A new technique for nonsurgical embryo recovery in superovulated ewes treated with estradiol and oxytocin

Abstract

The development of an efficient and practicable method for transcervical collection of embryos in Awassi ewes to the improvement of embryo recovery was investigated. Twenty-four non-pregnant Awassi ewes of 3-4 years of age were randomly allocated into two groups (n = 12). Each ewe was treated with a progesterone impregnated intra-vaginal sponge for 12 days. The following superovulation treatment was used: ewes received 1200 IU of eCG once as an intramuscular injection 48 h prior to sponge withdrawal. Ovarian response was assessed by determining the number of corpora lutea by laparoscopy at day 6 after mating. Ewes of group 1 (n = 12) their embryos were recovered using semi-laparoscopic technique. Ewes of group 2 (n = 12) their embryos were recovered using transcervical technique. All ewes of this group on the evening of day 5 post inseminations, received an i.m. injection of estradiol 17β 2 mg, 12h later, an i.v. injection of 10 IU of oxytocin. A bovine teat dilator introduced into cervical canal and gradually dilated in order to dilate and open the cervical canal with a help of screw provided with the instrument. Results of the present study showed that there was no significant difference in the number of recovered embryos in superovulated ewes when animals treated with estradiol and oxytocin with transcervical technique and semi-laparoscopic technique. It was possible to pass the catheter through the cervix by aid of bovine teat dilator enhanced by estradiol and oxytocin treatment. In conclusion, the technique for transcervical collection of embryo from ewes, as described in the present study, may give new encouragement to embryo transfer programs in this species. Key words: Superovulation. Transcervical embryo recovery. semi-laparoscopic technique. Estradiol. Oxytocin. Awassi ewes