Effects of Dietary Composite Bakery Waste on Productive Performance and Egg Quality Traits of Laying Hens in a Temperate Environment

Abstract

Introduction: High prices of traditional feedstuffs in developing countries, coupled with climate change that affects crop growth and yields, lead to shortages of conventional feeds. The current study aimed to determine the effects of different levels of composite bakery waste (CBW) as a replacement for maize on the productive performance and egg quality of laying hens in a temperate environment (-2°C to 20.3°C).
Materials and methods: A total of 150 laying hens aged 26 weeks, with an average body weight of 1.704 kilograms, were randomly allocated to five treatment groups, with three replicates of ten chickens each. The CBW was air-dried, ground, and analyzed for proximate composition, then replaced with maize in laying hens' diets at levels of 0% (T1), 5% (T2), 10% (T3), 15% (T4), and 20% (T5). The feeding trial duration was 49 days. Productive performance, such as body weight, mortality, and egg quality indices, including egg weight, shell weight, shell thickness, yolk height, yolk index, yolk color, albumen length, albumen width, albumen height, albumen weight, albumen index, and Haugh unit of the experimental laying hens, was determined at alternate weeks, except hen-day egg production which was recorded daily.
Results: The CBW contained 93.17% dry matter, 5.67% crude protein, 0.24% crude fiber, 0.31% ether extract, 83.30% nitrogen-free extract, 0.29% calcium, 0.53% phosphorus, and 3192.43 kcal/kg metabolizable energy. Dietary CBW had no significant effect on final body weight, hen-day egg production, and mortality. Dietary CBW demonstrated a significant positive correlation with eggshell thickness across all treatment groups. Adding CBW demonstrated a positive, statistically significant correlation with albumen length in T4 compared to other groups. However, the inclusion of CBW did not demonstrate significant effects on internal egg traits, specifically yolk length, yolk height, yolk index, yolk color, albumen width, albumen height, albumen weight, and albumen index, across all treatment groups.
Conclusion: The present results demonstrated that CBW could replace up to 20% of maize, increased shell thickness, and had no detrimental impact on productive performance or external and internal egg quality, except for shell thickness and albumen length.