Methodology of Using eCG or FSH Regimens for Multiple Ovulations and Embryo Recovery by Assisted Reproductive Technologies in Sheep

Abstract

This study aimed to profit the assisted reproductive technologies in sheep presented two techniques for multiple ovulations and embryo recovery. Multiparous ewes of Egyptian Barki (N=15) and Australian Dorper (N=20) were used in the first and second techniques, respectively. Technique I was performed in Faculty of Veterinary Medicine, Sadat city, Menufia province, Egypt during the period from August to February, while technique II in Werribee, Victoria, Melbourne City Australia during the period from March to April. The technique I (20-21 days) based on using intravaginal progesterone (P 4 )-sponges for fourteen days, equine chorionic gonadotropin and flushing of embryos under local anesthesia 5 days after mating. However, the technique II (18 days) based on using intravaginal P 4 -controlled internal drug release silicon devices for twelve days with six injections of the follicle-stimulating hormone (Folltropin; FSH), eCG and surgical flushing of embryos under general anesthesia four days after laparoscopic intrauterine insemination. The recovery rate of the harvested morulae and blastocysts in relation to the developed corpora lutea were 38.2 and 24.4 % in the technique I, respectively, while they were 40.8 and 25.8 % in the technique II, respectively. Moreover, the percent of unfertilized oocytes and lost recovered structures, those of early embryonic death absorbed or lost during flushing in the technique I were 18.2 and 31.6 %, respectively, while they were 7.3 and 13.7 % in the technique II, respectively. In conclusion, the two presented techniques showed variable results of recovered embryos, but the harvested embryos produced by ewes younger than 6 years old were higher than 38 %.