Effect of prostaglandin analogue Cloprostenol on oestrus, ovulation and embryonic viability in sheep

Abstract

The effect of a single injection of 100 μg prostaglandin analogue Cloprostenol, during the luteal phase of the oestrous cycle was examined for synchronization of oestrus, time of ovulation and embryonic viability in ewes.Following injection of Cloprostenol alone, 84% of ewes were detected in oestrus 29–48 h later. Pretreatment with PMSG increased the proportion of ewes in oestrus within 36 h. In these ewes 38% had begun ovulating 30 h after the onset of oestrus and by 36 h 87% had begun ovulating. Normal embryos of 8-cells to blastocysts were obtained from ewes given PMSG and Cloprostenol, and on transfer to recipient ewes, treated with Cloprostenol, all recipient ewes produced lambs.It is concluded that injection of 100 μg Cloprostenol is an efficient method of synchronizing oestrus in ewes and that normal embryonic development would be expected in mated ewes following this treatment.