DIGESTIVE RESPONSE TO THE FIRST MEAL IN HATCHLING BURMESE PYTHONS (PYTHON-MOLURUS)

Juvenile Burmese pythons (Python molurus) undergo dramatic increases i n intestinal nutrient transport, hypertrophy of intestinal mucosa, and very large increases in metabolic rate in response to feeding. This s tudy investigates whether hatchling P. molurus, after their very first meal, experience magnitudes of digestive responses greater than or eq ual to those occurring for juveniles that have consumed many previous meals. After consuming their first meal, hatchling P. molurus increase d oxygen consumption rates 12-fold, up-regulated intestinal nutrient t ransport three- to fourfold, and experienced a twofold increase in sma ll intestinal wet mass. One day after feeding, their stomachs and live rs significantly increased in mass, whereas the mass of their gallblad ders significantly decreased. These postfeeding responses of hatchling s are similar in magnitude and mass-specific values to those of juveni le P. molurus. Thus, young P. molurus up-regulate intestinal nutrient transport and undergo intestinal hypertrophy to the same magnitudes af ter their first meal as they do following future meals. The significan ce of this phenomenon is that, at the completion of digestion, the sma ll intestine of juvenile pythons atrophies and down-regulates its func tions to values comparable to those of the naive gut of hatchlings. Th is study demonstrates that, regardless of previous digestive history, the intestine of young P. molurus exhibits conserved magnitudes of pos tfeeding responses and that, during digestive quiescence, the energeti c cost of maintaining the intestine is minimized.