It is not unusual for a horse to suddenly lose their appetite, in most cases this will only last a few days but if it is an ongoing problem we have to work out why the horse is not eating so that we can find the solution to help improve appetite.
If you are worried in the first instance it is important to check with your vet, and if there have been no environmental or work related changes that you feel may have affected appetite you first need to check the quality of the feed. It is important to check the feed expiration date and to store feed correctly in a cool, dry environment to prevent feed degradation, mould growth, or contamination. Make sure that you regularly clean feed containers and buckets, as a build up of dust and feed residues could be making your horse reluctant to eat.
If possible, increase turnout and feed high quality fibre such as hay / haylage to help increase the fibre content of the diet. Some horses may respond well to a high fibre diet, but if you feel your horse is struggling to maintain condition then switch to a high oil, energy dense feed. Adding oils and fats to a diet is an ideal way to help provide the horse with a higher calorie meal without increasing the volume of feed, benefiting horses with a poor appetite.
It is also important to feed little and often to help mimic the horses natural feeding pattern, splitting the concentrate ration into as many small feeds as possible. Ideally feed between two to four feeds a day, with no more than 2kg of concentrates at any one time.
For some horses changing or enhancing the taste of the feed may improve appetite. Mix in carrots or apples to make the feed more succulent, or try stirring in some molasses or flavourings like spearmint, garlic to help improve appetite.