Effects of partially hydrolysed guar gum on feeding behaviour and crop emptying rate in chicks.

1. The effects of partially hydrolysed guar gum (PHGG) or intact guar gum (GG) on feeding behaviour and crop emptying rate in growing chicks were investigated. 2. Several combinations of dietary PHGG and GG at 50 g per kg diets were prepared for a feed intake experiment. Birds (1 7-d-old) were given diets for 3 h after 16 h fasting, and food consumption was measured at 1 h intervals. The food intake rapidly decreased as the dietary GG content increased even at 1 h after feeding. 3. The rate of food passage from the crop was also investigated with birds (20-d-old after 16 h fasting. Birds were tube-fed diets having several ratios of dietary PHGG and GG. After 1 h of feeding, the diet remaining in the crop was measured after drying. The crop emptying rate decreased linearly as dietary PHGG concentration decreased. 4. The present study suggests that partial hydrolysis of dietary GG improve both feeding behaviour and food passage from the crop in growing chicks.