We determined the prevalence of antibodies to infectious bovine rhinotrache
itis virus (IBRV) and bovine viral diarrhea virus (BVDV) in sera of dairy c
ows on 4 different farms in the Republic of Croatia. A high percentage (60.
8%) of cows had various reproductive disorders. The results showed that ser
oprevalence of infectious bovine rhinotracheitis (IBR) was 85.8% and that o
f bovine viral diarrhea (BVD) was 79.2% in tested cows. Antibodies to both
viruses were found in 80.8% of cows with reproductive disorders but in only
46.8% of cows without reproductive disorders. This difference was statisti
cally significant (P<0.01), and indicated a connection between reproductive
disorders and simultaneous infections with IBR and BVD viruses in dairy co
ws. (C) 1999 by Elsevier Science Inc.