Lightfoot, R.J., Croker, K.P. & Marshall, R., 1976. Use of a prostaglandin analogue (ICI 80996) for the synchronization of oestrous and lambing in Merino ewes. Proc. Int. Sheep Breeding Congr. (Muresk). pp. 449-454.
ICAR-Central Sheep & Wool Research Institute, Avikanagar, Rajasthan, India has developed a very economic progestogen-impregnated intravaginal sponge, Avikesil-S for estrus induction and synchronization in sheep and goats. The sponge is being used in sheep and goat farms belonging to various government animal science research institutes, universities, state animal husbandry departments, NGOs, entrepreneurs, small farmers pan India with very good success rate in estrus synchronization and induction. In various experiments conducted our sheep and goat farms, we have observed more than 90% success rate in estrus induction and synchronization, while more than 60% estrus induction rate in anestrus sheep and goat. The details of sponge can be obtained from institute's website.