CIDR PLUS OVSYNCH-BASED FIXED TIME AI PROTOCOL AS A THERAPEUTIC STRATEGY IN POST-PARTUM ANOESTRUS COWS

Résumé

The use of biotechnological advances in breeding and reproduction is a vital tool for enhancing the reproductive efficiency of cattle production. The study investigated the efficacy of a combined controlled-internal drug release (CIDR) and ovsynch synchronisation protocol with fixed-time artificial insemination (FTAI) as a therapeutic strategy for post-partum anoestrus in Bunaji cross-bred cows. Twenty-two apparently healthy cows (3-5 years old; 250-400 kg, previous calving history, 2-4 times) suffering from post-partum anoestrus (90-120 days) were randomly assigned into control and treated groups (n=11 each). The control group received 2ml of normal saline at time of hormonal treatments while the treatment group received an ovsynch regimen (Day 0: 100 g GnRH, Day 7: 500 g, PGF2 Day 9: 100 g GnRH) augmented by a progesterone releasing intravaginal insert (CIDR 1.38g progesterone) between days 0 and 7. FTAI was performed 16-24 h after the second GnRH administration. Blood sampling was performed at time of each treatment and AI. There was a significant increase in progesterone level in the treated group as compared with the control. Oestrus synchronisation rate and first service conception rate (90.90% and 80%) were significantly (P<0.05) higher than control group (18.18% and 50%). It was concluded that the CIDR plus ovsynch based FTAI protocol is an effective management strategy for enhancing fertility in post-partum anoestrus Bunaji cross-bred cows.