Improving the Use of White Lupine in the Laying Quail Feeding by Enzymes Addition: Effects on Productive Performances, Digestion, Blood Biochemical Indices and Eggs Quality

Abstract

Lupine seeds are a valuable nutritive source for animal feeding, but for poultry nutrition, the content in crude fiber and non-starch polysaccharides (NSP) have an antinutritional factor. The aim of this research was to highlight the effect of partial soybean meal replacement with L. albus seeds and enzyme addition in the laying quail diets on productive performance, digestion, blood biochemical indices and egg quality. A total of 210 homogenous female Japanese quails (Coturnix japonica) at 24 week of age were randomly assigned to 6 dietary treatments, with the standard diet based on soybean meal unsupplemented (−) and supplemented with enzyme (+) (S−/S+) and the experimental diets on which the soybean meal was based partially substituted by including lupine in the amount of 200 g/kg and 250 g/kg, unsupplemented and supplemented with enzymes (L20−/L20+; L25−/L25+).The use of enzymes in the lupine-based diets allowed increasing the proportion of lupine in the diet of laying quails by up to 25% (% of feed) without changing egg production, egg weight, feed conversion rate and physical–chemical quality parameters of the eggs. In addition, the use of lupine (−/+) improved (p < 0.001) the carotenoid content of the egg yolk, as well as the quality of the yolk fats by decreasing the cholesterol content and the level of fatty acids (FA) with an atherogenic effect, in favor of omega-3 FA. Enzyme supplementation of the lupine-based diets had a negative effect on the health lipid indices of the fats in the yolk (ratio of the hypocholesterolemic/Hypercholesterolemic FA—h/H, atherogenic index—AI, thrombogenic index—TI and health promotion index—HPI). The use of exogenous enzymes increased the nutrients’ efficiency of the quails’ feed, which is supported by the improvement of the blood metabolic indices and a decrease of intestinal digesta viscosity and feces moisture. In conclusion, white lupine can be used up to 25% in the laying quail feed in association with specific enzymes without affecting the productive performance and egg quality; moreover, lupine use has improved the quality of the eggs, increasing humans’ health.