When a horse suddenly goes off its feed, the reason should be clarified as soon as possible, because refusing food means physical stress for the horse.
There may be very different reasons why a horse refuses to eat
One possible cause is a change in feed quality, which is often not immediately apparent at first glance. Here you have to take a closer look. Hay, for example, should be green and contain no toxic plants. It should have a pleasant fresh smell, be dust-free and mould-free, and have a sufficient – but not woody – structure. To be on the safe side, you can have the feed undergo laboratory analysis, for example by LUFA. If the feed’s quality isn’t the cause, you should then take a look at your horse.
Horses often go off their feed when they are under stress or in pain. This is especially problematic when horses refuse their roughage, because they won’t produce saliva through chewing and their stomachs remain empty. This results in excess acid in the stomach and a drop in the pH value. When the stomach gets little or no masticated food and saliva, gastric acid can attack the stomach lining unhindered, which can lead to irritation of the lining and, in the worst case, gastric ulcers.
If the horse is known to suffer from gastric ulcers or generally has a sensitive stomach, a refusal to eat can also be the result of digestive complaints. Acute phases especially can cause extreme pain, and horses will then leave their feed uneaten. This causes a conundrum for the horse owner, who wants to try to get the food into the horse somehow, yet is aware of the limitations in feed due to the gastric ulcer diagnosis. If you seek information or advice, the number of opinions and answers you’ll get often surpasses the number of people you ask. Everyone has different advice and different experiences to share.
Some horse owners go to pieces when their horse won’t eat its hay. There are rarely alternatives, as often little consideration is given to individual horses in livery yards – they either get hay or haylage. Usually no other type of hay will be produced or bought for one horse. As a horse owner you need to be proactive and try out how to get roughage back into your horse.
In the acute phase especially, horses often refuse hay as this causes pain in the stomach when the stalks being digested reach the irritated and sensitive stomach lining. If your horse will no longer eat very coarsely structured hay, it is advisable to try hay with somewhat less structure, as the stomach lining may be less sensitive to it.
Horses in acute phases are also more likely to eat hay cobs than hay, as these are easier to digest and gentler on the stomach. Avoid lucerne or feed straw completely at first, as these may lead to further lesions of the stomach lining due to their high structure.