Study on duration of maternal antibodies in calves against Bovine Herpes virus type 1 (BHV-1)

In order to estimate the mean of maternal antibody in calves against BHV-1 (Bovine Herpes virus type 1), this study was carried out in a population of calves from non-vaccinated dairy cattle at 2 livestock in Qazvin province. One hundred thirteen sera out of 512 were collected from 1-4 months unvaccinated calves. We used Blocking –Percentage of maternal antibodies against BHV-1, which obtained by Blocking ELISA assay in 1-4 months calves sera. The result of one way analysis of variance determined that there was a significant difference among blocking percentage of maternal antibodies against BHV-1 in 1-4 months (P<0.001). Comparing percentage of mean titer indicated a decreasing trend with respect to age i.e. from 84.4(a 95% CI: 78.1- 90.6) in 1 month to 57.6(a 95% CI: 47.1- 68.2) in 4 months, which was near to 55 as cut off point. Tukey's method showed a significant difference between the Blocking percent of mean titer between 1 and 4(P<0.001), 2 and 4 (P=0.034) months. Chi-square test for independency showed a significant association between age and seroactivity (P=0.005).