EFFECT OF THYROID FUNCTION ON REPRODUCTIVE PREFORMANCE OF BALADI GOATS WITH EMPHASIS on SUPER oVULATION RESPONSE AND EMBRYOS RECOVERY

This study aimed to investigate the effect of thy-roid function on reproductive performance in fe-male goats (does). Two experiments were carried outon 1] mature cyclic Baladi does. In the first Expenment, does were either kept as a control group (N=3) or drenched thiourea (50 mg/ kg oy weight/30 days) on day 7 of the synchron-Wed estrus to induce hypothyroidism (N=8). Es-'OUS activity was observed and blood samples “ rollected on days 0,15 and 30 after drenching thiourea as well as on day 7 after PGF2 injection. a trail was made with thyroxine supplementation for 30 days. in the second experiment, the above mentioned does were divided into 3 groups A control(N=3), hypothyrodism (N=4) and thyroxine treated hypothyrodism (N=4) groups. All groups were synchronized using progestrone impregnated intravaginal sponge for 18 days. Does were given PMSG at sponge removal and LH at heat and allowed to be mated. blood samples were collected on days 0,15 and 30 as well as on the days of heat of slaughtering ( day 5 after heat). thyroids, pitutary glands and genital organs were collected. numbers of CL and Graafian follicles were counted for evaluation of superovulation response. uterine horns were flushed with phosphate buffered saline and embryos were recovered. tissue samples were processed for histopathological examination. all blood samples were analyzed for thyroid hormones and progesterone (RIA) as well as for total lipid, cholesterol, triglycerides and glucose (colormetrically). results indicated that thiourea is strong goitrogenic agent in goats as indicated by marked reduction in T4 and T3 levels. Estrous activity was completely ceased in hypothyroidism group with  marked decreases in progesterone values and in-
creases in total lipid and cholesterol values. More- over, Superovulation response, ovulation rate and embryos recovery as well as progesterone, T4 and T3 values were obviously decreased in hypothyroidism group compared with the control group. Hypothyroidism caused obvious pathological changes in the studied endocrine glands as well as the genital organs. Following thyroxine therapy, estrous activity was not restored despite the improvement in thyroidfunction, lipid and glucose values. Also, the su-perovulation response, ovulation rate and em- bryos recovery as well as progesterone, T4 and the control group. On the other hand, thyroid size became within normal, ovary revealed increased number of growing follicles and somewhat healthy lutein cells and uterine glansd showed moderate secretory activity after the therapy. It was concluded that the normal function of the Thyroid gland is important for the reproductivefunction of goats. Hypothyroidism impaired ovar-ian function even after stimulation with superovu-lation treatment and it induced pathological le- sions in endocrine glands and genital organsThyroxine therapy should be applied for long pe-
riod to give satisfactory results in hypothyroidism.