The effect of age of broiler breeder and length of egg storage period on embryonic development and hatchability percentage [electronic resource].

Includes references.

The present study was carried out to investigate the influence of broiler breeder age and storage period on some embryonic parameters and chick weight' at hatch. Five¬ hundred and forty eggs were collected from 41 and 56 – week old Arbor Acres broiler breeder hens (270 eggs from each age). The eggs of each age were randomly distributed into three groups. The first group was set freshly in the setter of incubator, while, the other groups were stored for 7 or 14 days at 12° C and 85% relative humidity. The current results showed that embryo weight on the 17th day of incubation and chick's weight at hatch were lower when eggs brought from younger hens than older ones. On the other hand, the reverse results were observed in relative weight of embryo. However, eggs obtained from young hens had significantly higher fertility than eggs from old hens. At hatch, plasma glucose concentration and cardiac glycogen were higher, while, hepatic glycogen concentration was lower in chicks from young hens than those from old hens. On the other hand, parent age was not influenced by the previous parameters, on the 17th day of incubation. Skeletal muscle glycogen measured on the 17th day of incubation was higher in young hens than old ones. Fresh eggs and those stored for only seven days before incubation had greater absolute and relative embryonic weight than those stored for fourteen days. Plasma glucose concentration tended to decrease, while, hepatic glycogen and skeletal muscle glycogen concentration tended to decrease on the 17th day of incubation and at hatch with the increase in the storage period. However, cardiac glycogen concentration not affected by storage period on day 17 of incubation, but at hatch it was decreased by the increase of storage period.

Summary in Arabic.

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