Forage is the most important part of your horse’s diet. Forage comes in many different varieties, the most common being grass, hay or haylage. It provides your horse with the necessary fibre to keep the digestive system functioning properly. Horses are known as trickle feeders, and in the wild will spend approximately 16 hours a day grazing. The horse’s stomach is different from ours, in which it constantly produces gastric juices. If the horse’s stomach is empty for longer periods of time, these juices will start to wear down the lining of the stomach, instead of breaking down fibre as it is designed to. When gastric juices are allowed to come in contact with the lining of the stomach, they cause painful ulcers. Other consequences of not feeding your horse often enough can be colic.
The vitamin and mineral contents in forage is normally not adequate to cover your horse’s needs. Your horse needs to have its vitamin and mineral requirements covered in order to ensure optimal health and functioning of all its physiological systems.
Types of forage
Grass – the most common source of forage and fibre for horses who live out, or go out in the field for longer periods of the day. Dry matter content in grass is normally around 10-20%. This means that for every 10 kgs of grass, we only get 1-2 kgs actual food. For an average 500 kg horse in light work, this means the horse would need to eat 50 kgs of grass daily. Out of these 50 kgs of grass, only 7.5kg would be food, while the remaining 42.5kgs would be water.
Hay – the most common source of forage and fibre fed to horses who do not live out, or do not have sufficient grass quality or access. Hay is normally between 80 and 88% dry matter, which means an average 500kg horse in light work would need 9 kgs daily. Hay is a processed form of grass, normally dried to the desired dry matter content.
Haylage – a common source of forage and fibre fed to horses who do not live out, or do not have sufficient grass quality or access. Compared to hay, haylage is normally between 48% and 70% dry matter, which means an average 500kg horse would need 13kgs daily. Haylage is ideal in situations where you may want to feed more forage, but ensure your horse does not get too many calories.
- A horse’s diet is based on dry matter intake, not calories. If your horse is not satisfied when fed 7.5 kgs hay, you could substitute some or most of it with haylage, and feed larger quantities without increasing the calorie contents.
- Forage should be the main part of your horse’s diet, and aim to cover as much of the nutritional requirements as possible. Once the horse’s minimum dry matter intake has been covered, you can add in for example a balancer to ensure your horse’s vitamin and mineral requirements are covered.
- In an ideal world, your horse would have access to ad lib forage to satisfy both the behavioural and physiological need to trickle feed. Many horses can get “grumpy” if they do not have sufficient access to forage.
- It's important to remember that the vitamin and mineral contents of fluctuate with seasons.
- Many conditions are associated with insufficient forage quality or amount, including ulcers, colic and nutritional laminitis.
- When calculating your horse’s ration, make sure to know what type of forage your horse gets. The minimum dry matter intake for a 500 kg horse at maintenance levels is 7.5 kg DM. If your horse lives out, this means 50 kg of grass daily. If your horse is fed on hay, it means 9 kgs daily.