Neurological signs in lambs as indication for BVDV circulation in a cattle young stock rearing herd

Abstract

AbstractTwin lambs, born on a farm where cattle young stock and sheep were raised together in the same barn, presented with neurological signs. As border disease could not be ruled out, samples were sent for diagnostic testing and subsequent sequence comparison to identify potential infection with sheep or cattle pestiviruses. The 5′UTR polymerase chain reaction (PCR) confirmed that both lambs and one calf were infected with a bovine viral diarrhoea virus (BVDV) 1b strain. Additional analysis of the E2 and NS5b PCR products demonstrated a ∼100% sequence identity for 5′UTR, E2, and NS5b. Viral transmission from a persistently infected (PI) calf to the sheep dam during pregnancy was considered the most likely route of infection. In spite of the advice to separate and slaughter the lambs, as they could act as a source of infection to the rest of the sheep and cattle, they remained in the flock. Over time they overcame the clinical signs and were slaughtered at the end of the season. This case demonstrates that sheep can be infected with BVDV. Neurological signs and other health problems in sheep could indicate a BVDV infection in both sheep and cattle when reared in close contact.