Effect of graded dietary inclusion levels of hybrid rye grain on productive performance, the cost-effectiveness of nutrition and egg quality in laying hens

Abstract

Abstract The study was designed to investigate productivity parameters, egg quality and the cost effectiveness of feeding laying hens with diets where ground wheat was replaced with varying levels of whole hybrid rye grain cv. Brasetto. A total of 396 Hy-Line Brown hens at 34 weeks of age were allocated to three treatment groups with 66 replicates (cages) of two hens each, and were fed isocaloric and isonitrogenous pelleted diets for 12 weeks. The diet for control group hens (R0) did not contain rye grain. In diets for hens from groups R100 and R200, ground wheat grain was partially replaced with whole rye grain at 100 g/kg and 200 g/kg, respectively. Whole intact rye grains were included in the diets. The cost of diets containing 10% and 20% of whole rye grain was by approximately 1.0% and 1.9% lower, respectively, compared with the control diet that contained no rye grain. During the entire 12-week feeding period, dietary treatments had no effect on laying rate (95.64% to 97.07%), egg weight (62.51 g to 62.74 g) or egg mass output (5.04 kg to 5.12 kg per hen). The inclusion of whole rye grain in layer diets caused a linear increase in feed intake (P < 0.047) and tended to linearly increase the feed conversion ratio (FCR, P = 0.078). Both groups of hens fed diets containing whole rye grain were characterized by a linear decrease in the dry matter (DM) content of excreta (P = 0.001). Increased excreta moisture was accompanied by a tendency towards a higher incidence of dirty eggshells in R200 hens (P = 0.068). The inclusion of 100 g/kg of whole rye grain in layer diets decreased the cost of feed per kg of eggs by 1.9%. Dietary treatments had no significant effect on eggshell thickness (0.330 mm - 0.345 mm), albumen quality (Haugh units, 83.46 – 85.84) or yolk color (3.8 - 4.0). The results of this experiment indicate that pre-pellet inclusion of whole rye (at up to 200 g/kg) in diets with supplemental NSP-degrading enzymes and phytase can be an effective and economically viable alternative to ground wheat in pelleted layer diets.