ASPECTS OF THE SEXUAL DEVELOPMENT OF BRAHMAN VERSUS ANGUS BULLS IN FLORIDA
ASPECTS OF THE SEXUAL DEVELOPMENT OF BRAHMAN VERSUS ANGUS BULLS IN FLORIDA
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DOI：
10.1016/0093-691x(82)90045-0
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发表时间：
1982-01-01
期刊：
影响因子：
2.8
通讯作者：
CORNELISSE, KW
中科院分区：
文献类型：
--
作者：
FIELDS, MJ;HENTGES, JF;CORNELISSE, KW
对10头8-20月龄婆罗门公牛和12头8-20月龄安格斯公牛的断奶后生长和繁殖性状进行了研究。年龄。婆罗门公牛在15.9岁时进入青春期。0.4密苏里州年龄，体重432 .+-。16 kg，阴囊周长（SC）为33.4 ±。1.2 cm，血浆睾酮为3.96 ± 0.001。1.03 ng/ml。在整个研究中，SC平均值的品种差异不显著。The breed. times.日间相互作用（B ×D）（P < 0.01）显示，最初，Brahman SC小于安格斯SC;到研究结束时，Brahman SC大于安格斯SC。当SC校正体重时，品种差异（P < 0.01）和B ×. SC/体重（BW）的D值（P < 0.01）反映了婆罗门公牛进入青春期的年龄较晚，体重较重。血浆睾酮在不同品种间差异显著（安格斯>婆罗门，P < 0.01），随年龄增长呈线性增长（P < 0.01）。没有B时代。血浆睾酮水平。没有观察到精子浓度的品种差异。其它精液性状差异显著（P < 0.01），前向运动率、精子活力、总畸形率和精液量。A B ×D（P < 0.01）对这些精液性状的品种差异也很明显。布拉汉姆公牛的性发育发生在较晚的实足年龄，并且与安格斯公牛的性发育模式不平行。动物之间的变化，在SC的婆罗门和本研究和其他报告之间的差异表明，在SC的差异存在于不同群体的布拉汉姆公牛，并应提供机会，在此性状的选择进展。
Postweaning growth and reproductive traits were studied in 10 Brahman and 12 Angus bulls from 8-20 mo. of age. Brahman bulls reached puberty at 15.9 .+-. 0.4 mo. of age, weighed 432 .+-. 16 kg, had a scrotal circumference (SC) of 33.4 .+-. 1.2 cm, and plasma testosterone of 3.96 .+-. 1.03 ng/ml. Breed differences in SC averaged over the entire study were not significant. The breed .times. day interaction (B .times. D) (P < 0.01) showed that, initially, the Brahman SC was smaller than the Angus SC; by the end of the study the Brahman SC was larger than the Angus. When SC was adjusted for body weight, breed difference (P < 0.01) and B .times. D (P < 0.01) for SC/body weight (BW) reflected the later age and heavier weight at which the Brahman bull reached puberty. Plasma testosterone differed between breeds (Angus > Brahman, P < 0.01) and increased at a linear (P < 0.01) rate with age. There was no B .times. D in plasma testosterone. No breed differences in sperm concentration were observed. Other semen traits were different (P < 0.01), i.e., rate of forward movement, sperm motility, total abnormalities and semen volume. A B .times. D (P < 0.01) was also evident for breed differences in these semen traits. Sexual development of the Braham bull occurred at a later chronological age and in a nonparallel pattern to that of the Angus. Between animal variation in SC within the Brahmans and differences between this study and other reports suggest that differences in SC exist for various populations of Braham bulls and should provide opportunities for progress in selection for this trait.