Prevalence of Infectious Diseases on Dairy Farms Classified on The Basis of Their Biosecurity Score.

ABSTRACT

Introduction: The aim of the study was to investigate the relationship between biosecurity as scored on the Italian National Animal Welfare Reference Centre (Centro di Referenza Nazionale per il Benessere Animale - CReNBA) checklist and the prevalence of Mycobacterium avium subsp. paratuberculosis, Chlamydophila abortus and Neospora caninum on dairy farms located in Ragusa, Italy. Material and Methods: The checklist was used to assign an animal welfare score to 31 dairy farms. Twenty-one farms with a moderate score (>33%, <66%) formed group 1, and 10 farms with a high score (>66%) were group 2. Blood samples were collected from all cows on each farm to investigate the titres of antibodies against the relevant pathogens. Two-way analysis of variance was applied to assess differences between the two experimental groups and the Mann-Whitney test was applied to evaluate prevalence differences in the tested parasites between the groups. Results: All tested farms had a score that classified them as either good or excellent. A higher incidence of Neospora caninum was observed in group 1. The incidences of the other two parasites were no different between the two groups. Conclusion: The CReNBA checklist represents an impartial, reproducible, functional and smart instrument based on risk analysis and assigns a farm a mathematical animal welfare score. Among the parasites tested for, only Neospora caninum had prevalence influenced by biosecurity. Our preliminary results highlighted the positive associations between good animal welfare, high levels of biosecurity, and the prevention of the infectious diseases caused by the parasites in our focus, which are common on dairy farms.