Home Health and vet Olfactory stimulation as environmental enrichment

Olfactory stimulation as environmental enrichment


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Graphics/Photography: A.C.B. de Lima; M.S.P. Hernandes

Equine welfare is a topic that has attracted the attention of both the scientific community and the public. In the domestic environment, horses are often kept in suboptimal conditions that limit the expression of species-typical behavioirs and compromise their welfare.

Environmental enrichment strategies have been identified as an interesting option to make the domestic environment more interactive and complex, resulting in an improvement in the animal’s quality of life. Olfactory stimulation, a form of sensory environmental enrichment that aims to trigger the sense of smell through the introduction of odors, has shown promise for horses. This review aims to present current information on equine olfaction, demonstrating its relevance as a sensory modality and exploring the potential that olfactory stimulation has as environmental enrichment for the species.
Horses constantly face several challenges inherent to the domestic environment, and it is common for the expression of their natural behavior to be drastically limited. Environmental enrichment has been suggested as an alternative to improve the captive situation of domestic horses. Among the recently proposed enrichment strategies, olfactory stimulation has emerged as a method for improving several aspects related to animal behavior. Olfaction is a sensory modality that plays a significant role in the expression of equine behavior, and in recent years, studies have shown that olfactory stimulation can influence the physiological and behavioral parameters of horses.
This review provides current information on the anatomical particularities of the equine olfactory system, presents the physiological mechanisms involved in the odor detection process, and demonstrates how stress can interfere with this process. Finally, the use of olfactory stimulation as an environmental enrichment for domestic horses (Equus ferus caballus) is explored. The need for new studies that answer pertinent questions related to this topic is discussed throughout the manuscript.

1. Introduction

Domestic horses face several challenges inherent to the environment in which they are kept and managed. To deal with these challenges, animals rely on behavioral and physiological stress responses that, although adaptive, when provoked for a long time and/or frequently, can compromise their welfare [1,2].
Environmental enrichment has been suggested as an alternative to improve the captive situation of domestic horses and the safety of handlers [3,4]. In general, enrichment strategies involve providing sensory stimuli, new objects, social contacts, and the possibility of voluntary exercise [4], which results in an interactive and complex environment, allowing animals to express species-typical behavioral patterns. Olfactory stimulation is a form of sensory enrichment that holds considerable potential. Odors are relatively cheap, easy to store, and can become dynamic in time and space, rendering an aspect of novelty [5], which makes olfactory stimulation interesting from a practical point of view... To read the complete article you need to be a subscriber