Meeting Abstract

P1.142  Friday, Jan. 4  Comparing digestive and renal traits among populations of the rodents Abrotrhix olivacea and A. longipilis D’ELIA, G.; FEIJOO, M.; LESSA, E.P.; NAYA, D.E.*; PARDIñAS, U.F.J.; TETA, P.; TOMASCO, I.H.; VALDEZ, L.; Universidad Austral de Chile, Chile; Universidad de la Republica, Uruguay; Universidad de la Republica, Uruguay; Universidad de la Republica, Uruguay; Centro Nacional Patagonico, Argentina; Centro Nacional Patagonico, Argentina; Universidad de la Republica, Uruguay; Universidad Austral de Chile, Chile dnaya@fcien.edu.uy

The present study was aimed at evaluating variation in several attributes related to digestive and renal physiology in four populations of Abrotrhix olivacea and four populations of A. longipilis, at from two different latitdues (40ºS and 47ºS) and inhabiting two contrasting biomes (Austral forest and Patagonian steepe) at each latitude. We found that: (1) Except for the southern population of A. longipilis, individuals from the steepe are smaller than individuals from the forest and have lighter small and large intestines; (2) The weight of the stomach and the cecum did not change with latitude or habitat; (3) Kidneys wet mass and the U/P ratio did not show a clear pattern of variation with regard to latitude nor to habitat. However, when data are reanalized as function of the annual rainfall recorded at each locality, it is observed: (1) A positive correlation between (residuals of) small intestine wet mass and rainfall; (2) A negative correlation between (residual of) kidneys wet mass and rainfall only for A. olivacea; (3) A negative correlation between U/P and rainfall. Hence, obtained results indicate that digestive and renal traits are correlated, at the population level, with the accumulated rainfall; that is, with the environmental variable that is probably driving the major differences among the two biomes evaluated. Founded by: FONDECYT 1110737 (Chile), CISC C043-348 (Uruguay), PICT 2008-0547 (Argentina).