Fish Nutrition and Feed Technology (2+1)

Unit 14 - Digestive enzyme, digestibility and factors affecting digestibility

14.1.Digestion and Absorption

Digestion is the process by which the ingested food material is broken down in to simple, small, absorbable molecules, while absorption refers to diffusion and active transport of products of digestion in to fish tissue. Digestion is a progressive process, beginning in the stomach and possibly not ending until food leaves the rectum as faeces. The task of digestion is performed primarily by the digestive enzymes, which are secreted in to the lumen of the alimentary canal from the oesophageal, gastric, pyloric caecal and intestinal mucosa and from the pancreas.