
What Counts as Roughage – and Why It’s So Important
Roughage includes pasture grass as well as its dried forms: hay, haylage, and straw. The basis of the feed should always be high-quality hay or haylage. A pasture is considered valuable not just when it contains the commonly known ryegrass, but when it is diverse and includes herbs. Biodiversity is key: species like quaking grass, sheep’s fescue, sweet vernal grass, various fescues, meadow-grasses, crested dog’s-tail, meadow oat grass, and timothy all offer particularly high value for horses. Horses should consume as much pasture grass as possible throughout the year.

“The horse’s most sensitive internal organ is the gut,” explains Dr. Olivier Brandenberger from the Hanseklinik für Pferde. “Concentrate should always be fed after roughage, when the stomach has already been partially filled with alkaline hay. This way, the sugar in the concentrate, which promotes acid production has a less harmful effect. Feeding hay first, followed by concentrate about half an hour later, can already make a big difference. Roughage protects the stomach, supports the small intestine, and promotes a healthy gut microbiome. It also acts as a natural acid buffer. Moreover, roughage provides occupation, satisfies the horse’s need to chew, helps prevent behavioral issues, and reduces stress. Chewing time is extended, and saliva production is stimulated, both of which play a key role in digestive health.”
Hay – The Trusted Standard in Horse Feeding
Hay is cut shortly before, during, or just after the flowering stage of grasses. The later the cut, the higher the raw fiber content. The cutting height should be at least five to seven centimeters to reduce the risk of foreign materials ending up in the hay. Under normal conditions, the drying phase takes just under a week, during which the hay is turned several times. After drying, the residual moisture must be below 15 percent. To test this, twist the hay as if wringing it, if the stems snap, it's dry enough. One major advantage of hay is its high raw fiber content, which is ideal for horses when the quality is good. This content typically ranges from 23 to 30 percent and has a particularly positive effect on intestinal activity.
Smaller bales are generally preferable to oversized ones, as they reduce the risk of mold formation.

For allergic horses, soaking or steaming the hay is a labor-intensive but effective solution. These methods only allow small amounts to be fed at a time and do not allow leftovers to kept for a long period of time. However, they can help manage allergies. Ten minutes of soaking is sufficient; otherwise, valuable minerals may be leached out. The same applies to steaming, if done too intensively, it can have similar effects. When soaking, always use fresh water, and when steaming, carefully follow the manufacturer's instructions to prevent bacteria and mold from developing.
Hay cobs are made from compressed hay and can serve as a substitute or supplement to traditional hay. They are especially suitable for horses with respiratory issues, as they are virtually dust-free. The production process involves drying, chopping, and pressing the grass into cobs using a gentle warm-air technique that preserves nutrients. However, it is essential or hay cobs to be thoroughly soaked before feeding to prevent health risks.
Haylage – A Low-Dust Alternative with Special Requirements
When producing haylage, farmers are far less dependent on the weather than when producing hay. Although it's still best to harvest the grass during a stretch of consistently warm weather, the drying time is much shorter, since the final moisture content of haylage can remain between 40 and 50 percent. The cutting time for haylage usually occurs earlier than for hay. While this results in a lower raw fiber content, it also makes the dried grasses less bulky and more manageable for the next step in processing. After drying for about two to three days, the cut grass is tightly wrapped in special plastic film to seal out air completely. Before wrapping, the material is heavily compacted to remove any air pockets.

Allergic coughing in horses can be triggered by hay dust or pollen in pasture grass. For horses with chronic respiratory issues, haylage is usually a good alternative to hay. One additional benefit is that, due to its higher protein content compared to hay, haylage can help reduce the amount of concentrate feed needed.
Haylage is also often used due to limited storage space. Hay requires a large, dry barn for storage, while tightly wrapped haylage bales can be stored outdoors. However, they should not be exposed to direct sunlight, which can lead to fermentation. Ideally, they should be stored on the north side of a building or in shaded areas. It’s also important that no moisture accumulates around the bales, as standing water—like with hay—can promote mold growth.
Handling and Feeding Haylage Properly
It is extremely important to check for proper conditions with haylage. It should never feel unusually warm. The term botulism often arises in connection with haylage. While Clostridium botulinum is rarely found in hay, the risk increases significantly if haylage is produced improperly. However, there are no reliable statistics indicating how frequently botulism is actually involved when horses die from colic.
Proper transport of haylage bales is essential, as the plastic wrapping must not be torn beforehand. Although the bales can be stored outdoors, it's crucial to ensure they are not damaged by playing children or animals, which could allow air to enter and trigger spoilage or bacterial contamination.

Haylage that is in good condition smells pleasantly acidic, feels slightly moist, and appears light green to green in color. The grass stems should be clearly visible. Light yellow, bright green, or black-brown coloration may indicate spoilage. Spoiled haylage is often mushy or extremely brittle. It smells unpleasant, like vinegar or butyric acid.
“While we humans often speak of varied diets, horses should not be fed changing forages all the time,” emphasizes Dr. Oliver Brandenberger. “Gut bacteria thrive best when they receive the same feed at the same time and in the same amount. A sudden change in forage, such as switching from hay to haylage can cause a large part of the gut flora to die off, leading to gas colic and diarrhea. The dead bacteria leave gaps that can, in the worst case, be colonized by pathogens like salmonella or clostridia, resulting in potentially life-threatening intestinal infections. If a change in forage is planned, it should be carried out gradually over two to three weeks.”
Silage for Horses – Why It Doesn’t Belong in the Stable
Silage is classified based on its dry matter content: haylage contains 50 to 60 percent, grass silage contains 30 to 50 percent, and wet silage contains 20 to 30 percent dry matter. The latter must never be used for horses, and even grass silage is not recommended. In general, horses do not readily accept silage. Moreover, its nutritional composition is unsuitable for horses and can lead to digestive disturbances and other health problems.
Straw – Only Bedding, or Also a Feed Option?

Feeding quality can be maintained even in poor hay years by supplementing with straw. To a certain extent, straw should be included in the ration anyway, especially when horses are kept in shavings boxes or other bedding alternatives that are not edible. However, hay or haylage must never be omitted, as they are essential for healthy feeding practices.
Up to one-third of the horse’s roughage needs can be covered with straw. Common types used include wheat, rye, and oat straw. Horses tend to find rye straw less palatable than oat straw. Wheat straw is the most commonly used, as it absorbs moisture well and has a relatively neutral taste. Straw is quite prone to mold. If it feels damp, it should not be used as bedding, as it may already be contaminated. Black or grey patches also indicate mold. When shaken out, straw should release only a minimal amount of dust, this signals good quality.
In general, high-quality straw, when fed in moderation, has a positive effect on digestion due to its high fiber content.
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