EFFECT OF THE BOVINE VIRAL DIARRHEA (BVD) VIRUS ON PRE-IMPLANTATION BOVINE EMBRYOS - PRELIMINARY-STUDY

Five crossbred-Holstein cows, approximately three to seven years of age, were superovulated using pregnant mare's serum gonadotropin (PMSG) and prostaglandin F2α (Prostin F2α). At the induced estrus, each cow was artificially inseminated with frozen semen. Seven days after insemination, the lumen of the right uterine horn of each cow was inoculated with BVD virus in Eagle's minimum essential tissue culture medium, and the lumen of the left horn was infused with tissue culture medium only. Three days later, each cow was subjected to midventral laparotomy under general anesthesia and embryos were collected. A total of 22 embryos were recovered; 12 were from infected uterine horns and ten were from non-infected uterine horns. All embryos from the non-infected uterine horns were in the late blastocyst stage without the zona pellucida. Of the embryos collected from the infected uterine horns, eight of 12 (66.6%) still possessed zona pellucida and appeared in a degenerative state. The remaining four embryos were morphologically similar to those from the non-infected uterine horns. Electron microscopic examination of the degenerated embryos from the infected uterine horns demonstrated the presence of a structure which morphologically resembled the BVD virus. The results of this preliminary study indicate that the BVD virus within the uterine horns may interfere with normal development of preimplantation bovine embryos. Therefore, it is proposed that the BVD virus could adversely affect early stages of gestation in the cow, resulting in infertility. © 1979 Geron-X, Inc.