Plumage condition in laying hens: Genetic parameters for direct and indirect effects in two purebred layer lines

T. Brinker, P. Bijma, J. Visscher, T.B. Rodenburg, E.D. Ellen

Research output: Contribution to journalArticleAcademicpeer-review

13 Citations (Scopus)

Abstract

Background: Feather pecking is a major welfare issue in laying hen industry that leads to mortality. Due to a ban on conventional cages in the EU and on beak trimming in some countries of the EU, feather pecking will become an even bigger problem. Its severity depends both on the victim receiving pecking and on its group mates inflicting pecking (indirect effects), which together determine plumage condition of the victim. Plumage condition may depend, therefore, on both the direct genetic effect of an individual itself and on the indirect genetic effects of its group mates. Here, we present estimated genetic parameters for direct and indirect effects on plumage condition of different body regions in two purebred layer lines, and estimates of genetic correlations between body regions. Methods: Feather condition scores (FCS) were recorded at 40 weeks of age for neck, back, rump and belly and these four scores were added-up into a total FCS. A classical animal model and a direct–indirect effects model were used to estimate genetic parameters for FCS. In addition, a bivariate model with mortality (0/1) was used to account for mortality before recording FCS. Due to mortality during the first 23 weeks of laying, 5363 (for W1) and 5089 (for WB) FCS records were available. Results: Total heritable variance for FCS ranged from 1.5% to 9.8% and from 9.8% to 53.6% when estimated respectively with the classical animal and the direct–indirect effects model. The direct–indirect effects model had a significantly higher likelihood. In both lines, 70% to 94% of the estimated total heritable variation in FCS was due to indirect effects. Using bivariate analysis of FCS and mortality did not affect estimates of genetic parameters. Genetic correlations were high between adjacent regions for FCS on neck, back, and rump but moderate to low for belly with other regions. Conclusion: Our results show that 70% to 94% of the heritable variation in FCS relates to indirect effects, indicating that methods of genetic selection that include indirect genetic effects offer perspectives to improve plumage condition in laying hens. This, in turn could reduce a major welfare problem.
Original languageEnglish
Article number33
Number of pages10
JournalGenetics, Selection, Evolution
Volume46
DOIs
Publication statusPublished - 2014

Fingerprint

Feathers
plumage
feather
purebreds
feathers
laying hens
feather pecking
mortality
Mortality
pecking
body regions
rump
Body Regions
genetic correlation
neck
beak trimming
effect
parameter
Neck
Beak

Keywords

  • feather pecking behavior
  • multilevel selection
  • social interactions
  • breeding programs
  • production traits
  • ground-pecking
  • animal-welfare
  • gallus-gallus
  • flock size
  • cannibalism

Cite this

@article{6819374188194173b6520d1554ab392d,
title = "Plumage condition in laying hens: Genetic parameters for direct and indirect effects in two purebred layer lines",
abstract = "Background: Feather pecking is a major welfare issue in laying hen industry that leads to mortality. Due to a ban on conventional cages in the EU and on beak trimming in some countries of the EU, feather pecking will become an even bigger problem. Its severity depends both on the victim receiving pecking and on its group mates inflicting pecking (indirect effects), which together determine plumage condition of the victim. Plumage condition may depend, therefore, on both the direct genetic effect of an individual itself and on the indirect genetic effects of its group mates. Here, we present estimated genetic parameters for direct and indirect effects on plumage condition of different body regions in two purebred layer lines, and estimates of genetic correlations between body regions. Methods: Feather condition scores (FCS) were recorded at 40 weeks of age for neck, back, rump and belly and these four scores were added-up into a total FCS. A classical animal model and a direct–indirect effects model were used to estimate genetic parameters for FCS. In addition, a bivariate model with mortality (0/1) was used to account for mortality before recording FCS. Due to mortality during the first 23 weeks of laying, 5363 (for W1) and 5089 (for WB) FCS records were available. Results: Total heritable variance for FCS ranged from 1.5{\%} to 9.8{\%} and from 9.8{\%} to 53.6{\%} when estimated respectively with the classical animal and the direct–indirect effects model. The direct–indirect effects model had a significantly higher likelihood. In both lines, 70{\%} to 94{\%} of the estimated total heritable variation in FCS was due to indirect effects. Using bivariate analysis of FCS and mortality did not affect estimates of genetic parameters. Genetic correlations were high between adjacent regions for FCS on neck, back, and rump but moderate to low for belly with other regions. Conclusion: Our results show that 70{\%} to 94{\%} of the heritable variation in FCS relates to indirect effects, indicating that methods of genetic selection that include indirect genetic effects offer perspectives to improve plumage condition in laying hens. This, in turn could reduce a major welfare problem.",
keywords = "feather pecking behavior, multilevel selection, social interactions, breeding programs, production traits, ground-pecking, animal-welfare, gallus-gallus, flock size, cannibalism",
author = "T. Brinker and P. Bijma and J. Visscher and T.B. Rodenburg and E.D. Ellen",
year = "2014",
doi = "10.1186/1297-9686-46-33",
language = "English",
volume = "46",
journal = "Genetics, Selection, Evolution",
issn = "0999-193X",
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Plumage condition in laying hens: Genetic parameters for direct and indirect effects in two purebred layer lines. / Brinker, T.; Bijma, P.; Visscher, J.; Rodenburg, T.B.; Ellen, E.D.

