Effect of Layer Breeder Strain and Age on Tibia Bone Characteristics of Chicks.

Abstract

This experiment was designed to study the effect of layer breeder strain and age of chickens on absolute and relative chick weight, tibia bone characteristics, percentage of calcium and phosphorus of tibia bone and body weights. The present results showed that absolute and relative chick weight was highly significantly affected by strain and breeder age. The brown breeder hens produced heavier chick weight compared to the white ones. Tibia bone weight, tibia width, tibia thickness and tibia strength were highly significantly affected by strain, whereas the brown chicks recorded significantly higher values compared to the white ones. Concerning age effect, it could be noticed that all tibia bone characteristics of chicks except tibia breaking strength were highly significantly affected by breeder age, the mid age (at 47 weeks) was characterized with heaviest tibia and longest and thickness. Percentage of calcium in tibia bone did not significantly affected by strain, breeder age and their interaction. Strain had insignificant effect on phosphorus percentage, while breeder age had significant effect of phosphorus percentage. In general, the tibia bone of brown chicks had higher calcium and phosphorus percentages than that of white ones. Chemical analysis decreased as age advanced. Body weight data manifested that brown strain had significantly heavier body weight compared to the white ones. Weight increased gradually as age increased.