Feather pecking phenotype affects behavioural responses of laying hens

Research output: Chapter in Book/Report/Conference proceedingAbstract


Feather pecking (FP) is a major welfare and economic issue in the egg production industry. It involves hens pecking and pulling at feathers of conspecics, thereby negatively aecting welfare. Behavioural characteristics, such as fearfulness, have been related to FP. Although many studies have identied dierences in fearfulness between lines that dier in FP, the relationship between actual FP behaviour (i.e. FP phenotypes) and fearfulness is not well understood. erefore, we compared responses of birds with diering FP phenotypes to several behavioural tests at young and adult ages. We used birds from a genetic line selected for high feather pecking. FP phenotypes of individual birds were identied via FP observations at 3-4, 12-13, 15-16 and 28-29 weeks of age. e total number of severe feather pecks (SFP) given and received over two subsequent weeks was used to categorize birds as feather peckers (P, SFP given >1), feather pecker-victims (P-V, SFP given and received >1), victims (V, SFP received >1) or neutrals (N, SFP given and received 0 or 1) at each age point. Birds were tested individually in a novel environment (NE) test at 4 weeks of age, an open eld (OF) test at 15 weeks of age and a tonic immobility (TI) test at 13 and 28 weeks of age. Experimenters were blinded to the phenotypes. Data were analysed using linear mixed models, with phenotype and batch as xed factors and pen as a random factor. Test time was added as a xed eect for the NE and OF test. Experimenter was added as a xed eect for the NE and TI test. Testing order was included as a xed eect for the TI test. Phenotype eects were tested for each behavioural test and age separately using the most recent FP phenotype categorization. FP phenotype aected the number of ight attempts (F3, 119=3.18, P<0.05) during the NE test, where victims showed more ight attempts compared to neutrals (V=2.3 vs n=1.6; P<0.05) and tended to show fewer ight attempts compared to feather peckers (V=2.3 vs P=2.7; P<0.1). FP phenotype further tended to aect step frequency (F3, 75=2.64, P<0.1) during the OF test, where feather peckers tended to walk more compared to neutrals (P=24.6 vs n=15.7; P<0.1). No FP phenotype eects were found for the TI test. Feather peckers tended to show more active responses (i.e. tended to show more ight attempts compared to victims and tended to walk more compared to neutrals), which could suggest lower fearfulness, compared to victims at 4 weeks of age and compared to neutrals at 15 weeks of age. ese ndings give rst indications that FP phenotypes seem to dier in fearfulness. It should be noted that we only found dierences in the NE and OF test, where behavioural responses could also be related to activity or coping style. Further research is needed to identify whether FP phenotypes dier in activity and whether they can be classied into dierent coping styles.
Original languageEnglish
Title of host publicationProceedings of the 52nd Congress of the International Society for Applied Ethology
Subtitle of host publicationEthology for health and welfare
EditorsMichael Cockram, Tarjei Tennessen, Luis Bate, Renée Bergeron, Sylvie Cloutier, Andrew Fisher, Maria Hötzel
Place of PublicationWageningen, The Netherlands
PublisherWageningen Academic Publishers
ISBN (Electronic)9789086868704
ISBN (Print)9789086863228
Publication statusPublished - 2018
EventISAE 2018: 52nd Congress of the International Society for Applied Ethology - Charlottetown, Canada
Duration: 30 Jul 20183 Aug 2018


OtherISAE 2018


Dive into the research topics of 'Feather pecking phenotype affects behavioural responses of laying hens'. Together they form a unique fingerprint.

Cite this