Olfactory stimulus as environmental enrichment for shelter dogs: a pilot study


  • Milene Paula Figueira Universidade Federal de Viçosa, Programa de Pós-graduação em Biologia Animal
  • Fernanda Fatima Rodrigues Silva Universidade Federal de Viçosa, Programa de Pós-graduação em Biologia Animal
  • Alice Ribeiro Universidade Federal de Viçosa, Departamento de Biologia Animal
  • Ita Oliveira Silva Universidade Federal de Viçosa, Programa de Pós-graduação em Biologia Animal; Universidade Federal do Sul da Bahia, Instituto de Humanidades, Artes e Ciências
  • Vanner Boere Universidade Federal do Sul da Bahia, Instituto de Humanidades, Artes e Ciências ; Universidade Federal do Sul da Bahia, Programa de Pós-graduação em Ciências e Tecnologias Ambientais https://orcid.org/0000-0002-2239-5782




Canis lupus familiaris, Environmental enrichment, Olfactory stimulus, Scents, Shelter


Environmental enrichment techniques include olfactory stimuli for improving animal welfare. This study aimed to analyze the reactions of 41 shelter dogs exposed to odorous stimuli, such as the method used in another study on wild canids. The focal animal method analyzed the dogs’ reactions, with all behaviors recorded. Behavioral responses were classified as positive (P+), negative (N-), or other (Ot). Independent variables were all dogs and the size of the packs. The behavior between the basal (without stimulus), exposure, and after-stimulus withdrawal was analyzed. For all dogs, olfactory stimuli significantly increased P+ (P=0.001) and N- (P=0.004), contrasting with the decrement of Ot behaviors (P=0.001) from the basal to the exposure phase. After the withdrawal of the stimuli, P+, N-, and Ot behaviors returned to basal levels (P>0.05). There were no significant differences (P>0.05) in the conduct of small or large packs exposed to stimuli. Dogs are sensitive to olfactory stimuli, but arousal is generalized to P+ and N-. It is undesirable to an N- increase for improvement of animal welfare. Contrary to what was observed in a study with wild canids, the method failed in shelter dogs because N- was increased. The introduction of sudden novelty (olfactory stimulus) in an impoverished shelter environment may have caused excitement in the dogs. It is suggested that changes in the method, such as stimuli exposition to each dog in an isolated room, are necessary to increase sheltered dog well-being.


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How to Cite

Figueira, M. P. ., Silva, F. F. R. ., Ribeiro, A. ., Silva, I. O. ., & Boere, V. (2023). Olfactory stimulus as environmental enrichment for shelter dogs: a pilot study. Brazilian Journal of Veterinary Research and Animal Science, 60, e203068. https://doi.org/10.11606/issn.1678-4456.bjvras.2023.203068