Vaccination to provide protection against Bovine Viral Diarrhoea (BVD) virus is vitally important despite good compliance with the current eradication programme.
The latest figures from Animal Health and Welfare Northern Ireland (AHWNI) reveal that the incidence of persistently infected calves being born on NI farms has reduced slowly since the programme became compulsory in 2016. The rolling annual prevalence of BVD has fallen slightly in June 2020 to 0.3% from a level of 0.35% for the same period in the previous year.
However, the overall incidence of BVD has reduced from 0.65% since the programme began. The total number of BVD Persistently Infected (PI) calves born in June this year exceeded 200.
Retained PIs are one of the greatest risks to the success of the eradication programme. There were 167 PI animals alive as of 1 st September. Many herd owners who have kept PIs have seen BVD infection persist into subsequent seasons, to their cost. It must be noted that despite PI removal, BVD virus can continue to circulate in the herd in subsequent years leading to disease therefore vaccination remains important to protect animals from the effects of infection.