Preparation for genetic improvement of breeds through the comparative study of the effects of two heat induction methods (vaginal sponges and PMSG): the case of the Sahel goat in Niger.

Abstract

In Niger, goats are in first place with 36% of the livestock. In spite of this position, a decrease in fertility from 123.2% to 83.62% and in fertility from 87.07% to 65.02% was observed in 1998. Therefore, in order to increase the reproductive capacity of goats, we compared the effects of two hormonal methods of heat induction and synchronization in the Sahelian goat during the off-season in the urban commune of Tillabéri. The herd is composed of eight goats of different ages separated into two batches of 4 goats each. Two multiparous goats and two kids make up each batch.v Batch 1 animals received a vaginal sponge treatment followed by an injection of PMSG while batch 2 animals received two injections of PMSG at a dose of 0.5 ml each at 11 day intervals. An aproned billy goat was used for heat detection.  At 23 hours after removal of the vaginal sponges, 75% of the goats in batch 1 came into heat, whereas in batch 2 it took 3 days for 50% of the goats to respond favourably. Parity and age influenced heat induction (p= 0.001). Multiparous goats responded quite favourably and quite quickly to hormone treatments for heat induction and synchronization than primiparous goats. Now the question we are going to ask ourselves is whether we will get the same results with a treatment based exclusively on vaginal sponge.

Key words: Induction, heat, Sahelian goat, synchronisation, vaginal sponge, PMSG