The effect of hCG given on day 12 post-mating on ovarian function and embryo survival in Beetal goats in southern Punjab, Pakistan

Authors: MUSHTAQ H. LASHARI, ZAHIDA TASAWAR

Abstract: The present study was conducted to determine the effects of human chorionic gonadotrophin on ovarian function and embryo development of Beetal goats reared under traditional conditions at the Sheep and Goat Research Station, Bahauddin Zakariya University, Multan. Fourteen Beetal goats at 4 years of age, weighing 40 ± 0.41 kg (mean ± SEM) were used. Their daily food was hay, green fodder, tree loppings, and 250 g of additional rations per goat. These goats were mated to buck at synchronized estrus by 2 i/m injections of dalmazin, given at 11-day intervals. These animals were divided into 2 equal groups (7/group) through random stratification by body weight. These were given either saline (Group I) or 300 IU human chorionic gonadotrophin (Group II) on day 12 post-mating. The blood samples were collected for progesterone. The animals were slaughtered on day 25 of pregnancy. Reproductive tracts were removed, corpora lutea, isolated, counted, and weighed. Embryos were also recovered, weighed, and measured for crown rump length, amniotic sac length, and the width and number of caruncles forming placentomes were counted as well. The results showed that human chorionic gonadotrophin increases the plasma progesterone concentration (P < 0.05). Treatment with hCG not only improves the conceptus growth but also increases the number of caruncles significantly (P < 0.05). In conclusion, the results of the present study revealed that treatment with human chorionic gonadotrophin may be luteotrophic and embryotrophic. The embryonic mortality was 27% in this breed. The reduction in embryo mortality was found after being given human chorionic gonadotrophin (17%), and thereby could improve embryo survival and increase litter size.

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