A Survey of Southern Arizona Calves for Persistent Infection with Bovine Viral Diarrhea Virus
Keywords:bovine viral diarrhea virus, BVD, persistent infection, PI
This study was conducted to determine the prevalence of persistent infection (PI) with bovine viral diarrhea virus (BVDV) in dairy and beef calves in southern Arizona. Formalin fixed skin biopsies of ear from the animals were used to perform immunohistochemistry (IHC). A total of 3,010 dairy bull calves, ranging in age from one day to approximately 14 days, were sampled and 15 PI calves were identified, giving an apparent prevalence of 0.49%. Range beef calves ranging from newborn to approximately 12 months were also sampled. One PI animal was identified out of 1,096 calves tested. Dairy calves testing positive for BVDV at the first sampling were retested using IHC and virus isolation at two-week intervals to confirm PI status.