Digestive Constraints and Nutrient Hydrolysis in Nestlings of Two Flamingo Species

In vertebrates, enzymatic activity levels in the small intestine are correlated with dietary composition. We examined enzymatic activity levels in juvenile specimens of two flamingo species, Phoenicoparrus andinus and Phoenicoparrus jamesi. Both species feed their chicks with esophageal secretions. Based on the chemical composition of these secretions in flamingoes, we predicted low activity levels of disaccharidases and higher activities of aminopeptidase-N and esterase. As predicted, sucrase was absent in P. andinus, and its activity was low in P. jamesi. Esterase and aminopeptidase-N activities were relatively high. Low maltase activity suggested the presence of carbohydrates in esophageal secretions. Digestive features can have consequences on the growth and survival of chicks. Hence the data presented here may be relevant to the maintenance and reproduction of wild and captive endangered flamingoes.