Our objective was to compare the effect of treatment with GnRH at first (G1) Breeding-Ovsynch portion a Double-Ovsynch (DO) protocol human chorionic gonadotropin (hCG) on pregnancies per artificial insemination (P/AI) in lactating dairy cows. In experiment 1, cows (n = 1,932) submitted DO for timed (TAI) 2 commercial farms were blocked by parity (primiparous vs. multiparous) and randomly assign...

A cross-sectional study was conducted from January to July 2021 determine the prevalence and contributing factors repeat breeding (RB) postpartum anestrus (PPA) in crossbred dairy cattle central highland of Ethiopia. Furthermore; a retrospective used collect data on occurrence RB PPA associated risk factors. The pregnancy rate determined by rectal palpation day 60 after hormonal therapy using d...

Beef cows (n = 473) from two locations were stratified by breed, postpartum interval, age, and AI sire and were randomly allotted to one of four treatments for synchronization of ovulation. Ovulation synchronization protocols included the Ovsynch protocol with (n = 114) or without (n = 123) 48-h calf removal from d 7 to 9 (d 0 = 1st GnRH injection) or the COSynch protocol with (n = 119) or with...

The study was undertaken to compare the efficacy of an estradiol-17β + CIDR based protocol with the conventional ovsynch + CIDR based protocol for synchrony of wave emergence and ovulation in Murrah buffalos. In group I (n=25), on day 0 (beginning of experiment), buffaloes were administered a CIDR device (1.38 g P4) and concurrently received 1.5 mg E-17β. On day 9, the CIDR was removed and a pr...

Development of methods to manipulate the estrous cycle so that all cows are in estrus during a short, predefined period (synchronized estrus) while maintaining normal fertility has been a difficult goal to achieve, but has resulted in the creation of valuable synchronization protocols that are available to producers today. Although implementation of estrus synchronization and AI will improve th...

The present study was performed to determine the effect of PGF2α and GnRH injections in different time intervals on fertility in Hair goats during breeding season. Totally, 80 primiparous Hair goats were divided into four groups (n=20 in each) according to the body condition scores of the animals. The animals in groups were treated as follows; first group (Ovsynch), GnRH on day 0, PGF2α on day ...

The objective of this study was to compare the effects of three different estrus synchronization protocols on the pregnancy rates of lactating dairy cows. Group 1 (Ovsynch protocol; n= ) animals received 20 μg GnRH on day 0, 500 μg PGF2α on day 7 and 20 μg GnRH on day 9; Group 2 (Heatsynch protocol; n= ) received 20 μg GnRH on day 0, 500 μg PGF2α on day 7 and an injection of 1 ml estradiol cypi...

Important developments have occurred in the last two decades, since the advent of the Ovsynch protocol, on the understanding and use of synchronisation programmes for management of reproduction in dairy herds. This better understanding of oestrus cycle control associated with suboptimal reproductive performance in dairy herds has led dairy producers to quickly adopt timed artificial inseminatio...