An experiment was carried out to verify the effect of different dietary Na levels on the performance and egg quality of laying Japanese quail during the peak of production (69 to 132 days old). A total of 300 laying Japanese quails aged 69 days was allocated to 30 experimental units with ten birds each. The quails were assigned to a completely randomized design, with five treatments, six replicates. The Na levels studied were 0.017, 0.083, 0.149, 0.215, and 0.281% corresponding to 0.000, 0.166, 0.332, 0.499, and 0.665%, respectively, of salt inclusion in the diets. The experimental diets were isoproteic (20.0% CP), isoenergetic (2,900 kcal ME/kg) and isocalcium (3.2% Ca). It was observed linear increase of egg production, feed conversion by egg mass, albumen and yolk percentage and egg specific gravity with the increase of Na in the diet. Quadratic effect was observed for feed intake, weight egg, egg mass/bird.day, final body weight, eggshell thickness and Haugh unit. No effect of Na levels was observed of on feed conversion of dozen-egg, eggshell percentage, viability and moisture in the excreta of birds. Diets containing 0.281%Na, corresponding to a daily intake of 69.1 mg Na/hen, increased performance and egg quality of laying Japanese quail during the peak of production. However, a satisfactory performance, based on production of egg/hen.day and commercial egg production can be obtained with birds fed diet containing 0,149% de Na.
Coturnix coturnix japonica; egg quality; egg production; salt
