Superovulation and Embryo Recoveries in Rathi (bos Indicus) Cattle: Effect of Equine Chorionic Gonadotropin or Porcine Fsh

The embryo recovery following superovulatory (SOV) treatment using equine chorionic gonadotrophin (eCG) and porcine follicular stimulating hormone (FSH) in native Rathi (Bos indicus) cattle was studied. In treatment I (n=33) 2000 IU of eCG was injected on day 8 of the natural estrus. In treatment II (n=17) donors received six 12 h im descending doses of porcine FSH (Super OV, Ausa International, USA) on day 8 to 10 of natural estrus. Animals were induced to estrus by PG injections followed by two inseminations 12 h apart at standing estrus and embryos were recovered by non-surgical means. The overall superovulatory response in the two treatments was 81.8 and 94.1 percent, respectively. Significant (P<0.01) differences were observed between the treatments for the superovulatory response and number of unfertilized ova (UFO) recovered. The results suggest that superovulation and embryo recoveries in native Rathi cattle are better with FSH than eCG. a Author for correspondence; 1 NRC on Camel, Jorbeer, Bikaner; 2 P.O. Tonk District, Rajasthan. INTRODUCTION Embryo transfer technology offers the chance to increase the overall rate of progress in genetic improvement, increase the productivity of a particular female and shorten the generation interval. The technology has been standardized and is in routine practice in many breeds of Bos Taurus cattle, but is yet to be standardized in various breeds of Bos indicus, having good adaptability in harsh tropical climate conditions. Rathi breed, native to the Thar desert in western Rajasthan, India is one of such breeds having excellent milk production potential. Superovulatory response and embryo recovery in cattle is highly breed specific (Breuel et al., 1991). Moreover, endocrine differences at the hypothalamo-pituitary gonadal level between Bos taurus and Bos indicus cattle (Randel and Mosby, 1977, Harrison et al., 1982, Randel, 1983)) may produce different effects on both the superovulatory response and embryo production (Bastidas and Randel, 1987). The present study was undertaken to study the results of superovulation and embryo recoveries in Rathi cattle using equine chorionic gonadotrophin (eCG) and porcine follicle stimulating hormone (FSH). MATERIAL AND METHODS The study was carried out at the Department of Veterinary Obstetrics and Gynaecology, College of Veterinary and Animal Science, Bikaner. Experimental animals Adult Rathi cows having calved at least once and with clinically normal ovaries and uterus were used as donors. Two estrus periods were observed prior to superovulatory treatment. The donors were stall fed with chaffed Sewan (Lasirus indicus) grass and concentrates. Superovulatory treatments In treatment I (n=33) donor cows were treated with a single i.m. injection of 2000 IU of eCG (Folligon, Intervet, Netherlands) on day Indian J. Anim. Res., 40 (2): 164 166, 2006