温湿度对山地麻蜥孵化卵、孵化成功率及孵出幼体特征的影响

Influence of Thermal and Hydric Environments on Egg Incubation,Hatching Success,and Hatchling Traits in a Lacertid Lizard,Eremias brenchleyi

用 6种温湿度条件孵化安徽宿州乾山山地麻蜥 (Eremiasbrenchleyi)卵 ,观测孵化卵质量变化、胚胎利用卵内物质和能量以及孵出幼体特征。卵在产出后 1h内收集 ,共设置 3× 2种温湿度处理 (温度分别为2 7、 30和 33℃ ;湿度分别为 - 2 2 0、 0kPa)。每隔 5d称卵重 ,直至幼体孵出。幼体经测量、称重后 ,解剖、分离为躯干、剩余卵黄和脂肪体三组分 ,用于成分测试。卵从环境中吸水导致质量增加 ,孵化温、湿度及其相互作用显著影响孵化卵的质量变化 :同一温度下 ,高湿度 (0kPa)孵化卵的终末质量大于低湿度 (- 2 2 0kPa)孵化卵 ;同一湿度下 ,低温 (2 7和 30℃ )孵化卵的终末质量大于高温 (33℃ )孵化卵。温度显著影响孵化期 ,随温度的升高孵化期缩短 ;湿度及其与温度的相互作用对孵化期无显著影响。孵化温湿度对孵化成功率无显著影响。温度显著影响胚胎对卵内物质的动用、幼体大小、质量以及剩余卵黄质量 ;除剩余卵黄外 ,湿度及其与温度的相互作用不影响山地麻蜥孵出幼体几乎所有的被检测特征。 33℃孵出幼体的大小和质量均显著小于 2 7和 30℃ ,并特征性地具有较大的剩余卵黄。因此 ,33℃不适宜孵化山地麻蜥卵。 2 7℃和 30℃中孵出幼体躯干发育良好 ,各项被测定的特征指标极其相似。

Influence of thermal and hydric environments on incubation eggs,embryonic use of energy and hatchling traits were studied in the lacertid lizards,Eremias brenchleyi,which were collected in Qianshan,Suzhou,Anhui,Eastern China.The eggs were incubated at temperatures of 27,30,and 33 ℃ on substrates with water potentials of 0 and -220kPa using a 3×2 factorial design. Laid eggs were collected in one hour.Eggs were weighed at five-days intervals till hatchlings from eggs incubated.Each hatchling was thawed and separated into carcass,residual yolks,and fat bodies after measured and weighed.The components were preserved frozen for later determination of composition.All viable eggs increased in mass throughout the course of incubation due to absorption of water,and both thermal and hydric environments affected water exchanges between eggs and their surroundings.Final eggs incubated in wetter substrates (0kPa) gained more mass than did eggs in drier substrates (-220kPa) but at the same temperature;final eggs incubated at 27 and 30℃ gained more mass than did eggs at 33℃ but at the same substrate water potential.Incubation temperature significantly affected duration of incubation,and which decreased as incubation temperature increased,but substrate moisture and its interaction with temperature did not.Both incubation and substrate moisture did not affected hatching success.Substrate moisture and its interaction with temperature were unaffected almost all hatchling traits examined except residual yolk.However,Incubation temperature profoundly affected embryonic use of nutrients and size,mass,and residual yolk mass of hatchlings.33℃ was not a suitable incubation temperature for E.brenchleyi eggs,because eggs incubated at 33℃ produced smaller hatchlings that contained larger residual yolks than did eggs incubated at 27℃ and 30℃.Given that eggs incubated at 27℃ and 30℃ both produced well-developed hatchlings of which all measured variables were nearly the same,we conclude that 30℃ is better than 27℃ for incubation of E.brenchleyi eggs because of the shortened duration of incubation at 30℃.