title: Effects of feather pecking phenotype (severe feather peckers, victims and non-peckers) on serotonergic and dopaminergic activity in four brain areas of laying hens (Gallus gallus domesticus).
abstract: Severe feather pecking (SFP) in laying hens is a detrimental behavior causing loss of feathers, skin damage and cannibalism. Previously, we have associated changes in frontal brain serotonin (5-HT) turnover and dopamine (DA) turnover with alterations in feather pecking behavior in young pullets (28-60 days). Here, brain monoamine levels were measured in adult laying hens; focusing on four brain areas that are involved in emotional behavior or are part of the basal ganglia-thalamopallial circuit, which is involved in obsessive compulsive disorders. Three behavioral phenotypes were studied: Severe Feather Peckers (SFPs), Victims of SFP, and Non-Peckers (NPs). Hens (33 weeks old) were sacrificed after a 5-min manual restraint test. SFPs had higher 5-HIAA levels and a higher serotonin turnover (5-HIAA/5-HT) in the dorsal thalamus than NPs, with intermediate levels in victims. NPs had higher 5-HT levels in the medial striatum than victims, with levels of SFPs in between. 5-HT turnover levels did not differ between phenotypes in medial striatum, arcopallium and hippocampus. DA turnover levels were not affected by feather pecking phenotype. These findings indicate that serotonergic neurotransmission in the dorsal thalamus and striatum of adult laying hens depends on differences in behavioral feather pecking phenotype, with, compared to non-pecking hens, changes in both SFP and their victims. Further identification of different SFP phenotypes is needed to elucidate the role of brain monoamines in SFP.
authors.affiliation: Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences (UIPS), Utrecht University, Faculty of Science, P.O. Box 80082, 3508 TB Utrecht, The Netherlands. Electronic address: m.s.kops@uu.nl.
authors.forename: Marjolein S
authors.initials: MS
authors.lastname: Kops
authors.forename: Elske N
authors.initials: EN
authors.lastname: de Haas
authors.forename: T Bas
authors.initials: TB
authors.lastname: Rodenburg
authors.forename: Esther D
authors.initials: ED
authors.lastname: Ellen
authors.forename: Gerdien A H
authors.initials: GA
authors.lastname: Korte-Bouws
authors.forename: Berend
authors.initials: B
authors.lastname: Olivier
authors.forename: O
authors.initials: O
authors.lastname: Güntürkün
authors.forename: J Elizabeth
authors.initials: JE
authors.lastname: Bolhuis
authors.forename: S Mechiel
authors.initials: SM
authors.lastname: Korte
mesh_terms: D000374:Aggression / Q000502:physiology*; D000818:Animals; D001522:Behavior, Animal; D015306:Biogenic Monoamines / Q000378:metabolism / Q000502:physiology; D001921:Brain / Q000502:physiology*; D001923:Brain Chemistry / Q000502:physiology; D002645:Chickens / Q000502:physiology*; D002851:Chromatography, High Pressure Liquid; D004298:Dopamine / Q000378:metabolism; D005241:Feathers; D005260:Female; D006897:Hydroxyindoleacetic Acid / Q000378:metabolism; D010641:Phenotype; D012149:Restraint, Physical; D012701:Serotonin / Q000378:metabolism
chemical_list: D015306:Biogenic Monoamines; D012701:Serotonin; D006897:Hydroxyindoleacetic Acid; D004298:Dopamine
keywords: Feather pecking behavior; Laying hens; Monoamines; OCD; Thalamopallial circuit