Format

Send to

Choose Destination
Behav Brain Res. 2019 Nov 5;373:112056. doi: 10.1016/j.bbr.2019.112056. Epub 2019 Jul 6.

Neurophysiological correlates of stereotypic behaviour in a model carnivore species.

Author information

1
Department of Pathobiology and Population Sciences, Royal Veterinary College, University of London, UK. Electronic address: mdiezleon@rvc.ac.uk.
2
Department of Animal Biosciences, University of Guelph, Canada.
3
Department of Psychiatry, University of Florida, USA.
4
Department of Biomedical Sciences, University of Guelph, Canada.
5
Department of Psychology, University of Guelph, Canada.

Abstract

Stereotypic behaviour (SB) is common in animals housed in farm, zoo or laboratory conditions, including captive Carnivora (e.g. wild ursids and felids). Neurobiological data on housing-induced SBs come from four species (macaques, two rodent species, and horses), and suggest basal ganglia (BG) dysfunction. We investigated whether similar patterns occur in Carnivora via a model, American mink, because their SB is distinctive in form and timing. We raised 32 males in non-enriched (NE) or enriched (E) cages for 2 years, and assessed two forms of SB: 1) Carnivora-typical locomotor-and-whole-body ('loco') SBs (e.g. pacing, weaving); 2) scrabbling with the forepaws. Neuronal activity was analysed via cytochrome oxidase (CO) staining of the dorsal striatum (caudate; putamen), globus pallidus (externus, GPe; internus, GPi), STN, and nucleus accumbens (NAc); and the GPe:GPi ratio (GPr) calculated to assess relative activation of direct and indirect pathways. NE mink stereotyped more, and had lower GPr CO-staining indicating relatively lower indirect pathway activation. However, no single BG area was affected by housing and nor did GPr values covary with SB. Independent of housing, elevated NAc CO-staining predicted more loco SB, while scrabbling, probably because it negatively correlated with loco SB, negatively covaried with NAc CO-staining in NE subjects. These results thus implicate the NAc in individual differences in mink SB. However, because they cannot explain why NE subjects showed more SB, they provide limited support for the BG dysfunction hypothesis for this species' housing-induced SB. More research is therefore needed to understand how barren housing causes SB in captive Carnivora.

KEYWORDS:

Basal ganglia; Dorsal striatum; Environmental enrichment; Mink; Stereotypic behaviour; Ventral striatum

PMID:
31288059
DOI:
10.1016/j.bbr.2019.112056

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center