School of Life Sciences, Arizona State University, PO Box 874601, Tempe, AZ 85287-4601, USA.
J Comp Physiol B. 2011 May;181(4):551-63. doi: 10.1007/s00360-010-0529-z. Epub 2010 Dec 8.
Developmental conditions affect adult physiological processes and phenotypic traits, including those associated with both survival and reproduction. Carotenoids are molecules that generate sexually attractive coloration, and these pigments are acquired throughout life and can affect antioxidant capacity and immunocompetence of young and old animals. However, few studies have tracked carotenoid status and condition during development and into adulthood to understand how ontogeny affects later-life health and coloration of both males and females. We reared male and female mallard ducks (Anas platyrhynchos) from hatch to adulthood, measured circulating carotenoid titers and body condition (i.e., size-adjusted body mass) throughout development, and assessed adult immune function and integumentary carotenoid-based beak and foot coloration. We found that adult immune function (wing web swelling response to phytohemagglutinin; PHA) in males was positively correlated with body condition during the growth period of development, rather than adult condition, and similarly that both male and female beak coloration was associated with developmental, rather than adult, body condition. We also found associations between coloration and health during adulthood; males with more carotenoid-rich beaks (a sexually attractive feature) tended to have a more robust adult PHA response and a greater antibody response to a novel antigen, while females with less carotenoid-rich beaks had greater antibody responsiveness at adulthood. In addition, male beak color changed over the course of the 24-h PHA test in proportion to the degree of PHA swelling. However, intensity of foot coloration (a trait of unknown sexual significance) was not associated with any condition, carotenoid, or immune metric for males or females. Taken together, our findings implicate key developmental components to the expression of both survival- and reproduction-related traits at adulthood, but that for a dynamic trait like beak color, there are also important adult conditions that can alter signal expression.
发育条件会影响成年的生理过程和表型特征，包括与生存和繁殖相关的特征。类胡萝卜素是产生有吸引力的颜色的分子，这些色素是在整个生命过程中获得的，它们可以影响年轻和年老动物的抗氧化能力和免疫能力。然而，很少有研究追踪类胡萝卜素的状态和状况从发育到成年，以了解个体发育如何影响雄性和雌性个体的晚年健康和颜色。我们从孵化到成年饲养雄性和雌性绿头鸭（Anas platyrhynchos），在整个发育过程中测量循环类胡萝卜素浓度和身体状况（即大小调整后的体重），并评估成年免疫功能和羽毛和脚的类胡萝卜素着色。我们发现，雄性的成年免疫功能（对植物血凝素的翅膀网络肿胀反应；PHA）与发育过程中的生长期间的身体状况呈正相关，而不是与成年状况呈正相关，同样，雄性和雌性的喙颜色与发育时期有关，而不是成年时期。我们还发现成年时期的颜色与健康之间存在关联；具有更富含类胡萝卜素的喙（一个有吸引力的性特征）的雄性往往具有更强壮的成年 PHA 反应和对新抗原的更大抗体反应，而喙中类胡萝卜素含量较低的雌性在成年时具有更强的抗体反应。此外，雄性喙的颜色在 24 小时 PHA 测试过程中会根据 PHA 肿胀的程度而变化。然而，脚颜色的强度（一个未知的性别意义的特征）与雄性或雌性的任何状况、类胡萝卜素或免疫指标都没有关联。总的来说，我们的发现表明，关键的发育成分与成年时的生存和繁殖相关特征的表达有关，但对于像喙颜色这样的动态特征，还有重要的成年状况可以改变信号表达。
