Dr. Joanna Hockenhull
Group housing provides an alternative to individual stables or box stalls, enabling horses to socially interact as well as move around with more freedom than a stable typically allows. However, a number of concerns have been raised concerning the feasibility of group housing in practice. Many of these, for example the mixing of unfamiliar horses and the ease of removing an individual horse from a group system, were addressed in the collaborative project on group housing horses under Nordic conditions undertaken by researchers in Denmark, Sweden, Norway and Finland around 5 years ago. The researchers found that these concerns were typically unfounded and made recommendations on how group housing can be best implemented to enhance horse welfare and human safety. Yet despite these positive findings, group housing systems are still a rarity in many places.
But it seems like the Nordic countries are not giving up that easily! This study, again from Sweden, set out to investigate the evidence behind another anecdotal concern regarding group housing. Apparently, sports horse trainers believe that group housing systems don’t enable sports horses to get the rest they need to aid recovery and enhance their performance; in short that keeping a sports horse in a group housing system will impair its ability to perform. This belief is obviously a large barrier to overcome if group housing is to become more widely adopted by the equine industry. Anecdotally many leisure horse owners, while not under the same pressures as competition riders, take their lead from these professionals when it comes to the management of their horses. Consequently, breaking down the barriers to group housing voiced by professionals is likely to have a beneficial impact on the wider equine population.
This study looked at the recovery of energy balance after competition-like exercise in eight standardbred trotters. The horses were split into two groups of 4, each experiencing two conditions for 21 days but in different orders with a short 3-day break in between to transition to the different housing system. The conditions were free-range group housing and an individual box stall. Within the box stall condition, the horses had 4-5 hours turn-out per day in a sand paddock with other horses, so they were not totally socially isolated for this part of the experiment. The horses underwent two exercise tests (being driven in a harness race sulky) on days 7 and 14 in each condition. The horses received ad lib forage throughout the study and forage intake was measured during the last week in each housing condition. Other measures taken included the body condition, weight and temperature of the horses. In addition, blood samples were taken at various points on the days of the exercise tests and the horse’s heart rates were recorded during the races themselves and into the recovery period.
The researchers found that the short-term (3-7 hours) metabolic recovery differed very little between the two housing systems indicating that the anecdotal concerns about group housing hindering recovery are unfounded. In fact, the findings suggest that in the longer-term group housing may actually promote recovery through increasing appetite and so forage intake in comparison to individual stabling. Reduced post-exercise appetite has been previously reported in individually stabled performance horses. Based on the findings of this study, group housing horses may be one way to overcome this problem. Eating is typically a synchronised behaviour within a group of horses, and it is likely that this group synchronisation aids recovery by stimulating motivation to eat.
We increasingly hear about the importance of having a scientific evidence base to support the decisions we make. It is studies like the one reported here that are so important to establishing this evidence base. No one study can do it alone, it is the fitting together of lots of different studies exploring the same issues from slightly different angles that come together to form a strong foundation on which to base welfare recommendations. This study, while small, adds another important layer to those foundations, and weakens the barriers to the use of social housing for our horses – JH
Connysson M, Rhodin M, Jansson A (2019) Effects of Horse Housing System on Energy Balance During Post-Exercise Recovery Animals 9 976; doi:10.3390/ani9110976