e q u i n e
Group Housing Solutions Kathie Gregory suggests alternative housing options for horses to ensure they have access to social interaction with conspecifics
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s discussed in my previous article (see Stable Life, BARKS from the Guild, May 2019, pp.46‐48), there are numerous, well documented issues arising from housing that keeps horses in isolation. What, then, are the alternatives and what impact do they have on the horse? Reactivity, manageability (Rivera, Benjamin, Nielson & Zanella, 2002), activities horses engage in—often called the time budget—(Benhajali et al. 2007) and learning are all influenced by the type of housing horses are kept in, and all have an impact on equine welfare and the safety of both people and horses. Routine in healthy free ranging horses is predictable, with repetition of activity patterns from day to day (Berger, Scheibe, Michaelis & Streich, 2003). Horses have evolved as a social species to live in groups. The group is essential to the survival of the species, providing safety in numbers, working together to detect and assess any potential threat. The fact that many horses are now kept in a domesticated environment where there are no predators has not changed their survival mechanism. As such, significant issues arise from a lack of social contact, not being part of a group, and the lack of opportunity to form friendships. It is intrinsic to the psychological and physiological welfare of a social species that they are able to live in a social environment. When horses are isolated, have minimal contact with others, and lack the freedom to form groups, they suffer higher levels of stress than those with access to social interactions. One of the reasons for this is the survival mechanism (stress response) that continues to operate in the domestic setting. Without the support of the group, however, each horse is on his own and this can lead to increased vigilance and continued activation of the stress response, which should only activate during emergencies. This may be a contributing factor in chronic stress related disease (Sapolsky, Romero & Munck, 2000). A study by Yarnell, Hall, Royle & Walker (2015) of horses kept for a period of time in four different housing options found a variety of indicators confirming that horses who do not have adequate social interaction are predisposed to suffer from a number of issues. The four housing options were broken down as follows: • Single Housed No Contact: As the name suggests, horses are kept in complete isolation, each in their individual stall. There is no possibility of any physical contact due to solid walls between neighboring stalls. • Single Housing Semi Contact: This type of housing keeps the horse in isolation, but he is able to see and make some minimal physical contact with horses on either side of him. • Paired Housing: Two horses are housed together and have full contact with each other. As with isolation and single semi contact housing, if there are several pairs of horses housed in one barn, they would also likely be able to see those horses on the opposite side of the barn.
Horses have evolved as a social species to live in groups. The group is essential to the survival of the species, providing safety in numbers, working together to detect and assess any potential threat.
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BARKS from the Guild/July 2019
© Can Stock Photo/joyfull
In a natural environment, horses live in groups where they have the opportunity to enjoy social contact, be part of a group, and form friendships.
• Group Housing: This is the most natural housing solution. All horses in the group have full physical contact with each other. It most closely mimics the natural social grouping of horses. The study measured adrenal activity via non-invasive fecal corticosterone metabolite analysis (fGC), eye temperature (as a measure of recording the stress response), a behavioral analysis of the horses’ activities, how long they engaged in them, and, finally, how easily the horses could be handled. Horses in group housing with full contact recorded the lowest levels of adrenal activity on the fGC test with levels increasing in tandem with increasing levels of isolation, and single housed no contact giving significantly higher levels than the other housings. Group housing with full contact also recorded the lowest eye temperature readings. Horses that were in housing that had no, or limited, social time were much more difficult to handle, a finding supported by Rivera et al. (2002). Keeping horses in group housing reduces stress (Mayes & Duncan, 1986). The result of stress-free horses is that they show similar daily patterns to freeranging groups, and are active in seeking the company of the other horses in the group. This is in direct comparison to horses kept in stalls, who spend more time displaying stereotypical behaviors (Heleski, Shelle, Nielson & Zanella, 2002).
Stereotypic Behavior The link between stereotypic behavior, housing conditions and social isolation has been experimentally demonstrated by Visser, Ellis and Van Reenen (2008). Oral stereotypical behaviors have been noted as common in captive ungulates (Bergeron, Badnell-Waters, Lambton & Mason, 2006; Mason & Rushen, 2006). Crib biting can take up as much as 65%