Effect of dietary energy on the superovulatory response to PMSG treatment, with special reference to embryo quality, metabolic and endocrine response in female goats

ABSTRACT

Thirty Baladi non lactating, goats were randomly allocated according to their dietary treatments into 3 groups. Group I [Restricted diet], group II [Flushing diet] and group III [High fat diet]. The oestrous cycle were synchronized with progestagen impregnated intravaginal sponges [MPA], for 14 days, followed by injection of PMSG at day 13, and HCG at day 14, for all female goates. At day 5-6 post oestrus, the embryos/ova were recovered surgically and examined for evaluation. The onset and duration of oestrus varied significantly between the groups. It appeared earlier in animals in group II and III than in group I. The total ovarian response, increased in group III and decreased in group II, compared with group I. However, the average number of normal corpora lutea was non significantly affected by feeding regimens. The data also revealed that, the total percentage of transferable embryos [grades 1, 2 and 3] was significantly elevated in groups II and III, compared with group I. Similarly the recovery rate was higher in groups II and III. At day of embryo recovery, the concentrations of serum progesterone have remarkable increase in groups II and III. In addition, the level of estradiol-17beta recorded a peak level at the day of oestrus. This level dropped to record a lowest values at day of embryo recovery. Serum triglycerides, cholesterol and HDL-CH were lowered in feed restricted diet compared with high fat level. Regarding serum insulin concentration, goats received the energy restricted diet had a significant decrease in serum insulin level than those received flushing or high fat diets. It is concluded that the level of dietary energy had a significant effect on the onset and duration of oestrus, ovarian activity and quality of embryos available for transfer, but increased the number of unovulatory follicles