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Effects of breeder age and pre-incubation storage of eggs on hatchability, time of hatch and relative organ weight of quail chicks at hatch
Abstract
Two thousand four hundred quail (Coturnix coturnix japonica) hatching eggs were used to determine the effects of breeder age and pre-incubation storage time on egg traits, hatching traits and the growth of some selected organs in newly hatched chicks. Eggs from two non-commercial flocks (aged 10 vs. 40 weeks) of the same strain were incubated. Eggs were stored for 4 or 14 days prior to incubation. All eggs were set in an experimental setter and incubated under uniform conditions for approximately 19 days (448 h). Fresh egg weight, chick weight and percentage yolk weight were significantly higher in eggs obtained from breeders at 40 weeks of age than from those of 10 weeks of age, whereas percentage albumen weight was significantly higher in eggs obtained from 10 wk old breeders. There were significant storage period x hen age interactions for water loss in chicks, early embryonic death, late embryonic death, deaths during internal and external pipping, and hatchability of fertile eggs. From 405 h to 441 h of incubation, the percentage of hatched chicks was influenced by the storage period x breeder age interaction. The jejunum length of chicks from 40 wk old breeders was longer when eggs were stored for 4 days compared to 14 days. At hatch, chick liver weight as a percentage of live weight was higher when eggs obtained from 10 wk old breeders were stored for 4 days compared to 14 days. It was concluded that the effects of extended storage time on hatching traits were different for eggs laid by young compared to old breeders.
Keywords: Hatchability; breeder age; egg storage; organ weights; quail
South African Journal of Animal Sciences Vol. 35 (2) 2005: pp.135-142