Effect of pre-starter diet ingredients and moisture content on performance, yolk sac utilization and small intestine morphology in broiler chickens

A 5 × 2 factorial experiment was conducted to investigate the impact of different iso-energetic and iso-nitrogenous pre-starter diets varying in nutritive ingredients and moisture content on growth parameters, yolk sac utilization and intestine morphology of broiler chickens. A total number of 600-day-old Ross 308 male broiler chicks were randomly assigned to 10 experimental treatments, each replicated 4 times, with 15 birds per replicate for 42 days. Dietary treatments included a control diet supplemented by each of the four combination of casein and dextrose (CD), casein and starch (CS), gluten and dextrose (GD) or gluten and starch (GS) prepared in either dry or semi-moist form by adding 0.3 L water/kg diet (SmControl, SmCD, SmCS, SmGD and SmGS) and fed from day 1 to day 7. Diet composition and moisture content interacted for feed intake (FI), weight gain (WG) and feed conversion ratio (FCR) over the first week and entire period of the study. Feeding birds with semi-moist diets caused an increase (P < 0.001) in final WG (days 1-42) in the birds fed control, GD and GS accompanied with an improved in FCR except for the control. Moisturising the diets increased the length of chickens at day 3 (P < 0.05) and day 5 (P < 0.01) and decreased carcass (P < 0.05) fat when assessed independent of diet composition. On day 7, diets and moisture content interacted for the jejunal crypt depth where birds fed SmGD and SmGS showing the lowest figures compared with control group of birds. To conclude, inclusion of GD and GS in semi-moist form in pre-starter diets would result in increased FI, improved gut development and feed efficiency and a carryover effects on productive traits can be observed at later stages of growth.