PREVALENCE OF BOVINE VIRAL DIARRHOEA VIRUS ANTIBODIES AND ANTIGEN AMONG THE ABORTED COWS IN INDUSTRIAL DAIRY CATTLE HERDS IN MASHHAD AREA OF IRAN

摘要

The measurement of antibody responses of animals exposed to BVDV either through a natural exposure or an immunization protocol is still a standard procedure. For BVDV, the test formats have been largely limited to ELISA which is a valuable diagnostic test to measure the level of BVDV specific antibodies as well as antigen in blood samples. In the present study, 120 blood samples were collected from the cows with the history of abortion in different period of pregnancy from different industrial dairy cattle herds of Mashhad area of Iran. Also 30 samples were collected from the cows with no history of abortion as control. The presence of antibody against BVDV from the 120 serum samples was investigated by indirect ELISA. From 120 serum samples which were collected from aborted cows, 89 samples were positive (%74.16). From these positive samples, 12 (13.48%), 54 (60.68%) and 23 (25.84%) samples belong to the first, second and third trimester of pregnancy, respectively. From 89 positive samples, 12 (13.48%) samples were related to stillbirth and 8 (8.99%) samples were belongs to the mummified fetus. From 89 positive samples, 71 (79.78%) were related to cattle between 2-5 years old and 18 (20.22%) were associated to cattle more than 5 years old. In control group, 20 samples (66.66%) were antibody positive. Also the presence of BVDV antigen in serum samples was investigated by Ag-capture ELISA. From 120 serum samples, 2 samples were positive (1.67%), which belongs to the second period of pregnancy. In control group, none of the samples were antigen positive. The results of this study showed that the prevalence of BVDV infection is high among the aborted cows of Mashhad area. Although this prevalence is higher than the control group, the observed difference is not significant.