The Effect of Chromium Supplementation on Egg Production, Egg Quality and Some Serum Parameters in Laying Hens

Abstract: The effects of chromium (Cr) on egg production, egg quality, egg yolk cholesterol level and selected serum parameters of laying hens were investigated. Sixty 16-wk-old Hyline White 77 strain were randomly assigned to two groups of 30 hens each and fed either a basal diet or basal diet supplemented with 20 ppm Cr (CrCl3.6H2O). Egg and blood samples were collected at monthly intervals after the egg production reached peak level. Sera were analysed for chromium, calcium, inorganic phosphorus, magnesium, triglycerides and total cholesterol. Eggs were examined for interior or exterior quality and for yolk cholesterol content. Chromium supplementation resulted in a 1.88 % reduction in feed consumption and 4.28 % improvement in the efficiency of feed utilisation. Chromium had no effect on live weight change, overall mean egg production, egg weight, specific gravity, shape index, shell thickness and Haugh unit, but increased shell breaking strength, albumen and egg yolk index values were noted. Supplemental chromium had no significant effect on serum phosphorus, while it resulted in increases in calcium and magnesium concentrations at first sampling. Serum total cholesterol concentrations slightly decreased while triglyceride levels significantly decreased. Significant reductions were observed in yolk cholesterol content in chromium supplemented group at weeks 36 and 40 (p<0.001). The results of the experiment indicated that chromium supplementation to the diet of layers may be of practical value due to the slight reduction in feed consumption and improvement in efficiency of feed utilisation and reduced egg cholesterol content without any adverse effec