Serological evaluation of precolostral Bovine Parainfluenza 3 Virus infection in an organised dairy herd

Calves are born agamaglobulinemic due to syndesmochorial placenta features that prevent immunoglobulin transfer to the foetus from the dam. The presence of precolostral antibody (ab) directly induces in-utero infection. The purpose of this study was to investigate Bovine Parainfluenza 3 virus (BPI3V) infection in precolostral calves and their dams. Samples were obtained from large-scale dairy cattle farm, which was established nearly 10 years ago. Blood serum samples were collected immediately after birth from precolostral calves (n=123) and their dams for about three-month period. Blood serum samples tested with Serum Neutralisation test using reference strain SF-4. BPI3V specific ab was found in 119 of 123 dams (96.7%), and ab titres showed a regular bell curve distribution’s and peak points were at 1/20 and 1/40 interval. Out of all precolostral calves, 31 (25.2%) were ab positive between 1/5 and 1/80 titer values. Average ab titre level was higher in the dams of ab positive calves as expected a result of recent infection history. The obtained data revealed that almost all the adults were exposed to BPI3V and one of the four pregnant had transplacental infections. Current veterinary practices are based on the prevention of diseases, which is an important point for intensive dairy breeding enterprises. Precolostral ab controls can be used as a convenient tool for estimating and eliminating the risks of upcoming postpartum infections.