VPB 121: Veterinary Physiology - II (2+1)

ABSORPTION

• It is the process whereby the products of digestion and the digested foodstuff form the lumen of the gut is transferred to the blood or the lymph across the epithelial cell membrane.

Site of absorption

• No absorption of food or end products of digestion in the mouth and oesophagus
• In the monogastric animal, absorption in the stomach is very limited.
• However certain drugs  can be absorbed from the pharynx and to a limited extent from the oesophagus.
• The small intestine is the chief site of absorption in the carnivores and omnivores.
• Villi is the the chief site of absorption in small intestine
• The large intestine is the chief organ of absorption in all herbivores (eg. horse) and to a limited extent in the carnivores and man where it is restricted to the initial colon.
• In ruminants, the digestion and absorption of contents is of special importance in the anterior part of the digestive tract.
• The large intestine has specific absorptive sites with respect to water and electrolytes.
• In herbivores, especially in equines, the large intestine absorbs volatile fatty acids and ammonia.