The effect of plumage colour and serotonin transporter gene polymorphism on feather pecking behaviour in laying hens.

Güney A., Özkan S. , Krause E., Phi Van L., Kjaer J. B.

XVth EUROPEAN POULTRY CONFERENCE, Dubrovnik, Croatia, 17 - 21 September 2018, pp.460

  • Publication Type: Conference Paper / Summary Text
  • City: Dubrovnik
  • Country: Croatia
  • Page Numbers: pp.460


The effect of plumage colour and serotonin transporter gene

polymorphisms on feather pecking behaviour in laying hens

Abstract ID: 157

A. Güney Ertan1, S. Özkan1, E. Krause2, L. Phi van2, J. B. Kjaer2

1Ege University, Faculty of Agriculture, Department of Animal Science, İzmir, Turkey,

2Friedrich-Loeffler-Institute, Department of Animal Husbandry and Behaviour, Celle, Germany

Feather pecking in laying hens is a serious welfare problem and the motivation for

this behaviour is still unclear. Only few studies focused on the role of the victims and

it seems that some birds attract more feather pecking than others. In the present

study, feather pecking was recorded in 216 hens from three experimental lines bred

from a commercial medium heavy brown hybrid. These lines differed in genotype of

a single nucleotide polymorphism (SNP) in the serotonin transporter (SERT) gene,

being wildtype (W/W), mutants (D/D) or heterozygotes (W/D). Through several years of

crossings of this commercial hybrid, however, a range of colour phenotypes had emerged

and these were categorized in beige (white with some reddish spots, n=31), brown

(n=100), grey (white with dark grey stripes, n=19) and white (n=66). The number of

feather pecks (severe or gentle) and aggressive pecks given and received were recorded

on an individual basis twice a day (1 h/morning and 1 h/afternoon) for 23 days at the age

of 32 to 35 weeks. Plumage condition was scored as well. Severe feather pecking was the

predominant type of pecking (on average 7.8, 1.3 and 3.6 severe, gentle and aggressive

pecks given per hen, respectively) and therefore only severe feather pecking is presented

here. Colour morphology did not affect performance of severe feather pecking but

genotype did. W/D hens pecked more and lsmeans for pecking per bird were 12.6, 8.1

and 3.5 for W/D, W/W and D/D hens, respectively (P<0.001). There were significant

effects of colour morph as well as genotype on number of pecks received. Beige (3.26)

and grey hens (2.47) received more pecks as compared with brown (1.66) and white

(1.24) hens (P < 0.05). WW hens received more pecks (1.13, 1.63 and 2.77 for D/D, W/D

and W/W, respectively) (P < 0.001). Plumage condition was not affected by genotype

but colour morph. Brown hens had the worst scores (ChiSquare=81.4, P<0.001). In

conclusion, beige and grey plumage colour attract more pecking than white and brown

in contrast to earlier reports. This suggests that plumage with a combination of colours

(speckled) attracts more pecking than even colours. On the other hand, the darkest hens

had the most feather damage. Further, it was a new finding that hens carrying the W/D

genotype of the SERT gene polymorphism pecked more and that hens carrying the W/W

genotype received more severe feather pecking, and this needs further investigation.

Keywords: Feather pecking, Genetic crossing, Plumage colour, Plumage condition, Welfare