Neonatal diarrhea by bovine coronavirus (BCoV) in beef cattle herds

Bovine coronavirus (BCoV) is the second most important viral agent involved in neonatal diarrhea in calves worldwide. The reports on the frequency of BCoV infection in beef cattle herds under extensive management are uncommon in Brazil. The present study analyzed 93 diarrheic fecal samples of calves up to 60 days of age from 13 commercial beef cattle herds located in the states of Mato Grosso, Mato Grosso do Sul, Minas Gerais, Paran, and Rondonia. The fecal samples were collected during 2009-2012 and were previously analyzed for the presence of bovine rotavirus group A (BoRVA), with negative results. The presence of BCoV in the fecal samples was evaluated by the partial amplification of the N gene by using the semi-nested PCR technique. The expected products of 251 bp length were amplified 33.3% (31/93) of the analyzed diarrheic fecal samples. The results revealed that coronaviruses has important participation in the neonatal diarrhea complex of beef cattle herds reared extensively from the different geographical regions of Brazil.