Interaction between oviposition time, age, and environmental temperature and egg quality traits in laying hens and broiler breeders

An experiment with laying hens and broiler breeders of two ages (young 22 vs. 36 weeks, old 83 vs. 64 weeks) and at temperatures of 20 and 28°C was carried out to evaluate the interactions between oviposition time (7:30; 11:30, and 15:30 h), age, and temperature on the one hand and egg quality on the other. A significant interaction (P ≤ 0.011) was determined in oviposition time. The highest number (25.8%) of eggs was laid at 7:30 h by young laying hens kept at 20°C and the lowest (3.7%) by young layers at 15:30 h kept in the same temperature. Time of oviposition was delayed by age and a higher temperature. Egg weight was significantly influenced by production type (P ≤ 0.001; 60.5 vs. 68.1 g), age (P ≤ 0.001; 59.4 vs. 69.3 g), oviposition (P ≤ 0.001; 66.5, 63.7, 62.8 g), and temperature (P ≤ 0.022; 65.1 vs. 63.6 g). The significant threeway interaction of age, oviposition, and temperature in Haugh unit score (P ≤ 0.013) and four-way interaction of production type, age, oviposition, and temperature (P ≤ 0.05) in specific gravity show that rather than by a single factor the valuable characteristics of egg quality are considerably affected by a combination of factors.