Rainwater T R, McMurry S T, Platt S G
Institute of Environmental and Human Health (TIEHH), Department of Biological Sciences, Texas Tech University, Lubbock 79416, USA.
J Wildl Dis. 1999 Jan;35(1):125-9. doi: 10.7589/0090-3558-35.1.125.
Two Morelet's crocodiles (Crocodylus moreletii) captured on 21 March 1997 and 20 April 1998 in the New River system, Belize exhibited ectromelia of one forelimb. External and radiograph examination appears to indicate limb agenesis of unknown etiology, as there is no apparent scarring or skeletal trauma. These two individuals represent the only cases of missing limbs from 642 individuals captured in this study and to our knowledge, the first reported cases in Morelet's crocodile. Several factors including age and diet of the reproducing female, extremes in nest conditions (egg incubation temperature and humidity), and exposure to environmental contaminants can cause developmental abnormalities in crocodilians and may have contributed to the condition observed in these animals. Survival rates for hatchling crocodilians are generally low, and embryonic malformations such as ectromelia may constitute an added disadvantage to survival. However, both individuals examined in this study were vigorous and appeared in good condition.
1997年3月21日和1998年4月20日在伯利兹新河系统捕获的两只莫雷莱鳄(Crocodylus moreletii)出现了一侧前肢缺肢畸形。外部检查和X光检查似乎表明是病因不明的肢体发育不全,因为没有明显的瘢痕或骨骼创伤。这两只鳄鱼是本研究中捕获的642只鳄鱼中仅有的肢体缺失案例,据我们所知,也是莫雷莱鳄中首次报告的此类案例。包括繁殖雌性的年龄和饮食、巢穴条件极端情况(卵孵化温度和湿度)以及接触环境污染物在内的几个因素,都可能导致鳄鱼出现发育异常,可能也是造成这些动物出现这种情况的原因。孵化期鳄鱼的存活率通常较低,而诸如缺肢畸形等胚胎畸形可能会增加生存的不利因素。然而,本研究中检查的两只鳄鱼都很活跃,身体状况良好。