FJ, Yus E, Benavides B, Allepuz A, Moya SJ, Casal J, Ortega C, Diéguez FJ. Factors Associated with the Introduction of Mycobacterium avium spp. Paratuberculosis (MAP) into Dairy Herds in Galicia (North-West Spain): The Perception of Experts. Animals (Basel) 2021; 11:ani11010166. [PMID: 33445689 PMCID: PMC7828141 DOI: 10.3390/ani11010166] [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: 12/02/2020] [Revised: 12/23/2020] [Accepted: 01/04/2021] [Indexed: 11/30/2022] Open
Abstract
Simple Summary Paratuberculosis remains one of the most important diseases of cattle worldwide. Control of disease is difficult and offers important challenges at both diagnostic and management levels. This paper describes a study aimed at quantification of expert opinion on risk factors for paratuberculosis infection in dairy herds in Spain. For this purpose, a panel of nine experts working in the field of paratuberculosis was selected. Risk factors were also included into a questionnaire that was responded to by 93 farms whose sanitary status was known. The most important risk factors for the introduction of MAP, according to expert opinions, were related to purchase and grazing practices. The scores obtained for each farm, based on the expert opinions, allowed MAP positive/MAP negative farms to be discriminated with 68.8% sensitivity and 68.7% specificity. Despite increased awareness of the disease and the fact that several countries are implementing control programs, there is still incomplete understanding of the epidemiology of the disease. This, together with the lack of completely reliable diagnostic methods, makes it of vital importance considering the inter-herd transmission factors in order to prevent the introduction of the disease. Prioritizing the most important factors should be useful for focusing future training initiatives and improving risk-reduction strategies in this economically important industry. Abstract This study aimed at quantifying expert opinions on the risk factors involved in Mycobacterium avium subsp. paratuberculosis (MAP) infection in dairy cattle herds. For this purpose, potential risk factors associated with the introduction of MAP into dairies were chosen based on a literature review and discussions with researchers and veterinarians. For each factor, a decision tree was developed, and key questions were included in each. Answers to these key questions led to different events within each decision tree. An expert opinion workshop was organized (following the recommendations of the OIE), and ordinal values ranging from 0 to 9 (i.e., a null to very high likelihood of infection) were assigned to each event. The potential risk factors were also incorporated into a structured questionnaire that was responded to by 93 farms where the sanitary status against MAP was known. Thereby, based on the values given by the experts and the information collected in the questionnaires, each farm was assigned a score based on their MAP entry risk. From these scores (contrast variable) and using a ROC curve, the cut-off that best discriminated MAP-positive and -negative farms was estimated. The most important risk factors for the introduction of MAP, according to expert opinions, involved purchase and grazing practices related to animals under six months of age. The scores obtained for each farm, also based on the expert opinions, allowed MAP positive/MAP negative farms to be discriminated with 68.8% sensitivity and 68.7% specificity. These data should be useful for focusing future training initiatives and improving risk-reduction strategies in the dairy industry.
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Affiliation(s)
| | - Eduardo Yus
- Institute of Food Analysis and Research, Santiago de Compostela University, 27002 Lugo, Spain;
| | - Bibiana Benavides
- Animal Health Department, Universidad de Nariño, San Juan de Pasto 52001, Colombia;
| | - Alberto Allepuz
- Department of Health and Animal Anatomy, Autonomous University of Barcelona, 08193 Barcelona, Spain; (A.A.); (S.J.M.); (J.C.)
- Centre de Recerca en Sanitat Animal (CReSA), UAB, IRTA, 08193 Barcelona, Spain
| | - Sebastián Jesús Moya
- Department of Health and Animal Anatomy, Autonomous University of Barcelona, 08193 Barcelona, Spain; (A.A.); (S.J.M.); (J.C.)
| | - Jordi Casal
- Department of Health and Animal Anatomy, Autonomous University of Barcelona, 08193 Barcelona, Spain; (A.A.); (S.J.M.); (J.C.)
- Centre de Recerca en Sanitat Animal (CReSA), UAB, IRTA, 08193 Barcelona, Spain
| | - Carmelo Ortega
- Animal Pathology Department, Veterinary Faculty, Zaragoza University, 50013 Zaragoza, Spain;
| | - Francisco Javier Diéguez
- Anatomy, Animal Production and Clinical Veterinary Sciences Department, Veterinary Faculty, Santiago de Compostela University, 27002 Lugo, Spain
- Correspondence: ; Tel.: +34-9828-22400
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