西农萨能奶山羊母羔初情期的研究

对30只西农萨能奶山羊母羔的初情期体重、日龄、发情表现,发情周期及17β—雌二醇(17β-E_2)和孕酮(P_4)水平变化进行了研究。研究结果表明:1.初情期体重和日龄分别为10.2(8.0—12.9)kg和54.7(43—71)天,初情期体重和日龄的相关系数为0.798,初情期日龄和出生日期的相关系数则为0.963;2.第一个发情周期平均为8.3(2—37)天,其中短周期(2—8天)羊占62.4％;3.发情表现的特点是阴道和阴门下角有灰白色粘液;4.初情期17β—E_2(pg/ml)/P_4(ng/ml)比值为141.1,17β-E_2和P_4的分泌关系有同步、反步和部分同步部分反步现象。

A STUDY ON FEMALE PUBERTY IN XINONG SAANEN DAIRY GOATS

The pubertal body weight ( BW ) and age, estrous cycle, estrous behavior and relation between 17β-estradiol(l7β-E2) and progesterone (P4) levels in 30 female Xinong Saanen Dairy Goats were studied:(Ⅰ) The average BW and age at puberty were 10.2(8.0 to 12.9)kg and 54.7 (40 to 71) days, respectively; the correlation coefficient between birth date and pubertal age was -0.963. (2) The mean length of the first estrous cycle was 8.34(2 to 37) days, the short cycle ( 2 to 8 days) was 62.4%. (3) The vaginal secretion was grey-white in color.(4)The rate between 17β-E2(pg/ ml ) and P4 ( ng/ml) at puberty was 141.1, and the levels between 17β-E2 and P4 showed synchro-phenomenon ( increased and decreased simultaneous-ly).