Effect of GnRH on conception rate following AI in cattle - Gonadotropins for conception improvement in cattle

In all, 346 animals comprising of 167 (J) and 179 (J X RS) cows were inseminated artificially at livestock farm of CSKHPKV, Palampur. Buserelin acetate and Gonadorelin were injected through i/m route for the treatment as GnRH analogues. Depending upon the groups, either single or double inseminations (24 hours after the first AI). Among the Jersey cows 59.6 and 53.8 percent animals conceived, following GnRH administration and 40.0 and 45.0 percent conceived in control group following single or double AI, respectively. Similarly, among crossbred cows, 58.2 and 55.5 percent animals conceived when inseminated along with GnRH and 45.0 and 60.0 percent conceived in control groups following single and double AI, respectively. It was concluded that both the preparations were almost equally effective. In Jersey cows either of the two routes (I/M or I/V) of administration of hormone could be adopted but in crossbred cows only I/M route should be preferred. Also, if GnRH is to be injected along with AI in normal animals, single insemination is sufficient. In case no hormone is to be injected, double insemination at 24 hr. interval is advantageous.