Effects of GnRH on Conception Rate at the Time of Artificial Insemination in Crossbred Dairy Cows

Abstract

The present study was conducted to investigate the influence of GnRH (Gonadotropin Releasing Hormone) administration on conception rate at the time of artificial insemination (AI) in healthy crossbred dairy cows. A total 90 cows were recruited and a preset questionnaire was answered by the owners. The cows were divided randomly in to two equal groups. GnRH treated group was injected intramuscularly (i/m) in the neck muscle with GnRH (Gonadorelin Acetate) at the time of AI. Again the treated group was divided randomly into three equal groups (15 cows each) for three different doses of GnRH (200, 250, 300 µg). The necessary information was taken from the owner with pretested questionnaire. The overall 71.11% conception rate was found in GnRH treated group on the other hands 55.56% conception rate was in control groups and having significant effect (P<0.05). There were significant effect (P<0.05) of age and milk yield and there were no significant effect of doses, timing, body condition score and parity within GnRH treated group. The study revealed that use of GnRH improved the conception rate in crossbred dairy cows at the time of AI.