Presence of carbohydrate-digesting enzymes throughout the digestive tract of sheep

Abstract

The activity of enzymes that digest carbohydrates at various points in the gastrointestinal tract of sheep was examined. In addition, weight and contents of digestive tract segments were examined. The experiment was performed on six adult ewes fed an 85% hay diet. The morphometric measurements revealed that the alimentary tract constituted 32% of the sheep's body mass and wet rumen contents constituted 70% of wet mass of the total digestive tract content. The protozoal population in the rumen varied from 37.2 × 104 to 54.0 × 104/mL rumen fluid. In the examined samples, ciliates were identified as belonging to the family Ophryoscolecidae, genera Entodinium, Diplodinium, and Ophryoscolex, and family Isotrichidae, genera Isotricha and Dasytricha. Degradation of various carbohydrates by digesta revealed that the fastest digestion rate for plant cell wall carbohydrates and inulin occurred in the reticulum, whereas for starch and chitin, rates of digestion to reducing sugars were the highest in the small intestine. The pH and redox potential at various points in the digestive tract varied from 2.8 to 7.7 and from -72.1 to -289.2 mV, respectively.