In: Genetics, Selection, Evolution, Vol. 46, 33, 2014.

Research output: Contribution to journalArticleAcademicpeer-review

TY - JOUR

T1 - Plumage condition in laying hens: Genetic parameters for direct and indirect effects in two purebred layer lines

AU - Brinker, T.

AU - Bijma, P.

AU - Visscher, J.

AU - Rodenburg, T.B.

AU - Ellen, E.D.

PY - 2014

Y1 - 2014

N2 - Background: Feather pecking is a major welfare issue in laying hen industry that leads to mortality. Due to a ban on conventional cages in the EU and on beak trimming in some countries of the EU, feather pecking will become an even bigger problem. Its severity depends both on the victim receiving pecking and on its group mates inflicting pecking (indirect effects), which together determine plumage condition of the victim. Plumage condition may depend, therefore, on both the direct genetic effect of an individual itself and on the indirect genetic effects of its group mates. Here, we present estimated genetic parameters for direct and indirect effects on plumage condition of different body regions in two purebred layer lines, and estimates of genetic correlations between body regions. Methods: Feather condition scores (FCS) were recorded at 40 weeks of age for neck, back, rump and belly and these four scores were added-up into a total FCS. A classical animal model and a direct–indirect effects model were used to estimate genetic parameters for FCS. In addition, a bivariate model with mortality (0/1) was used to account for mortality before recording FCS. Due to mortality during the first 23 weeks of laying, 5363 (for W1) and 5089 (for WB) FCS records were available. Results: Total heritable variance for FCS ranged from 1.5% to 9.8% and from 9.8% to 53.6% when estimated respectively with the classical animal and the direct–indirect effects model. The direct–indirect effects model had a significantly higher likelihood. In both lines, 70% to 94% of the estimated total heritable variation in FCS was due to indirect effects. Using bivariate analysis of FCS and mortality did not affect estimates of genetic parameters. Genetic correlations were high between adjacent regions for FCS on neck, back, and rump but moderate to low for belly with other regions. Conclusion: Our results show that 70% to 94% of the heritable variation in FCS relates to indirect effects, indicating that methods of genetic selection that include indirect genetic effects offer perspectives to improve plumage condition in laying hens. This, in turn could reduce a major welfare problem.

AB - Background: Feather pecking is a major welfare issue in laying hen industry that leads to mortality. Due to a ban on conventional cages in the EU and on beak trimming in some countries of the EU, feather pecking will become an even bigger problem. Its severity depends both on the victim receiving pecking and on its group mates inflicting pecking (indirect effects), which together determine plumage condition of the victim. Plumage condition may depend, therefore, on both the direct genetic effect of an individual itself and on the indirect genetic effects of its group mates. Here, we present estimated genetic parameters for direct and indirect effects on plumage condition of different body regions in two purebred layer lines, and estimates of genetic correlations between body regions. Methods: Feather condition scores (FCS) were recorded at 40 weeks of age for neck, back, rump and belly and these four scores were added-up into a total FCS. A classical animal model and a direct–indirect effects model were used to estimate genetic parameters for FCS. In addition, a bivariate model with mortality (0/1) was used to account for mortality before recording FCS. Due to mortality during the first 23 weeks of laying, 5363 (for W1) and 5089 (for WB) FCS records were available. Results: Total heritable variance for FCS ranged from 1.5% to 9.8% and from 9.8% to 53.6% when estimated respectively with the classical animal and the direct–indirect effects model. The direct–indirect effects model had a significantly higher likelihood. In both lines, 70% to 94% of the estimated total heritable variation in FCS was due to indirect effects. Using bivariate analysis of FCS and mortality did not affect estimates of genetic parameters. Genetic correlations were high between adjacent regions for FCS on neck, back, and rump but moderate to low for belly with other regions. Conclusion: Our results show that 70% to 94% of the heritable variation in FCS relates to indirect effects, indicating that methods of genetic selection that include indirect genetic effects offer perspectives to improve plumage condition in laying hens. This, in turn could reduce a major welfare problem.

KW - feather pecking behavior

KW - multilevel selection

KW - social interactions

KW - breeding programs

KW - production traits

KW - ground-pecking

KW - animal-welfare

KW - gallus-gallus

KW - flock size

KW - cannibalism

U2 - 10.1186/1297-9686-46-33

DO - 10.1186/1297-9686-46-33

M3 - Article

VL - 46

JO - Genetics, Selection, Evolution

JF - Genetics, Selection, Evolution

SN - 0999-193X

M1 - 33

ER -