Written by Sharon Smith MSc SEBC(Reg) IEng BHSAPC
Humans are often in the presence of horses with food. ‘Food aggression’ between horses, or horse and human can occur even if treats are firmly off the menu. This behaviour can be grouped into three broad
1. True aggression is an emotional reaction, out of fear or previous trauma, that horse associates with specific triggers perceived to be threatening. It is rare, but it happens with very little warning, usually with teeth in full contact with the individual. A specific food (smell or appearance) could trigger the emotion, or food may be incidental, if the horse is restricted or restrained and cannot run away.
True aggression requires professional help and careful handling to address the triggers. Avoid developing fear (of hunger) or trauma-based food aggression by ensuring the 3F’s: Friends, Forage and Freedom. Feed plentiful hay, of the right calorie density for your horse’s weight management needs. A horse with a comfortable stomach and gut is unlikely to develop true food aggression, obviously. Feeding something pleasurable, like treats, is highly unlikely to invoke fear or discomfort and develop into true aggression.
2. Learned ‘food aggression’ is most commonly observed with humans. It is usually accidentally trained, but can still become very frightening and dangerous . We allow the horse to barge in before the bucket hits the floor. We carry hay into the field for them during winter, or when pasture becomes too short in summer. We do carrot stretches, while holding carrots. Humans ‘give up’ food to horses all the time. Posturing develops into aggression with repetition so there is likely to be a warning sign, which distinguishes it from true aggression.
The key to a good behaviour around food is to be aware of what the horse was doing the second before they ate. The horse doesn’t intrinsically know ‘right’ from ‘wrong’; just what works, and what doesn’t . The horse can be taught food is only available when he stands back or turns his head away. Alternatively, the horse can be removed from the stable and food put in before his return. Then, he discovers it for himself. The same approach can be used for bucket-feeding horse kept at pasture. The bucket is put on the floor, outside the field, and the horse led to the bucket. The routine change can take a little thinking about, at first, but soon becomes a habit. Note: it is natural for horses to turn the ears backwards while lowering their head into a bucket. This motion is different from pinning them flat down.
3. Extreme frustration or arousal behaviour, such as: head-tossing; targeted pawing and kicking out with hind-legs towards the human. The behaviours are as might happen with another horse protecting limited food . In these cases, which may be mistaken for ‘playful’ behaviour, the horse is being denied something they want, and expect. Lack of mental stimulation, denial of ethological needs , or using very tasty food as treats can cause an animal to place too much ‘value’ on all food, resulting in potentially dangerous behaviours when it is withheld .
Failing to reward a previously rewarded behaviour creates mild, temporary frustration, which should motivate an animal to try harder. It could motivate some fabulous behaviour, like a more expressive trot. Frustration could also motivate an unwanted behaviour, like tearing jacket pockets in an attempt to get another mint. Too much frustration is aversive, not positive. A frustrated horse may have been accidentally confused, or conflicted by being asked to do something they are not capable of, mentally or physically . After meeting ethological needs, it is possible to devalue food used for training by providing it at undemanding times. Less palatable food, eg. chaff, may also help.
If worried about hand-feeding treats, it is still possible to use food in training. For example, carrot stretches have been taught using a ‘target’ and clicker, rather than luring (M. Wake, personal communication, January 8, 2018). Also, treats can be dropped or thrown into a bucket as a reward. Wither-scratches suit the vast majority of horses, just as well as food, reducing heart rate and stress hormones , and easier than food to administer when riding!
One final thought. Trainers now agree the ‘default’ method for every other animal in captivity or domestication is to use rewards, most often food rewards. Ever seen a rhino learning to stand on a weigh-scale ? Or a goldfish limbo ? Reward-based training when riding horses is more complicated, because we sit on them! But, if balanced and using well-fitting tack, sticks or spurs are not required to motivate horses. Food, or wither scratches, can replace them [10, 11] and there is evidence that positive training (in the opinion of the horse) results in lasting positive attitudes towards people  reducing the risk of true food aggression.
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