Sunflower meal as a nutritional and economically viable substitute for soybean meal in diets for free-range laying hens

Alternative feedstock which may partially or fully replace conventional ingredients and consequently reduce the cost of egg production have been sought for a long time. In this context, the aim of this study was to evaluate the performance, egg quality and profitability of Naked Neck laying hens fed different levels of sunflower meal in,place of soybean meal. A total of 128 hens were used, distributed in a completely randomized design, 16 boxes with eight hens each. The treatments consisted of one reference diet (RD) and three diets replacing the crude protein of soybean meal with sunflower meal at levels of 10%, 20% and 30% (R10, R20 and R30, respectively), properly supplemented with synthetic amino acids. All diets were based on the nutritional requirements of the semi-heavy laying hens. There was no significant difference of the different levels of substitution of soybean meal by sunflower meal on the laying rate (P= 0.14), egg mass (P = 0.06), feed conversion (P = 0.20) and egg weight (P = 0.35). However, for egg quality yolk color showed significant effects at different levels of substitution. The economic analysis of dietary treatments showed a reduction in the price per kilogram of soybean meal (0.59; 0.57; 0.55 and 0.53 dollars, respectively) replaced by sunflower meal at levels of 0%, 10%, 20% and 30% protein gross. Thus, the partial replacement of crude protein of soybean meal by sunflower meal in diets for hens is economically feasible, provided that the amino acid profile is corrected through supplementation, allowing the maintenance of the main quantitative and qualitative indices. (C) 2016 Elsevier B.V. All rights reserved.