人工驯养下扬子鳄的生长规律

研究结果表明扬子鳄在饲养条件下的生长具有一定的规律性。饲养群体中,5龄以前的鳄生长速率较快,其中在2龄前生长速率最快,在5龄至7龄间生长速率明显减慢;鳄体长与体重之间呈正相关,两者在体长小于50cm时呈直线相关,体长大于50cm时呈曲线相关。不同性别的扬子鳄年生长状况不同,从5龄开始雌雄鳄体重出现显著差异,雄鳄重于雌鳄;从6龄开始雌雄鳄在体长方面的生长速率出现差异,雄鳄生长明显快于雌鳄;达到10龄后,雌雄鳄在体长和体重方面的增长均明显减慢,达到15龄时两者的体形已相差悬殊,雄性大于雌性。由von Berta-lanffy生长模型分析,雌鳄达到25龄而雄鳄达到35龄后,各自的体长几乎停止生长,雌鳄平均最大体长为173cm,雄鳄平均最大体长为219cm。在人工越冬下,除第一次越冬外,扬子鳄在越冬室内的冬眠中体况无明显变化,体能明显消耗出现在户外冬眠过程中。本研究为扬子鳄的科学化饲养提供理论依据。

Growth regularity in captive Chinese Alligator, Alligator sinensis

The studies in this paper revealed that Chinese Alligator's growth has a regularity in captive conditions.In captive population,growth rates of A.sinensis were much higher before 5 years old,and highest before 2 years old,and significately slowed down between 5 and 7 years old.There was a positive correlation between body length and body weight of the alligators,which presented linear correlation under 50cm in body length,and curve correlation over 50cm in body length.Growth of alligators is also different between male and female,which,the body weight between sexes revealed that the male was significantly heavier than the female from beginning of 5 years old,and the growth rate of male was higher than that of female from beginning of 6 years old.After 10 years old,both index in male and female slowed obviously down in body length and body weight,and up to 15 years old bodily form was quite different from the male and female,the male was far larger than the female.According to analysis using von Bertalanffly growth model,both sexes of the alligators would hardly grow in body length after 25 years old of the female and 35 years old of the male,respectively.In overall population,the maximum body length of the female alligators would come to 173cm,of the male alligators come to 219cm.Among artificial overwintering except the first overwintering,the bodily state of A.sinensis didn't change evidently in hibernation inside wintering chamber,a marked consumption of physical energy occurred in the progress of outdoor hibernation.This result will provide theoretical basis for scientific breeding of A.sinensis.