Incorporation of CIDR into Ovsynch Protocol Improved the Reproductive Performance of Anestrous Buffaloes During Low Breeding Season

A study was conducted to determine the effectiveness of CIDR (Controlled Internal Drug Release) in Ovsynch protocol for the treatment of anestrus in buffaloes during low breeding season (April to June).Buffaloes in Group T1 (Ovsynch, n=25) received GnRH on a random day (d0), PGF 2α on d7, GnRH on d9, followed by fixed timed artificial insemination (FTAI) at 16-20 hours after second GnRH.Buffaloes in Group T2 (CIDR-synch, n=30) were treated as in group T1 except that a CIDR containing 1.9 gm progesterone was inserted into the vagina on d0 and removed on d7.Ovarian cyclicity status during CIDR insertion and the presence of corpus luteum (CL) on 8-9 day after FTAI were determined using transrectal ultrasonography.Estrus expression rate (96.7% vs 68%; P=0.008) and ovulation rate (93.3% vs 76%; P=0.10) were higher in CIDR-synch than in Ovsynch group.Although pregnancy rate from FTAI did not differ between CIDR-synch (33.3%) and Ovsynch group (16%), overall pregnancy rate obtained from FTAI plus natural breeding within one month after FTAI was higher (P=0.04) in CIDR-synch (46.7%) than in Ovsynch group (20%).Pregnancy outcome from FTAI in both treatment groups was not affected by the ovarian cyclicity status at the initiation of the protocol.In conclusion, incorporation of CIDR into Ovsynch protocol improved the reproductive performance of anestrous buffaloes during low breeding season.