Effect of Chromium-methionine Chelate on Performance and Some Plasma Constituents of Laying Japanese Quail during Summer Months

A 12-wks laying trial was conducted to study the effect of dietary chromiummethionine chelate supplementation on laying Japanese quail (Coturnix coturnix japonica) performance, egg quality, fertility %, hatchability % and some plasma constituents during summer months. A total of 225 laying Japanese quail (150 ♀+ 75 ♂) of 8 wks old were randomly assigned in 5 equal groups of 3 equal replicates each. A corn-soybean meal basal layer diet was formulated to contain 20% CP and 2900 kcal ME/kg diet. Five experimental dietary treatments were studied in this study; the 1 st group of birds was fed the corn-soybean meal basal diet without chromium (Cr) supplementation as a control group. The 2 nd , 3 rd , 4 th and 5 th groups were fed the basal diet supplemented with 200, 400, 800 and 1200 μg Cr/kg diet, respectively. Chromium-methionine chelate was the source of the supplemental Cr. The results showed that Cr addition to quail layers diets at levels of 400, 800 or 1200 μg/kg diet significantly increased egg number, egg production %, Haugh unit, shell thickness, plasma albumin and plasma calcium as well as decreased plasma glucose. Supplementing Cr at levels of 800 or 1200 μg/kg diet significantly increased activity of aspartate aminotransferase and alkaline phosphatase and decreased plasma cholesterol and triglycerides. Supplementing Cr at a level of 1200 μg/kg diet significantly increased egg weight, egg mass, hatchability %, plasma total protein, plasma globulin, alanine aminotransferase activity and gave the best feed conversion ratio. In conclusion, Cr supplementation at a level of 1200 μg/kg diet can alleviate the negative effects of heat stress on egg production, egg quality, egg hatching and some plasma constituent of laying Japanese quail reared under Egyptian summer conditions.