Effect of infection with bovine viral diarrhea virus alone, bovine rotavirus alone, or concurrent infection with both on enteric disease in gnotobiotic neonatal calves.
OBJECTIVE
To compare experimentally induced concurrent infection with bovine viral diarrhea virus (BVDV) and bovine rotavirus (BRV) with infection of either virus alone in calves.


METHODS
Seventeen 1-day-old gnotobiotic calves.


METHODS
Calves were allotted to 8 treatments as follows: group 1, mock-infected control calves (n = 2); group 2, inoculated with BVDV on day 1 (2); groups 3, 5, and 7, inoculated with BRV on days 1 (2), 4 (1), or 7 (2), respectively; and groups 4, 6, and 8, inoculated with BVDV on day 1 and with BRV on days 1 (2), 4 (2), or 7 (4), respectively. Concentrations of BVDV in serum and ileal tissues were measured, and BRV shedding in feces was determined. Histologic examination and immunohistochemical analysis were conducted to detect lesions and viral antigens.


RESULTS
Neonatal calves inoculated with BVDV alone or with BVDV on day 1 and BRV on day 7 developed villus atrophy and submucosal inflammation of the intestines. Concurrent BVDV and BRV infections acted synergistically in the intestinal tract, causing more severe enteric disease than infection with either virus alone. Severe lymphoid depletion was associated with BVDV infection in calves regardlesss of concurrent BRV infection.


CONCLUSIONS
Infection with BVDV played direct and indirect roles in enteritis in neonatal calves, causing villus atrophy in the duodenum and submucosal inflammation of the intestines. Also, BVDV potentiated effects of BRV. Concurrent infection with BVDV and BRV resulted in more severe enteric disease in neonatal calves than infection with BRV or BVDV alone.
Kelling
Clayton L
CL
Department of Veterinary and Biomedical Sciences, University of Nebraska, Lincoln 68583-0905, USA.
Steffen
David J
DJ
Cooper
Vickie L
VL
Higuchi
Deborrah S
DS
Eskridge
Kent M
KM
D000818:Animals; D000831:Animals, Newborn; D000914:Antibodies, Viral / Q000097:blood; D000956:Antigens, Viral / Q000378:metabolism; D001912:Bovine Virus Diarrhea-Mucosal Disease / Q000097:blood / Q000150:complications* / Q000821:virology; D002417:Cattle; D001908:Diarrhea Viruses, Bovine Viral / Q000472:pathogenicity; D004751:Enteritis / Q000473:pathology / Q000662:veterinary* / Q000821:virology; D005243:Feces / Q000821:virology; D007082:Ileum / Q000473:pathology / Q000821:virology; D007150:Immunohistochemistry / Q000662:veterinary; D012401:Rotavirus / Q000472:pathogenicity; D012400:Rotavirus Infections / Q000097:blood / Q000150:complications / Q000662:veterinary* / Q000821:virology; D013047:Specific Pathogen-Free Organisms
D000914:Antibodies, Viral; D000956:Antigens, Viral