title: Brain monoamine levels and behaviour of young and adult chickens genetically selected on feather pecking.
abstract: Severe feather pecking (SFP) in chickens is a detrimental behaviour with possibly neurochemical deficits at its base. Recent neurological studies depicted conflicting results on the role of serotonin (5-hydroxytryptamine, 5-HT) and dopamine (DA) in the development and display of feather pecking. We studied brain monoamine levels and behaviour in domestic chickens divergently genetically selected on feather pecking behaviour, the Low Feather Pecking (LFP) and High Feather Pecking (HFP) lines, both at a young age and when adult, to elucidate the role of 5-HT and DA in feather pecking. Also pecking behaviour and the behavioural response to challenging test situations was determined. At 8 weeks of age, HFP had lower 5-HT and DA turnover in several brain areas than LFP, whereas these differences had disappeared or were even reversed at 25 weeks of age. Line differences in central monoamine activity were found both in emotion-regulating and motor-regulating areas. As expected from previous generations, HFP exceeded LFP in most types of pecking at other birds, including severe feather pecking. Furthermore, HFP responded more actively in most behavioural tests conducted, and seem more impulsive or (hyper)active in their way of coping with challenges. This paper shows different developmental trajectories of the neurochemical systems (5-HT and DA) for chickens divergently selected on feather pecking behaviour, and a remarkable reversion of differences in monoamine activity at a later stage of life. Whether this is a cause or consequence of SFP needs further investigation.
authors.affiliation: Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Utrecht, the Netherlands.
authors.forename: M S
authors.initials: MS
authors.lastname: Kops
authors.affiliation: Friederich Loeffler Institut, Institute for Animal Welfare and Animal Husbandry, Celle, Germany.
authors.forename: J B
authors.initials: JB
authors.lastname: Kjaer
authors.affiliation: Department of Psychology, Ruhr-University of Bochum, Bochum, Germany.
authors.forename: O
authors.initials: O
authors.lastname: Güntürkün
authors.affiliation: Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Utrecht, the Netherlands.
authors.forename: K G C
authors.initials: KGC
authors.lastname: Westphal
authors.affiliation: Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Utrecht, the Netherlands.
authors.forename: G A H
authors.initials: GAH
authors.lastname: Korte-Bouws
authors.affiliation: Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Utrecht, the Netherlands.
authors.forename: B
authors.initials: B
authors.lastname: Olivier
authors.affiliation: Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Utrecht, the Netherlands.
authors.forename: S M
authors.initials: SM
authors.lastname: Korte
authors.affiliation: Adaptation Physiology Group, Wageningen University, Wageningen, the Netherlands. Electronic address: Liesbeth.Bolhuis@wur.nl.
authors.forename: J E
authors.initials: JE
authors.lastname: Bolhuis
mesh_terms: D000818:Animals; D015306:Biogenic Monoamines / Q000378:metabolism*; D001921:Brain / Q000254:growth & development* / Q000378:metabolism*; D002645:Chickens; D002851:Chromatography, High Pressure Liquid; D005241:Feathers; D005260:Female; D011581:Psychological Tests; D013045:Species Specificity; D013239:Stereotyped Behavior / Q000502:physiology*
chemical_list: D015306:Biogenic Monoamines
keywords: Brain monoamines; Chicken; Development; Dopamine; Genetic selection; Hyperactivity; Laying hen; Poultry welfare; Serotonin; Severe feather pecking