Authors : C.H. Kim, I.K. Paik, D.Y. Kil and M.B. Chang
Abstract: The objective of this experiment was to investigate the effect of dietary Magnesium (Mg) concentrations on productive performance and eggshell quality of laying hens. A total of 800 Hy-Line Brown laying hens (46 weeks old) were randomly allotted to 1 of 5 dietary treatments with 4 replicates per treatment. A commercial-type basal diet (1.7 g kg-1 Mg) was prepared and 4 additional diets were formulated to contain 2.3, 3.0, 3.5 or 4.2 g kg-1 Mg in diets by adding 1.0, 2.0, 3.0 or 4.0 g of MgO (600 g kg-1 Mg) to the basal diet. The diets were fed to hens as ad libitum basis for 6 weeks. Results indicated that increasing concentrations of Mg in diets increased Mg concentrations in eggshells (linear and quadratic, p<0.05). Increasing concentrations of Mg in diets increased eggshell strength (quadratic, p<0.05) and eggshell thickness (linear, p<0.05) but decreased Hunter a* values for eggshell (linear, p<0.01). Hen-day egg production, feed intake, feed conversion ratio, egg weight and Haugh unit were not affected by Mg concentrations in diets. In conclusion, feeding diets containing increasing concentrations of Mg up to 4.2 g kg-1 to laying hens improves eggshell strength and eggshell thickness but has no effects on productive performance of laying hens.
C.H. Kim, I.K. Paik, D.Y. Kil and M.B. Chang, 2013. Effects of Dietary Magnesium Concentrations on Performance and Eggshell Quality of Laying Hens. Journal of Animal and Veterinary Advances, 12: 104-107.