Gastro-Intestinal Response and Passage Time of Pelleted Diets in Digestive Tract of Broilers

Abstract

An experiment was conducted to examine the effect of pellet size and fibrous diet on intestinal passage time of feed in the digestive tract of broilers. A total of 64 day old chicks were used in a completely randomized factorial design with two different diets (copra meal and corn-soy based diets) and two pellet size (fine and coarse). On day 1-5 of week seven, the birds were fed the experimental diets. On day 6, after a 12 h feed restriction, all birds were orally administered with 85 mg chromium oxide in a gelatine capsule. Four birds per treatment were killed by cervical dislocation. Gizzard and small intestine were weighed and opened. The colour of the digesta observed to visually determine the location of the chromium oxide. The faeces were observed for first appearance of entire coloured faeces and then on an hourly basis up to the disappearance of coloured faeces. The experimental design was a two way factorial with two basal diets and pellet sizes. Data indicated that a copra meal diet moved in the digestive tract was slower than a corn-soy diet. The first appearance of the marker in the faeces of birds fed the copra meal diet was 52 min later than for those fed the corn-soy diet. The movement in the digestive tract of the fine ground diets was slower than that of the coarse diets. The effect of pellet size on feed passage time was only evident in the copra meal based diet.