Fearfulness in commercial laying hens: a meta-analysis comparing brown and white egg layers.

ABSTRACT: High fearfulness in commercial laying hens can negatively affect production parameters and animal welfare. Brown and white egg layers differ in several behavioral characteristics, though reported differences in fearfulness are inconsistent. A meta-analysis was conducted to determine whether there are systematic differences in measures of fearfulness between brown and white layers. Twenty-three studies that examined either 1 or both of 2 behavioral tests were included: tonic immobility (TI) (longer duration = higher fearfulness, 16 studies) and novel object (NO) test (lower approach rate = higher fearfulness, 11 studies). The 2 tests were analyzed separately. TI analyses: A generalized linear mixed effect model (GLMM) with a lognormal distribution was fitted to describe the data with experi

SUBMITTER: Rentsch AK 

PROVIDER: S-EPMC10123257 | biostudies-literature | 2023 Jun

REPOSITORIES: biostudies-literature