DuRant S E, Hopkins W A, Carter A W, Stachowiak C M, Hepp G R
Department of Fish and Wildlife Conservation, Virginia Tech, Blacksburg, Virginia 24061, USA.
Physiol Biochem Zool. 2013 Jul-Aug;86(4):410-20. doi: 10.1086/671128. Epub 2013 May 31.
Recent research in birds suggests that investing in incubation is one mechanism by which parents can enhance the phenotype of their offspring. Posthatch environmental conditions can also shape an individual's phenotype, and it is thus possible for pre- and posthatch conditions to have interactive effects on an individual's phenotype. In this study, we examined the individual and interactive effects of prehatch incubation temperature and posthatch food availability on growth, food consumption, and thermoregulatory ability in wood duck (Aix sponsa) ducklings. Eggs were incubated at one of three temperatures (35.0°, 35.9°, or 37.0°C), and then ducklings were reared on an either ad lib. or time-restricted diet for 12 d after hatching. We found that food availability influenced duckling growth, with the slowest growth occurring in ducklings fed the restricted diet. Incubation temperature also interacted with food conditions to influence duckling growth: ducklings fed ad lib. from the lowest incubation temperature grew slower than ducklings fed ad lib. from the higher incubation temperatures. Most importantly, we found that the improvement in a duckling's ability to maintain body temperature in the face of a thermal challenge was influenced by embryonic incubation temperature but not feeding conditions. Ducklings from the highest incubation temperature experienced the greatest improvement in thermoregulatory performance with age. Our findings suggest that the prehatch environment is more important than posthatch resource conditions in determining some physiological functions and underscores the important role that incubation temperature plays in determining offspring phenotype in birds.
近期对鸟类的研究表明，投入精力进行孵化是亲代增强子代表型的一种机制。孵化后的环境条件也会塑造个体的表型，因此孵化前和孵化后的条件可能会对个体的表型产生交互作用。在本研究中，我们考察了孵化前的孵化温度和孵化后的食物可获得性对林鸳鸯（Aix sponsa）雏鸭生长、食物消耗和体温调节能力的个体影响及交互作用。将卵在三种温度（35.0°、35.9°或37.0°C）之一进行孵化，然后雏鸭在孵化后12天内自由采食或限时进食。我们发现食物可获得性影响雏鸭生长，喂食受限饮食的雏鸭生长最慢。孵化温度也与食物条件相互作用影响雏鸭生长：从最低孵化温度开始自由采食的雏鸭比从较高孵化温度开始自由采食的雏鸭生长慢。最重要的是，我们发现雏鸭在面对热挑战时维持体温能力的提高受胚胎孵化温度影响，而非喂食条件。孵化温度最高的雏鸭随着年龄增长体温调节性能改善最大。我们的研究结果表明，在决定某些生理功能方面，孵化前环境比孵化后资源条件更重要，并强调了孵化温度在决定鸟类子代表型中所起的重要作用。
