Sterilization of fish by high temperature

莫桑比克罗非鱼幼鱼从孵化后3天开始在高温（37 ℃）下饲养50天。所有个体的性腺均为不育。不育雌性动物未表现出性行为或表现出雌性婚姻色，组织学分析显示热处理雄性动物睾丸中不存在所有阶段的生精生殖细胞;然而，观察到位于输出管内衬的上皮细胞层内的结构积极分泌精子液进入导管，这也见于正常雄性动物的成熟睾丸。不育的男性仍然显示男性婚色，积极挖掘产卵巢，并与正常的成熟女性交配。然而，与这些雄性交配的雌性最初正常地孵卵，但在4至5天过早地释放它们。所有释放的卵都没有受精，而且都死了。

Juveniles of the Mozambique tilapia, were reared from 3 days after hatching at a high temperature (37 degree centigrade) for 50 days. The gonads of all individuals were sterile. Sterile females did not display sexual behavior or exhibit female nuptial coloration, Histological analysis revealed the absence of all stages of spermatogenic germ cells from the testes of the heat-treated males; however, structures within the layer of epithelial cells lining the efferent ducts were observed to be actively secreting sperm fluid into the ducts, as also seen in the mature testes of normal males. The sterilized males nonetheless displayed male nuptial coloration, actively dug spawning nests, and mated with normal mature females. However, females mated with these males initially brooded their eggs normally but released them prematurely at 4 to 5 days. All the released eggs were unfertilized, and all were dead.