Bovine Pestivirus Infection: a Cause of Ovulatory Disturbance in Dairy Cows

Twelve (Experiment I) and four (Experiment II) multiparous dairy cows seronegative to pestivirus were selected and randomly assigned to either a control group which did not become infected or a treatment group in which all cows became infected following intranasal inoculation ۹ days before AI. The experimental induction of infection was carried out with ۲ ml of non-cytopathic pestivirus (BVD virus) suspension containing ۵ log۱۰ TCID۵۰/ml (Experiment I) and ۴.۵ log۱۰ TCID۵۰/ml (Experiment II). In both experiments, the cows were superovulated on day ۱۰±۲ of the cycle using the standard procedures. The cows in Experiment I were artificially inseminated at ۱۲ and ۲۴ h after the onset of estrus and a non-surgical ova/embryo collection was performed ۷ days after AI. In Experiment II, the cows were slaughtered on day ۸ after superovulation-induced estrus and the ovaries submitted for gross and histopahological examination including immunohistochemistry. Mean (±SE) number of ovulatory sized follicles on day of AI and corpora lutea palpated on day ۷ after AI were significantly (p

کلیدواژه ها:

pestivirus infection ، superovulation ، immunohistochemistry ، OVARY ، dairy cows