The effect of insoluble fibre and intermittent feeding on gizzard development, gut motility, and performance in broiler chickens

Abstract

A trial was conducted to test the following hypothesis; broiler exposure to coarse insoluble fibre in the diet or litter will result in enhanced gizzard function and performance, improved adaptability to an intermittent feeding program and an increase in the occurrence of reverse peristalsis. Ross 308 broiler chickens were either intermittent or ad libitum fed a basal diet, a basal diet diluted with 15 % coarse hulls (barley and oats) or a basal diet diluted with 15 % finely ground hulls in a 2x3-factorial experiment (n = 17 birds/treatment). From 18 days of age, the birds were transferred to individual cages. Birds on intermittent feeding had restricted access to feed from 11 days of age. From 18 days of age, the restrictive feeding program consisted of four one-hour meals and one two-hour meal per day. AME value and faecal starch digestibility were determined by quantitative collection of excreta. At 31 and 32 days of age, birds were inoculated with CrEDTA via the cloaca. Weights were recorded and digesta samples collected from the gizzard, duodenum, jejunum, and ileum. There was no interaction between diet and feeding regime for any of the parameters measured. The addition of coarse oat and barley hulls resulted in birds with fuller, heavier gizzards (p < 0.001). Intermittently fed birds raised on the coarse hull diet exhibited an improved starch digestibility compared to birds not exposed to hulls (p < 0.001). The presence of chromium in all intestinal tract sections of birds from the six treatment groups, confirms that reflux occurs along the entire length of the gastro intestinal tract, irrespective of insoluble fiber content of the feed or feeding regime.