Meeting Abstract

100.9  Wednesday, Jan. 7  Impact of meal fat content on the postprandial responses of the Burmese python SECOR, Stephen M.*; LIGNOT, Jean-Herve; University of Alabama; CNRS, DEPE, Strasbourg ssecor@biology.as.ua.edu

Prey vary significantly in body fat as a function of season and the availability and composition of their diet. Largely unknown is the impact that meal fat content has on postprandial metabolism and gastrointestinal performance. We assessed the effects of meal fat on the metabolic, morphological, and physiological responses of Burmese pythons (Python molurus). Pythons responded to rodent meals (25% of body mass) of 5, 10, and 20% body fat by increasing oxygen consumption rates that peaked at 12.8, 15.0, and 11.8-fold of standard metabolic rates, respectively. Specific dynamic action was significantly greater for the 20% fat meals compared to the 5 and 10% fat meals. Passage from the stomach was slower for the 20% fat meals, such that by day 4 of digestion 48% of the 20% fat meals remained in the stomach compared to 12% of the 10% fat meals. Meals 5% body fat induced no postfeeding change in small intestinal mass, whereas the small intestine more than doubled in mass for the 20% fat meals. Fat droplets were absent from small intestinal enterocytes for the 5% fat meals, present in the anterior half of the intestine for the 10% fat meals, and found throughout the small intestine for the 20% fat meals. Microvilli were noticeably longer for the 5% fat meals compare to the other meals. Ventricular mass increased by 25-30% for the 5 and 10% fat meals and by 50% for the 20% fat meals. Kidney mass increased by 60, 75, and 100% for the 5, 10, and 20% fat meals, respectively. Small intestine nutrient uptake rates, although averaging higher for the 5% fat meals, did not significantly differ among diets. Due to differences in small intestinal mass, intestinal uptake capacities of amino acids was significant less for the 5% fat meals compared to the 20% fat meals. For the python, high fat content of their diet slows digestion and impacts intestinal morphology and function.