西农萨能奶山羊公羔初情期的研究

对28只西农萨能奶山羊公羔初情期的体重、日龄、精液、阴囊固(SC)及血浆性腺激素进行了研究,结果是:(1)公羔性行为由不完整过渡到完整,精子发育从无(95.5±10.9日龄)到有(111.3±4.5日龄);(2)初情期体重及日龄分别为10.9±1.4kg和52.0±7.8天;(3)初情期体重与日龄之间呈显著正直线相关(r=0.8340),初情期日龄与出生日期之间呈显著负直线相关(r=-0.9431);(4)羔羊发育早期体重增长较快,SC则在45—150日龄时增长较快;(5)初情期血浆睾酮(T)浓度为1.3±1.1ng/ml,随日龄增加,T呈波动性上升;(6)T和17β-雌二醇(17β-E_2)的分泌呈同步和异步升降。

A STUDY OF PUBERTY IN WALE XINONG SAANEN MILK GOATS

Pubertal age, body weight (BW), scrotal circumference (SC), sexual behavior, semen and plasma gonadal hormones were studied in 28 male Xi-nong Saanen milk goats.Results were obtained as follow:(1) Sexual behavior developed progressively to entirety.Semen was available at 95.5±10.9 days of age and sperm appeared at 111.3±4.5 days of age. (2)Pubertal BW and age were 10.9±1.4 kg and 52.0±7.8 days respectively.Close positive correlation existed between the pubertal BW and age (r = 0.8340); high negative correlation existed between pubertal age and birth date (r = 0.9431) . (3) SC developed fast during 45-150 days of age. (4) Plasma testosterone (T) level was 1.3±1.1ng/ml during puberty and increased with age. (5) Asynchronism or synchronism was shown in the relationship between plasma T and 17β-estradiol levels