Metabolism and Nutrition: Nutrition III

The influence of the main cereal and feed form of the diet on performance and gastrointestinal tract (GIT) traits was studied in brown-egg laying pullets from hatching to 17 wk of age. There were 8 dietary treatments arranged as a 2 × 4 factorial with 2 main cereals (corn vs. wheat with enzymes) and 4 feeding programs that consisted in changing feed form (mash vs. crumble) according to feeding period. Two of the groups were fed the diets as mash or crumble continuously (1 to 17 wk of age) and the other 2 groups were fed crumbles from 1 to 5 wk or from 1 to 10 wk followed by mash to 17 wk of age. Each treatment was replicated 9 times (40 pullets per replicate). No interactions between main cereal of the diet and feed form program were detected at any age and therefore, only main effects are presented. From 1 to 5 wk of age, pullets fed wheat had higher BW gain (P < 0.001) and better FCR (P < 0.001) than pullet fed corn but the differences disappeared with age. Also at this age, pullets fed crumbles ate less feed (P < 0.001) but had better FCR (P < 0.001) than pullets fed mash. From 1 to 17 wk, pullets fed crumbles continu­ ously had the highest BW gain of all groups (P < 0.001). Also, pullets fed crumbles continuously had better FCR (P < 0.001) than pullets feed mash continuously, with pullets from the other 2 treatments being intermediate. At 17 wk of age, pullets fed corn had heavier (P < 0.001) GIT and gizzards than pullets fed wheat, but body and small intestine length were not affected. Also, pullets fed crumbles continuously had lower (P < 0.001) gizzard and GIT weight but higher (P < 0.001) giz­ zard pH than pullets fed mash continuously. It is concluded that wheat supplemented with enzymes can be used in substitution of corn diets for pullets from 1 to 17 wk of age. Feeding crumbles improved growth performance of the pullets at all ages.