Effects of Rearing Aviary Style and Genetic Strain on the Locomotion and Musculoskeletal Characteristics of Layer Pullets

摘要

Consumer trends have led to the popularisation of eggs from hens housed in non-cage systems. Aviaries are common non-cage systems that consist of multi-tiered structures with essential resources located within. Being a ground-dwelling species, laying hens must learn when they are young to navigate aviaries, and develop the strength to do so. However, there are different styles of aviaries with varying degrees of structural complexity in which young laying hens (pullets) are reared. This study examined the differences in locomotion and musculoskeletal characteristics of white- and brown-feathered strains of pullets housed in three different styles of rearing aviaries (low, moderate, and high structural complexity) on commercial farms. Pullets in the most complex system spent the most time locomoting, and white-feathered strains in the highly complex systems performed the most jumps and flights. While there were no differences in muscle weights between aviary styles, white-feathered strains, and pullets in the most complex aviary had stronger leg bones than brown-feathered strains and pullets in the least complex system. These results indicate that the style of the aviary in which pullets are reared can affect their bone strength, most likely through differences in the load-bearing exercises performed.