A comparison of the effects on reproductive performance in sheep, of two methods of estimation of ovulation rate

Abstract

A comparison was made between the reproductive performance of ewes after either laparotorny, in which the uterus and ovaries were exteriorized, or laparoscopy, in which the uterus and ovaries were examined in situ through a telescopic instrument. There was no difference between ewes subject to laparoscopy and their unoperated flock mates. By contrast, in groups examined by laparotomy 10.2 per cent less ewes lambed per 100 ewes joined (P < 0.001). Ewes were most sensitive to laparotomy during the period 15-28 days after mating. There was no effect of laparotomy when the operation was performed before the ewe's first mating.