OTT, B.D.; SECOR, S.M.; University of Alabama, Tuscaloosa; University of Alabama, Tuscaloosa: Metabolic and intestinal responses to feeding for the genus Python
The wide regulation of metabolic and digestive performance to feeding and fasting experienced by the Burmese python (Python molurus) is considered a physiological adaptation to their infrequent feeding habits. To explore the generality of these physiological traits among other infrequently-feeding pythons, we measured postprandial metabolic and intestinal responses of the reticulated python (P. reticulatus), African rock python (P. sebae), and Burmese python. In response to rodent meals 25% of body mass, O2 consumption rates of P. molurus, P. sebae, and P. reticulatus peaked, respectively, at 14, 11, and 9-fold of standard metabolic rates. With a decrease in meal size, peak postprandial O2 consumption rates declined to average 7-fold for the 15% meals and 4-fold for the 5% meals for the three species. Two days following the ingestion of rodent meals 25% of body mass, small intestinal wet mass doubled for the three species, largely as a function of hypertrophy of the intestinal mucosa. Concurrently, intestinal uptake rates of the amino acids L-leucine and L-proline and of the sugar D-glucose increased by 3 to 15-fold over fasting values. As a combined function of intestinal growth and the upregulation of mass-specific nutrient transport, total intestinal uptake capacity increased by factors of 15, 15, and 12-fold for P. molurus, P. sebae, and P. reticulatus, respectively. Demonstrating similar physiological responses to feeding, it appears that these three species of pythons share the adaptive trait of widely regulating digestive performance in response to fasting and feeding.
