Somes R G, Weigh L A
Poult Sci. 1980 Nov;59(11):2379-85. doi: 10.3382/ps.0592379.
The sexual development of cockerels of three feather growth rate genotypes, k+/k+, Kn/k+, and Kn/Kn, was studied at 2-week intervals from ages 1 to 31 weeks. Body, testis, and comb weights were collected. Histologic evaluation of testes and semen fertility tests were also made. The Kn gene, when homozygous, delayed body growth, and testis growth and development in homozygous males, thus delaying their sexual maturity 2 to 3 weeks. Body weights, relative testis weights, and seminiferous tubule diameters were similar for the k+/k+ and Kn/k+ males but significantly different from the Kn/Kn males. Stages of spermatozoic development were not significantly different between males of any of the genotypes. Regressions of relative testis weight on body weight and of seminiferous tubule size and stage of spermatozoic development on relative testis weight were not different for any of the genotypes. Relative comb size was significantly different between males of all three genotypes. When regressed against relative testis weight, the Kn/Kn males were significantly different from the other two groups of males. The Kn gene exerted an influence, directly or indirectly, which appeared to reduce testosterone production in the Kn/Kn males. The nature of the Kn gene's action was not evident from these data, nor was it clear whether it was acting on the Leydig cells of the testes or on the lutinizing hormone producing cells of the pituitary.
对三种羽毛生长速率基因型（k+/k+、Kn/k+和Kn/Kn）的公鸡从1至31周龄每隔2周进行一次性发育研究。收集体重、睾丸重量和鸡冠重量。还对睾丸进行了组织学评估并进行精液受精测试。Kn基因纯合时会延迟纯合雄性的身体生长、睾丸生长和发育，从而使其性成熟延迟2至3周。k+/k+和Kn/k+雄性的体重、相对睾丸重量和生精小管直径相似，但与Kn/Kn雄性显著不同。任何基因型雄性之间精子发生阶段均无显著差异。任何基因型的相对睾丸重量与体重的回归以及生精小管大小和精子发生阶段与相对睾丸重量的回归均无差异。所有三种基因型雄性的相对鸡冠大小均有显著差异。当与相对睾丸重量进行回归分析时，Kn/Kn雄性与其他两组雄性显著不同。Kn基因直接或间接产生影响，似乎降低了Kn/Kn雄性的睾酮分泌。从这些数据中无法明确Kn基因作用的本质，也不清楚它是作用于睾丸的间质细胞还是垂体中产生促黄体激素的细胞。
