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Food, fibre and pharmaceuticals from animals
REVIEW (Open Access)

Nutrition, feeding and laying hen welfare

W. L. Bryden https://orcid.org/0000-0002-7187-4464 A C , X. Li https://orcid.org/0000-0003-3109-5789 A , I. Ruhnke https://orcid.org/0000-0001-5423-9306 B , D. Zhang A and S. Shini A
+ Author Affiliations
- Author Affiliations

A University of Queensland, School of Agriculture and Food Sciences, Gatton, Qld 4343, Australia.

B University of New England, School of Environmental and Rural Science, Armidale, NSW 2350, Australia.

C Corresponding author. Email: w.bryden@uq.edu.au

Animal Production Science 61(10) 893-914 https://doi.org/10.1071/AN20396
Submitted: 6 July 2020  Accepted: 9 September 2020   Published: 23 February 2021

Journal Compilation © CSIRO 2021 Open Access CC BY-NC-ND

Abstract

The relationship between nutrition and welfare is usually considered to be a direct result of supplying the hen with adequate quantities of feed and water. This simple notion of freedom from hunger and thirst belies the fact that nutrients play a pivotal role in the body’s response to challenges whether they relate to ambient temperature, gastrointestinal health, pathogen exposure, metabolic disorders, or social and mental stress. In all instances, maintaining homeostasis and allowing for physiologic response is dependent on an adequate and balanced nutrient supply. It is accepted that most laying hens are fed a complete diet, formulated commercially to provide the required nutrients for optimal health, egg production and welfare. In other words, the laying hen, irrespective of her housing, does not experience hunger or thirst. However, despite adequate nutrient and water supply, certain senarios can significantly affect and alter the nutrient requirements of the hen. Furthermore, the chemical composition and also the physical form of feed can significantly contribute to prevent or treat welfare and health conditions and is, therefore, a highly relevant tool to ensure and maintain an adequate welfare status. Therefore, this review takes a broader perspective of nutritional welfare and considers the nutrition of hens managed in different production systems in relation to nutritional physiology, gut microbiota, stress, metabolic disorders and feeding management.

Keywords: amino acid, calcium, diet, energy, gut health, gut microbiota, immunity, inflammation, metabolic disorder, nutritional physiology, pasture, phosphorus, stress.


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