by Dr Jo Hockenhull
So often when we are talking about equine welfare in the western world, we overlook our stallions. All too frequently stallions are managed even more restrictively than mares and geldings; often stabled 24/7, living alone and subjected to aversive handling practices as a result of their ‘aggressive’ and ‘dangerous’ reputation. But there is growing evidence that this doesn’t need to be the case and that stallions can be managed in ways that better meet their welfare needs.
This review paper by Gehlen and colleagues from Germany brings together literature describing research on stallions management to see whether stallions can be housed in a more welfare friendly and species-appropriate way. Since 1990, 50 relevant papers in German or English had been published detailing research on stallion husbandry, group husbandry, and/or husbandry-related diseases and all were included in the review.
The authors’ findings present a stark reality of how many stallions live their lives and the consequences of this with multiple reports of socially isolated stallions showing undesirable behaviour such as aggression, stereotypies and self-mutilation, as well as difficult behaviour when handled. While some establishments did manage their stallions in groups these were often the minority and limited to pony stallions, while horse stallions were managed singly. The success of managing stallions in groups was also attributed to how they had been reared and there is some suggestion that breeding may also be an influencing factor. So, while group-housing be a positive influence on stallion behaviour there appear to be caveats to its use.
The authors report a study run at the Swiss National Stud, where stallions were introduced to each via ‘socialboxes’, individual stables that provided limited opportunity to engage in tactile contact with the neighbouring horse. Following this two-week socialisation period, the stallions were turned out together in a pasture that was well equipped with multiple escape routes and feeding resources to reduce competition and allow horses to avoid aggressive interactions. Aggression reduced over the first four days on pasture, and only minor injuries were reported. The stallions engaged on mutual grooming, play and ritualised interactions (posturing rather than aggression, so not associated with injury). The stallions were easier to handle, more relaxed and overall had greater physical and mental wellbeing, demonstrating that group-housing stallions can be achieved successfully and has tangible benefits for both horses and humans.
But we know some stallions cannot be housed with others, due to their rearing, previous experiences or inappropriate social behaviour often stemming from spending too long in isolation from other horses. What can we do to promote better welfare in these stallions? Similarly, group-housing stallions may not be appropriate for establishments that experiences frequent changes in their equine population which will disrupt the formation and maintenance of bonds between individuals. The authors discuss what solutions can be suggested by previous studies with photos of these in action, for example turnout with a gelding or using a version of the socialbox that allows stallions the opportunity for some degree of physical interaction with each other, or a gelding, but reduces the risk of injury and allows them to remove themselves from the social contact should they wish. While an increase in stallion posturing behaviour may be seen in this type of housing, this is usually only for the first two hours. If this type of contact is not appropriate, allowing visual, auditory and olfactory contact with others may be a possibility rather than confining stallions away from all input from other horses. One example of this was stallions stabled individually in a barn system that had adapted stable doors to allow them to reach down to feed provided on the central corridor floor, meaning that they could feed together. The authors comment that it is very rare that a stallion is better off alone, and perhaps castration should be considered for welfare reasons, particularly in stallions not used for breeding who cannot be managed in a species appropriate manner.
There are numerous factors that must be taken into consideration when attempting to change management to improve stallion welfare, as there are for any horses, for example having sufficient space and enough resources that conflict can be avoided. The authors review these in the discussion and acknowledge that for some individual stallions and individual establishments group-housing may just not be appropriate. But they make the important point that that does not mean that management should simply continue as it has always done. Efforts should be made to optimise any stallion management to ensure that their species-specific needs are met as best they can be in that context.
It is great to see the often-neglected topic of stallion welfare being addressed in this review. The various social management strategies discussed by the authors are relevant to all horses, not just stallions, and act as a reminder that we should never just accept that we have done all we can to optimise the management of our horses to meet their species-specific needs. A bit of thought and creativity can make all the differences to our horses welfare.
This paper is published in the open access journal Animals and so freely available for all to read:
Gehlen, H.; Krumbach, K.; Thöne-Reineke, C. Keeping Stallions in Groups—Species-Appropriate or Relevant to Animal Welfare? Animals 2021, 11, 1317. https://doi.org/10.3390/ani11051317