Bovine coronavirus (BCV) infections in transported commingled beef cattle and sole-source ranch calves.
This study investigated bovine coronavirus (BCV) in both beef calves direct from the ranch and commingled, mixed-source calves obtained from an auction market. The level of BCV-neutralizing antibodies found in the calves varied among ranches in 2 different studies in a retained-ownership program (ROP), from the ranch to the feedlot. Calves with low levels of BCV-neutralizing antibodies (16 or less) were more likely to be treated for bovine respiratory disease (BRD) than those with higher titers. In 3 studies of commingled, mixed-source calves, BCV was recovered from calves at entry to the feedlot and the infections were cleared by day 8. The BCV was identified in lung samples [bronchoalveolar lavage (BAL) collection] as well as in nasal swabs. Calves with low levels of BCV-neutralizing antibodies at entry were most likely to be shedding BCV. Bovine coronavirus was isolated from both healthy and sick calves, but not from sick calves after 4 d arrival at the feedlot. Bovine coronavirus (BCV) should be considered along with other bovine respiratory viruses in the diagnosis of etiologies in bovine respiratory disease, especially for animals that become sick shortly after arrival. If approved vaccines are developed, it would be best to carry out vaccination programs before calves are weaned, giving them sufficient time to gain active immunity before commingling with other cattle.
Department of Veterinary Pathobiology, Oklahoma State University, Stillwater, Oklahoma 74078, USA. robert.fulton@okstate.edu
Robert W
RW
Fulton
Douglas L
DL
Step
Jackie
J
Wahrmund
Lurinda J
LJ
Burge
Mark E
ME
Payton
Billy J
BJ
Cook
Dirk
D
Burken
Chris J
CJ
Richards
Anthony W
AW
Confer
D000822:Animal Husbandry; D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D000998:Antiviral Agents / Q000627:therapeutic use; D048090:Bovine Respiratory Disease Complex / Q000097:blood / Q000188:drug therapy / Q000821:virology*; D001992:Bronchoalveolar Lavage Fluid / Q000821:virology; D002417:Cattle; D018352:Coronavirus Infections / Q000097:blood / Q000175:diagnosis / Q000188:drug therapy / Q000662:veterinary*; D017938:Coronavirus, Bovine / Q000276:immunology / Q000302:isolation & purification*; D009297:Nasal Mucosa / Q000821:virology; D014186:Transportation; D017201:Virus Shedding
D000914:Antibodies, Viral; D000998:Antiviral Agents