Variance components and selection response for feather-pecking behavior in laying hens

Variance components and selection response for feather-pecking behavior in laying hens.

Variance components and selection response for feather pecking behavior were studied by analyzing the data from a divergent selection experiment. An investigation indicated that a Box-Cox transformation with power lambda = -0.2 made the data approximately normally distributed and gave the best fit for the model. Variance components and selection response were estimated using Bayesian analysis w...

Severe feather-pecking in free-range ISA Brown laying hens

................................................................................................................................ 37 CHAPTER 1: General Introduction ......................................................................................... 44 TYPES OF BIRD-TO-BIRD PECKING .................................................................................. 47 HOUSING SYSTEMS ...........

Controlling Feather Pecking & Cannibalism in Laying Hens without Beak Trimming

Genetic and phenotypic correlations between feather pecking behavior, stress response, immune response, and egg quality traits in laying hens.

The objective of the current study was to estimate genetic and phenotypic correlations among feather pecking (FP) behavior and stress response, immune response, and egg quality parameters. These traits have been measured in an F2 cross, coming from a cross between a high and a low FP line of laying hens. Heritabilities (h2) of stress response (32 wk), primary immune response to keyhole limpet h...

Relationship between feather pecking and ground pecking in laying hens and the effect of group size.

The aim of this experiment was to study the relationship between feather pecking and ground pecking in laying hens and the effect of group size on feather pecking behaviour. Hisex White hens were kept in floor pens in group sizes of 15, 30, 60 and 120 birds, each with four replicates. Behavioural observations were performed at four different ages and focused on the number of feather pecks and a...