…He becomes aggressive, pins his ears back and has been known to charge horses in the next-door field, skidding to a halt at the fence. Why is he like this?
Perry Wood answers:
There could be various explanations for this behaviour. The first thing I would do is to have him blood-tested to make sure he has been completely gelded. It may also be that he was gelded late and retained some of the aggressive stallion behaviours. Although this doesn’t help you resolve the problem, at least you’ll understand a little more of why it is happening.
Perhaps if he has a long period of stability with regards to his field companions, he may settle. In the wild, horses don’t just get moved around and constantly introduced to new equine individuals – many tend to spend their lives with the same regular herd. Therefore, trying to arrange things so that he doesn’t have to re-adjust should help.
You don’t say if the companions in the field are mares or geldings, but perhaps one or the other only would help him. Also, if there are mares over the fence and he lives with a gelding, or vice versa, he may be tempted to attack or defend in response to the mares being there – ie, he will attack geldings to guard ‘his’ mares.
Another possible reason for the behaviour is that he was kept alone for extended periods in his past. I have known a number of horses who lived alone or, for example, with cattle for a year or more, and their social skills and behaviour in the herd were permanently affected. They usually only became settled when they latched on to a particular individual, but then they became overly attached to that one horse, which consequently brought its own difficulties.
Whatever the source of the behaviour, you need to manage it in a way that is safe for the other horses. Electric fencing to separate them when they are first turned out together may be a way for them to get to know each other for a few days or weeks, until they are settled in one another’s company. Then it may be safe to turn them all out together.
You may also wish to explore any herbal supplements that claim to reduce aggression in horses. And you might find that with a lot of work – for example, long hacks every day – his energy is better directed, hopefully making him more relaxed in the pasture.