【摘要】 <正> 重复超数排卵处理是家畜胚胎移植中提高供体母畜利用率的重要措施。据报道,使用同一种促性腺激素重复处理会引起兔(Manrer等,1968;Reel等,1976)、绵羊(Paulsson,1962)青年牛(Howe等,1962)和母牛(Turman等,1977;Turman和Wetteman,1978)等超数排卵反应的下降。认为这种现象是由于形成外源促性腺激素抗体所发生的抗药性所致(Willett等1953;Juinudeen等,1966;Onuma等,1969)。但也有些研究并未证实使用同一种促性腺激素重复处理牛(Dziuk等1958;Scanlon,1972)或羊(Gordon,1975)会造成其卵巢反应的下降。本试验的目的是观察在一定时期内,使用同一种促性腺激素(FSH与LH)进行重复超排处理,对母羊卵巢的排卵(排卵反应)以及受精后发情周期等的影响。更多还原

【Abstract】 23 sexually matured Han-ewes were repeatedly treated with FSH and LH, totaling 44 treatments.All the 23 ewes supraovulated at the first treatments, 14 ewes at second, 6 ewes at third,and only 1 at fourth repetitions. The average numbers of ovulation and rates of fertility at the second, third and fourth treatments were 3.3, 7.0, and 4.0; and 87.3%,79.2% and 100%, respectively. Compared with the first supraovulation cycles (11.8 ova and 40.3% fertile), the numbers of ovulation were decreased, but the fertility rates increased, the differences being statistically insignificant (P>0.05), There were 29 ewes coming in heat after supraovulation, average estrous cycle being 19.6 days.更多还原