Meeting Abstract
6.1 Tuesday, Jan. 4 Effect of dietary fatty acids, dietary antioxidants, and training on exercise performance of migratory birds MCWILLIAMS, S.R.*; BAUCHINGER, U.; PIERCE, B.; BOYLES, M.; LANGLOIS, L.; GERSON, A.; PRICE, E.; GUGLIELMO, C.; Univ. Rhode Island; Univ. Rhode Island; Sacred Heart Univ.; Univ. Rhode Island; Univ. Rhode Island; Univ. Western Ontario; Univ. Western Ontario; Univ. Western Ontario srmcwilliams@uri.edu
Fatty acid composition of fat stores affects exercise performance in a variety of vertebrates although few such studies focus on birds. We tested the hypotheses that (a) birds with more essential n-6 PUFA comprising their fat stores have enhanced exercise performance during long-duration (1-4 hr) flights, and (b) that such exercise training causes upregulation of the endogenous antioxidant system of birds. We fed European Starlings (Sturnis vulgaris) one of four diets that differed only in the amount of monounsaturated (MUFA) and polyunsaturated (PUFA) fatty acids, and in the amount of dietary antioxidants. Birds ate more during the 15-day flight training and they added lean and fat mass in response to this training. As expected, dietary fat composition affected fat composition of birds: MUFA-fed birds were composed of more monounsaturated fatty acids and less 18:2n6 than PUFA-fed birds. Blood metabolites measured prior to and immediately following exercise confirmed that birds were metabolizing endogenous fat during exercise. Preliminary analyses suggest that energy expenditure during long-duration flights was similar for birds fed the different diets (ca. 10 W), and that exercise training produced an upregulation of the endogenous antioxidant system. Such whole-animal effects of training and diet composition suggests that phenotypic flexibility enables birds to effectively satisfy the energy costs of flight while reducing the oxidative stress associated with long-duration exercise. Supported by NSF (IOS-0748349), USDA (RIAES-538748), and Canadian Foundation for Innovation (AFAR).
