Relationship of parents' age, hatching egg weight, and shell quality to day-old chick weight as influenced by oviposition time.
This study was conducted with 840 eggs from commercial breeder hens to determine relationship of parents' age, egg weight, and to oviposition time and shell quality and day-old chick weight. Results indicate that eggs laid in the afternoon were significantly smaller with significantly better shell quality than those laid in the morning (64.1 vs. 64.5 g and specific gravity of 1.077 vs. 1.074, respectively). Also, chicks from afternoon eggs tended to weigh significantly less than those from morning eggs. However, the egg weight: chick weight ratio was not significantly affected by oviposition time; it was the same for morning and afternoon eggs (70.7 vs. 70.1%). The linear relationships between egg weight, age, and chick weight or between egg weight and chick weight were strong (R2 = .78 to .91), but the associations between specific gravity and chick weight were weaker (R2 = .28 to .24). It was possible to use both parents' age and egg weight or egg weight alone to predict chick weight for chicks hatched from morning and afternoon eggs.
D000375:Aging; D000818:Animals; D001835:Body Weight; D002645:Chickens / Q000502:physiology*; D004528:Egg Shell; D005260:Female; D010058:Oviposition; D013997:Time Factors