الفهرس | Only 14 pages are availabe for public view |
Abstract The aim of this study was to determine the influence of genotype, age of layer breeder eggshell traits, egg quality, ultrastructure of eggshell during phases of hatching eggs (before, 10th , 17th day, of incubation and after hatch) and some physiological traits. In the project, breeder strains were used (Hy-line Brown and Hy-line White 36) with flock age (22, 33, 43 and 64weeks of age) during incubation stages (before hatch, 10, 17 day of incubation and after hatch). At any age, 130 egg from each genotype were examined. The results showed that the strain had a significant effect on body weight at hatch, chick yield, egg weight, egg length, egg width, shap index, specific gravity, albumen height, albumen weight, albumen %, yolk height, yolk diameter, yolk index, yolk weight, yolk %, yolk albumen ratio, wet shell weight, dry shell weight, Calcium % in serum and shell %. The breeder´s age affected body weight at hatch, chick yield, egg weight, egg length, egg width, shap index, specific gravity, albumen height, albumen weight, albumen %, yolk height, yolk diameter, yolk index, yolk weight, yolk %, yolk albumen ratio, wet shell weight, dry shell weight, Thymus weight (%) and shell %. The white strain eggshell had several ultrastructure defects ( late fusion, poor confluence and type B′s) with different ages of breeders compared with brown strain eggshell. In the same times, the brown eggshell had good ultrastructure features (early fusion and cuffing) compared with white eggshell counterparts. It could be observed that the genetic differences among layer breeder strains and age of breeders can affect the hatchery performance. |