Relative associations of cattle movements, local spread, and biosecurity with bovine viral diarrhoea virus (BVDV) seropositivity in beef and dairy herds
The success of bovine viral diarrhoea virus (BVDV) eradication campaigns can be under-mined by spread through local transmission pathways and poor farmer compliance withbiosecurity recommendations. This work combines recent survey data with cattle move-ment data to explore the issues likely to impact on the success of BVDV control in Scotland.In this analysis, data from 249 beef suckler herds and 185 dairy herds in Scotland were stud-ied retrospectively to determine the relative influence of cattle movements, local spread,and biosecurity on BVDV seropositivity. Multivariable logistic regression models revealedthat cattle movement risk factors had approximately 3 times greater explanatory powerthan risk factors for local spread amongst beef suckler herds, but approximately the sameexplanatory power as risk factors for local spread amongst dairy herds. These findings aremost likely related to differences in cattle husbandry practices and suggest that wherefinancial prioritization is required, focusing on reducing movement-based risk is likely tobe of greatest benefit when applied to beef suckler herds. The reported use of biosecuritymeasures such as purchasing cattle from BVDV accredited herds only, performing diag-nostic screening at the time of sale, implementing isolation periods for purchased cattle,and installing double fencing on shared field boundaries had minimal impact on the risk ofbeef or dairy herds being seropositive for BVDV. Only 28% of beef farmers and 24% of dairyfarmers with seropositive herds recognized that their cattle were affected by BVDV andthose that did perceive a problem were no less likely to sell animals as replacement breed-ing stock and no more likely to implement biosecurity measures against local spread thanfarmers with no perceived problems. In relation to the current legislative framework forBVDV control in Scotland, these findings emphasize the importance of requiring infectedherds take appropriate biosecurity measures to prevent further disease transmission andconducting adequate follow-up to ensure that biosecurity measures are being implementedcorrectly in the field.© 2013 Elsevier B.V. All rights reserved.
Journal Title/Title of Proceedings
Preventive Veterinary Medicine