Assessment of Egg Quality Across Seasons, Storage Durations, and Temperatures in Commercial Laying Hens

Egg quality plays a crucial role in determining shelf life, consumer acceptability, and economic value in commercial egg production systems. This study evaluated the effects of season, storage temperature, and duration on internal and external egg quality. A total of 256 freshly laid eggs were collected during winter and spring, and stored at four temperatures (0 °C, 10 °C, 20 °C, and 30 °C) for 0, 10, 20, and 30 days. The experimental design was a 2 × 4 × 4 factorial design (season × temperature × duration), with 128 eggs collected each in both seasons. Each treatment combination included 8 eggs (2 eggs × 4 replicates). External quality (egg weight and shell thickness) and internal quality (yolk and albumen height, width, pH, Haugh units, and yolk colour) parameters were evaluated at 10-day intervals. Egg weight significantly decreased (p < 0.05) from 67.67 g on Day 0 to 59.39 g on Day 30. Similarly, shell thickness decreased (p < 0.05) from 40.00 mm to 36.00 mm over the same period. Yolk pH increased from 6.68 to 7.16 (p < 0.05), and albumen pH rose (p < 0.05) from 7.30 to 7.60, particularly at higher storage temperatures (20 °C and 30 °C). Yolk and albumen heights decreased significantly (p < 0.05), from 2.03 cm to 1.23 cm and 6.65 cm to 3.88 cm, respectively, indicating structural degradation. Yolk width increased from 2.58 cm to 3.49 cm (p > 0.05), and albumen width expanded (p < 0.05) from 5.33 cm to 9.21 cm, with a notably greater spread observed at 30 °C (14.68 cm). Haugh unit values declined markedly from 98.46 to 60.00 over 30 days (p < 0.05), indicating a significant deterioration in internal egg quality. Seasonal effects were also evident: spring eggs had greater shell thickness (40.60 mm vs. 38.45 mm in winter; p = 0.01) and brighter yolk colour, whereas winter eggs had higher yolk pH values (6.47 vs. 6.28; p = 0.009), and superior yolk and albumen heights. These findings indicate that storage beyond 10 days, particularly above 20 °C, compromises egg quality and that seasonality significantly affects multiple quality parameters. Cold storage and seasonally optimized management strategies are recommended to preserve egg integrity and marketability in commercial poultry systems.