ugust brings many changes to a horse’s feeding program. Even if the grazing season is still ongoing, it is wise to already review the upcoming indoor feeding period.
Hay is the horse’s most important source of nutrition. Its appearance does not tell the whole story—hay that looks good may still be nutritionally inadequate. A hay analysis reveals what the hay actually contains. With the help of an analysis, feeding can be planned more accurately and supplemented as needed.
The most important hay values and what they mean
How do the values affect feeding and how should they be interpreted?
1. Dry matter
Determines how much hay the horse needs on a dry-matter basis (kg/day).
Dry hay has a greater volume than silage because it contains less water.
2. D-value
High D-value → energy-rich hay, suitable for working and growing horses.
Low D-value → low-energy hay, suitable for overweight horses, but values that are too low (<55%) may lead to nutrient deficiencies.
3. Crude protein
Adequate protein supports muscle development and metabolism.
If levels are too low, the horse requires protein supplementation.
4. Sugar
High sugar content may pose a risk for horses prone to laminitis or obesity.
If necessary, hay can be soaked to reduce sugar content.
5. Fiber (NDF)
Provides satiety and supports gut function.
High fiber suits overweight horses, but excessively coarse hay may be poorly digestible.
What is good hay like? – Target values
Working and sport horses:
• D-value: 68–72%
• Crude protein: 75–90 g/kg DM
• Sugars: <120 g/kg DM
• Fiber (NDF): 500–600 g/kg DM
Light work / maintenance horses:
• D-value: 60–68%
• Crude protein: 60–75 g/kg DM
• Sugars: <100–110 g/kg DM
• Fiber: 550–650 g/kg DM
Laminitis-prone / easy keepers:
• D-value: 58–65%
• Crude protein: 60–70 g/kg DM
• Sugars: <100 g/kg DM (preferably <80 g/kg DM)
• Fiber: >600 g/kg DM
Hay for easy-keeping horses
- A lower D-value provides less energy, allowing the horse to eat more without gaining weight.
- Keeps the horse satiated and supports gut function.
- However, excessively low D-values (<55%) are not recommended due to poor digestibility and insufficient nutrients.
- Add supplements only as needed (protein, minerals, vitamins).
Always make dietary changes slowly to allow the horse’s digestive system time to adapt.
Sources (Finland):
- Luke – Feed tables and feeding recommendations for horses
- Hevostietokeskus ry – Horse feeding guide
- Suomen Hippos ry – Horse feeding and welfare publications
- University of Helsinki, Faculty of Veterinary Medicine – Equine nutrition
International sources:
- NRC (National Research Council) – Nutrient Requirements of Horses, 6th Revised Edition
- The Horse Magazine - expert articles on equine digestion and the nutritional values of feeds
- Kentucky Equine Research
(KER) - research and practical information on hay analysis and horse feeding
- British Horse Society
(BHS) - principles of horse feeding and hay evaluation
- Feed Advisory Board (UK) - guidelines for interpreting hay and silage analyses
