Dynamics of natural bovine herpesvirus-1 (BoHV-1) infection in a dairy herd.
In this study, natural cycling of BoHV-1 infection was investigated in two groups of dairy cattle containing 2120 head. Group 1 comprised 127 animals and they were monitored for BoHV-1 infection virologically and serologically in six consecutive sampling periods. It consisted of naive heifers between 6 and 8 months of age, while in group 2, age, sex and the BoHV-1 serostatus of the animals were disregarded. The animals in group 1 were found to have seroconverted at the second sampling. Results of the serological study showed slight antibody response after natural BoHV-1 infection in the herd and neutralizing titres fell below protective levels in the 6-8 months after the peak. During the 2-year study period, one recurrence was detected after primary infection. Virus isolation studies revealed a cytopathic effect indicative of BoHV-1 in two nasal swabs taken during the fifth sampling period from animals with mild upper respiratory tract symptoms. As the study was carried out under natural conditions, it is not known whether the viruses isolated were from recurrences or re-infections. Data from cross-neutralization tests with herd isolates showed higher antibody response than those with the reference virus. The dynamics of BoHV-1 in both groups were found to be statistically similar.
Gungor
A Burak
AB
Uludag University, Faculty of Veterinary Medicine, Department of Microbiology, Bursa, Turkey.
Ozkul
A
A
D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D002417:Cattle; D004279:DNA, Viral / Q000737:chemistry / Q000235:genetics; D003612:Dairying; D004196:Disease Outbreaks / Q000662:veterinary*; D005260:Female; D007242:Herpesvirus 1, Bovine / Q000235:genetics / Q000302:isolation & purification*; D007241:Infectious Bovine Rhinotracheitis / Q000453:epidemiology* / Q000821:virology*; D008137:Longitudinal Studies; D008297:Male; D009500:Neutralization Tests; D016133:Polymerase Chain Reaction / Q000662:veterinary; D016036:Seroepidemiologic Studies
D000914:Antibodies, Viral; D004279:DNA, Viral