Laying hens behave as omnivores with poultry meal included in their diet

Abstract

This study was conducted to determine egg yield performance and quality, animal partiality to poultry meal, and consumer preferences for eggs produced by various feeding methods. A total of 72 Nick Brown laying hens, aged 22 weeks, were offered three feeding methods with 24 replicates per treatment and one hen per experimental unit. These methods consisted of i) vegetarian (no poultry meal), ii) omnivorous (5% poultry meal), and iii) a choice between vegetarian and omnivorous. Feed and water were provided ad libitum. The study lasted for 10 weeks. Feeding methods did not affect feed intake, feed conversion ratio, egg yield, and egg quality. However, they affected the malondialdehyde (MDA) value of eggs on the 42nd day of storage significantly (P <0.05). The highest MDA value was obtained from the eggs of ‘omnivorous’ hens. More hens (51.4%) in the choice group preferred omnivorous feed to ‘vegetarian’. Panellists found organoleptic differences among sample eggs from hens subjected to various feeding methods. They reported that the eggs obtained from vegetarian hens were preferable. The conclusions were that i) no feeding method changed egg yield performance and quality, ii) omnivorous feeding shortened the shelf-life of eggs, iii) hens with a choice of feed did not reject the omnivorous diet, but increased their intake, and iv) the panellists disliked eggs from the omnivorous hens. Finally, these preferences should be considered in legislation for poultry feeding and animal husbandry.