Meeting Abstract

64.5  Jan. 7  Long Term Performance Detriments In Songbirds With Extensive Carotenoid-Based Plumage Coloration: Are Carotenoids Toxic? HUGGINS, K.A.*; NAVARA, K.J.; HILL, G.E.; MENDONCA, M.T.; Auburn University; Ohio State University; Auburn University; Auburn University huggika@auburn.edu

Although there is extensive literature addressing the beneficial effects of carotenoids as antioxidants and immune enhancers, there are also studies that indicate that high doses of carotenoids may have a toxic effect. Songbirds with carotenoid-based plumage tend to maintain high levels of circulating carotenoids in plasma, which could represent a potential tradeoff between maintaining brightness at the expense of carotenoid-related toxicities. To test this hypothesis, we maintained American goldfinch males on either a high (n=40) or low (n=40) dose lutein/zeaxanthan treatment for 60 days during molt. We sampled blood from animals before, during, and after supplementation, and analyzed samples for glutathione as a measure of oxidative stress, and creatine kinase as a measure of muscle degradation. Additionally, we tested muscle function using a vertical ascent test, a technique that tests performance capability of pectoral muscles in birds. We found that creatine kinase levels were significantly higher in high dose of dietary carotenoids birds, indicating the presence of muscular degradation. Additionally, high dose birds also significantly reached lower elevation in the jump trials (p=0.009, 2005; p=0.03, 2006) indicating that there was a direct effect between increased carotenoid intake, increased creatine kinase levels and outward physical ability.