Gonadotropin extraction from pregnant mares' serum and effect of PMSG preparation on the fertility of Mongolian native ewes

• Published in: Small ruminant research Vol. 28; no. 1; pp. 61 - 66
• Main Authors: Donrov, Ts, Batsaihan, D, Ley, W.B
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 1998
• Subjects: eCG; Estrous induction; estrus; estrus synchronization; ewes; extraction; Fertility; follicle-stimulating hormone; khalkh; lambing rate; luteinizing hormone; Mongolian ewe; Mongolian PMSG; natural mating; pms; pregnant mare serum gonadotropin; purification; ratios; sheep breeds; synchronized females; eCG; Mongolian PMSG; Fertility; Estrous induction; Mongolian ewe
• ISSN: 0921-4488; 1879-0941
• DOI: 10.1016/S0921-4488(97)00064-3

Pregnant mares' serum (PMS) was prepared from blood collected from native Mongolian mares between 60 and 70 days of gestation. Pregnant mares' serum gonadotropin (PMSG; potency of 400 IU/mg) was extracted from PMS by precipitation in graded concentrations of ethanol in a stepwise fashion. The equivalent of 600 IU PMSG as native PMS was administered to Mongolian ewes (group A;
n=106) at 7-day intervals for a treatment period of 21 days to induce estrous. The same was accomplished in 60 ewes (group B) using 600 IU PMSG extract. A third group of ewes (group C;
n=123) served as untreated controls during the same time period. Onset of estrous was assessed by daily introduction of vasectomized rams. Ewes determined in estrous were bred by natural service during the subsequent 12 h by one of several fertile rams. Each ewe was allowed exposure to fertile rams only once for the duration of this trial. Estrous was detected in 65.1%, 71.7% and 26.1%, respectively, in groups A, B and C, by the end of the second week of the trial. Groups A and B were not different, but group C had fewer (
P<0.01) ewes detected in estrous by this same time period in comparison to either group A or B. Overall, there were no differences between groups A and B, for the number of ewes detected in estrus, number of ewes bred and number of bred ewes that lambed. Group C had fewer (
P<0.01) ewes in each of these reproductive performance parameters when compared to either group A or B.