After feeding the python undergoes rapid organ growth primarily in the small intestine. As seen on the graph below, within 6 hours of feeding the mass of the small intestine begins to increase. After about 3 days, the mass of the small intestine peaks at about twice the weight during fasting and remains at this elevated level until about 6 days after feeding. Finally, after about 2 weeks, the intestinal mass returns to fasting levels (Secor and Diamond, 1995). Most of the increase in the mass results from an increase in the mucous volume and the length of the microvilli (Secor and Diamond, 1998).
Figure 1 used with permission of (Secor and Diamond, 1995)
Other organs also grow in response to feeding because of the increased work load of digestion. The liver, stomach, kidney, heart and pancreas all increase substantially in mass after about 3 days of digestion. Conversely, the gall bladder decreases in mass after feeding because of the large release of bile into the stomach (Secor and Diamond, 1995).
After feeding the uptake rates of amino acids and sugars in the intestine increase significantly above fasting levels. Also, the ratio of amino acids to sugars uptaken in the small intestine is significantly lower during digestion than during fasting. This means that during digestion sugar is uptaken at a higher rate than during fasting (Secor et al, 2000).