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

H Çayan,A Şahin

doi:10.4314/sajas.v51i3.1

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.

Highlights

The hens were divided into three groups with equal bodyweight and egg production. These groups were allocated to three feeding methods, namely i) vegetarian, ii) omnivorous (5% poultry meal), and iii) a choice between these diets
The tendencies of increases in egg production and bodyweight in omnivorous groups may be because the chemical composition of poultry meal is similar to their own body composition
These increases may be because of the lower need for metabolic processing of nutrients in poultry meal compared with vegetable ingredients

Summary

Introduction

In nature and in extensive production systems, chickens eat small seeds, cereals, herbs and leaves, grubs, insects, and even small mammals. Chickens often dig to obtain adult insects and larvae and seed. When chickens are given the opportunity, they make their own diet according to their physiological and metabolic needs (Forbes, 1995; Sahin, 1999). In human-driven production systems, chickens need help in balancing their diets in terms of metabolic and physiological needs. Protein sources of vegetable and animal origin (e.g. by-products) are used to meet these needs

Methods

Results

Conclusion