Genetics

News 55 comments

Genes and their role in feather pecking explored

Studies into mortality due to feather pecking have in the past pointed to genes as playing a substantial role in cannibalism.

Now, the Animal Breeding and Genomics of Wageningen University and Research and Hendrix Genetics have investigated the genomic regions associated with survival time in laying hens.

Feather pecking main reason for reduced survival

Survival is an important welfare and economic trait in laying hens and feather pecking behaviour is the main reason for reduced survival. Survival is a socially affected trait, because the survival time of a hen depends not only on her own ability to avoid being pecked but also on the pecking behaviour of her group mates.

Genome-wide association study

Scientists know that direct and social genetic effects contribute about 50% of the total heritable variation in laying hens with intact beaks. But they did not know the genes responsible for the direct and social genetic effects.

As a result, they carried out a genome-wide association study using genotype and phenotype data on three crossbred White Leghorn layer lines provided by Hendrix. Hens had intact beaks and were kept with sibs in traditional 5-bird battery cages in Kitchener, Canada.

Survival is an important welfare and economic trait in laying hens and feather pecking behaviour is the main reason for reduced survival.  - Photo: Henk Riswick
Survival is an important welfare and economic trait in laying hens and feather pecking behaviour is the main reason for reduced survival. - Photo: Henk Riswick

Single-nucleotide polymorphisms

Single-nucleotide polymorphisms (SNPs) effects were estimated one by one, for both direct and indirect effects. The results showed several SNP’s associated with direct effects on survival time, but none with indirect effects. In one of the crosses, a clear direct SNP-effect was found on chromosome 2, close to the GAPA receptor gene (GABBR2).

In another cross, the same region was associated with the social effect, although not significant. The favourable allele had a positive effect on both the survival time of the individual and its group mates.

The GABA receptor gene

The GABA receptor gene plays an important role in the regulation of neurotransmitters in the brain. Several studies have shown that GABA plays a role in psychological and behavioural stress in many species and is associated with behavioural disorders.

The results have been published in Genetics Selection Evolution.

55 comments

  • gubbi lokanath

    Points to ponder : 1. Have the flocks been evaluated for the nutrient metabolic status-anabolism and catabolism- w.r.t. calcium and other minerals?
    2. Is this relevant and persistent to layer birds only and not broiler birds ?
    3. It has been well proved since a few decades of the cannibolistic/agonistic behaviour genetically without reference to gene mapping and identity.
    4. Does the behaviour show varied levelsof cannibolism at different stages of early growth, grower phase and adult phase and if so,to what extent of genetic variability and control is estimated in the same flock subjected to experimentation ?
    Overall, a good study, which will help to reduce morbidity and mortality in future to improve economics.
    Thanks.
    lnathgubbi

  • Scott Porter

    It is really great that we do try our best to study on what is really best for this fowls as they are becoming or even is one of the most important meat these days.

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

  • Comment deleted by a moderator

Load more comments (51)

Commenting is closed.