Effect of supplementing active dried yeast into laying Japanese quail diets on performance hatching traits and immune response.

Abstract

This study was conducted to evaluate the effect of adding active dried yeast into diets of laying quail on productive performance, immune response and intestinal wall thickness. 300 laying Japanese quail and 100 males were divided into five treated groups of 60 females and 20 males each. For the 8-week experimental period the groups were fed a basal diet supplemented with five graded levels of active dried yeast (Saccharomyces cerevisiae) at 0.0 (control), 0.5, 1, 1.5 and 2%. It was shown that average egg production significantly increased due to adding 1 or 1.5% yeast in the diets. Egg weight improved significantly and the most improvement was recorded at 1.5% yeast level. Egg shell percentage significantly improved due to treatments. Egg yolk and egg albumen was not influenced. Feed intake was not affected, while feed efficiency ratios were enhanced due to adding yeast at 1 and 1.5%, recording 3.45 and 3.39 g feed/g gain, respectively, against 3.75 g feed/g gain for the control. There was no effect on body weight gain. Hatchability improved from 66 (control) to 76.3, 72.1 and 74.6% for 0.5, 1 and 1.5% yeast levels, respectively. Similar improvement was recorded for infertile egg percentage. Embryonic mortality was not affected by treatments. Ovary weight significantly increased, while oviduct weight was not affected. There were a reduction in intestinal wall thickness due to adding 0.5, 1 and 1.5% yeast levels to the diets; however, the 2% level of yeast had an adverse effect on intestinal wall thickness. The WBCs and values of HI titre against sheep RBCs increased significantly due to adding yeast, which may lead to the enhancement of the immune response of laying quail. Blood level of FSH increased significantly, while LH was not affected. In conclusion, supplementation of live yeast into laying quail diets may be useful up to the level of 1.5%.