Every day, we get emails from horse owners, many of them desperate because they don't know what is wrong with their horse.  "My mare grinds her teeth". "Just seeing the girth makes my gelding hits his stomach with his hooves." "My horse is a poor eater and gets colic often."

But what is the cause?

There is usually a good reason for sudden weight loss. But what are the symptoms of dental problems or worms, what rules must I follow, what triggers stress in my horse and how will I recognise diseases? The wealth of different opinions – from stable colleagues, riding instructors, feed consultants and in the many online forums and groups – is so large and varied that one can quickly lose perspective.

Equine dental problems

A horse may have dental problems if, for example, it chews and lets the feed fall from its mouth, or suddenly eats hesitantly. Frequently, it may also be mouthy on the bit, and perhaps resists accepting the bit at all. Other symptoms include:

• Slow eating
• Unusual chewing movements
• Dropping bits of concentrated feed
• Quidding
• Excess salivation
• Lack of interest in feed
• Hay balls
• Difficulty chewing
• Pushing feed around in the mouth
• Sucking feed: cheeks thick from pulling roughage between the cheeks sharp
• tooth edges

Chewing causes pain to the horse, severely impairing its well-being. It eats less, and what it does eat is insufficiently chewed and cannot be digested properly. There is also insufficient salivation of the feed. Saliva contains the substance bicarbonate, which acts as an acid buffer to protect the stomach lining from gastric acid attacks and thus from stomach problems (gastritis, gastric ulcers).

Deworming your horse

Parasites in the stomach and intestines play an important role in sudden weight loss in horses, as they impede food intake in the intestines. If it also develops a shaggy coat and a raised "drum-belly", one should consider deworming.

Proper conditions for keeping horses

A lot has been written about conditions for keeping horses, and every horse owner tries to provide his horse with the best conditions possible. It is important to keep an eye on the needs of horses, especially with regard to high-ranking and low-ranking animals. For example, peace in the group is usually maintained as long as low-ranking animals find enough space to stay out of the way of the others. This will also keep the level of stress in the stable low. Where space is limited, however, low-ranking animals do not find the peace and quiet to digest the feed they eat, and they may not digest their feed sufficiently and lose weight from stress.

Stress and nervousness in horses

Peace and comfort – ‘Wouldn’t that be nice’, owners of nervous horses may find themselves thinking. A nervous horse finds no peace, even at feeding time. It's a vicious circle: too little food intake, too little energy, too little willingness to perform, too much stress during training, too much gastric acid, which in turn cannot be buffered sufficiently because too little is eaten.

Pain or disease in the horse

If your horse suddenly looks emaciated, he may be ill. First consider gastric ulcers or gastritis, which may be caused by stress, too much concentrated feed and too little roughage, or too-long periods between feedings. If colic symptoms occur repeatedly and the horse does not gain weight despite adequate feeding, it is advisable to order a gastroscopy for some clarity.

If you are worried about your horse and want to know what is causing his weight loss, these 10 questions will help you prepare for the vet’s visit:

1. When did the horse start losing weight (maybe it was always so thin)?

2. What changes were associated with the weight loss (more stress, different feed, different stall, different training, herd hierarchy issues)?

3. Has the horse been sick?

4. When was the last time it was dewormed?

5. When was the last time its teeth were checked?

6. Has the horse "only" lost weight or are there other physical signs (dullness, loss of appetite, limited performance, muscle loss, lack of shine, fragile hooves)?

7. What is the quality of the feed?

8. Are there any poisonous plants growing in the pasture where the horse is turned out?

9. Does the horse eat the feed it is offered, or does it leave some in the trough?

10. Does the horse have access to roughage and does he get enough of it?

In many cases a veterinarian will ultimately determine that a gastric ulcer lies behind the complaints. The problem seems to be that its symptoms are not interpreted correctly by many riders.