The association of environmental and genetic factors with behavioural traits in two popular purebred dog breeds

Presenter Juliane Friedrich
Authors Juliane Friedrich (1), Per Arvelius (2), Erling Strandberg (3), Zita Polgar (1), Joanna J. Ilska (1), Sarah Lofgren (1), John Hickey (1), Marie J. Haskell (4), Pamela Wiener (1)
Affiliations 1. Division of Genetics and Genomics, The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Midlothian, EH25 9RG, UK; 2. Swedish Armed Forces Dog Training Center, Box 194, SE-195 24 MÄRSTA, Sweden; 3. Department of Animal Breeding and Genetics, Swedish University of Agricultural Sciences, PO Box 7023, S-750 07 Uppsala, Sweden; 4. Scotland’s Rural College, Edinburgh, EH9 3JG, UK
Presentation Type Talk

Abstract

As a companion animal, a dog’s lifestyle is mainly determined by its owner. A major component of a dog’s well-being relates to its integration into the physical and social environment provided by the owner. Discrepancies between the dog’s genetically-influenced temperament and the owner’s lifestyle might lead to the occurrence of unwanted behaviours that affect both the owner-dog relationship and the dog’s well-being. A better understanding of the relationship between genetic predisposition, environmental factors and the expression of behavioural traits may help to reduce behaviour problems in pet dogs in general and to address breed-specific needs.
We characterised owner-assessed behavioural traits in Labrador Retrievers (LRs) and German Shepherd dogs (GSDs), which are among the most popular dog breeds worldwide and are used as both pets and working dogs, to analyse the association of behavioural traits with environmental factors and genetic markers.
First, principal component analysis (PCA) was used to define distinct behavioural traits based on the established Canine Behavioral Assessment and Research Questionnaire (C-BARQ) in both dog breeds separately. The resulting behavioural traits were generally consistent with the behavioural traits typically found by analysing C-BARQ questions in other dog breeds, but in addition, breed-specific behavioural traits were identified, e.g. “Fetching” and “Barking tendency” in LRs and “Resource guarding” and “Aversion being stepped over” in GSDs.
General linear models were applied to analyse the interaction between these behavioural traits and demographic factors of the dog (e.g. sex, neuter status, age, diseases experienced), its living situation (number of children, adults and other animals living with the dog, living place) and its management (e.g. puppy socialisation, amount of exercise and stimulation, training, activities). The analysis showed that various demographic and management factors were associated with behavioural traits in LRs and GSDs. In particular, levels of exercise and the “role” of the dog (i.e. pet, show or working dog) were strongly associated with behaviour in LRs and age and the number of commands for which the dog was trained in GSDs.
Although a large number of environmental factors were associated with behavioural traits, they still only explained a small proportion of the variance observed in the traits and thus, the genetic influence on behaviour in the dogs was also investigated. For LRs, several behavioural traits exhibited moderate pedigree- and genomic-based heritabilities and showed suggestive association with specific genomic regions in a genome-wide association study (GWAS). Estimation of heritabilities and GWAS in GSDs are being carried out to allow across-breed comparison.