ABSTRACT
The objective of the present study was to evaluate production and egg quality as well as the intestinal morphometry of laying hens fed diets supplemented with marine microalga Dunaliella salina. Six hundred laying hens were allocated based on a completely randomized design into five treatments (0, 0.25, 0.50, 0.75, and 1% inclusion of D. salina biomass) with 12 replicates of 10 hens per treatment. The experiment was divided into three periods of four weeks each, totaling 84 days. During this period, the productive performance of laying hens, the physical-chemical quality of the eggs, and the morphometric alterations of the small intestine and liver were determined. The inclusion levels of D. salina biomass had a linear effect on the performance (egg weight, egg mass, and feed conversion), qualitative parameters (yolk weight and yolk index), and physicochemical parameters of eggs (total carotenoids, TBARS, and yolk color). At the same time, villi lengths and the villus:crypt ratio of the duodenum and ileum segments and the metabolization of carotenoids in the liver were increased as an effect of Dunaliella salina dietary supplementation. Thus, the inclusion of marine microalgae D. salina biomass in experimental diets for laying hens improves the performance, the intestinal health, the physical-chemical quality of the eggs, and at the same time increases carotenoid content and improves egg oxidative stability.
antioxidants; carotenoids; Dunaliella salina; liver; yolk pigmentation