Forage
Forage is the most important part of a horse's diet and is rich in the essential fibers, but its nutritional composition can vary significantly. The category of forage includes; pasture, hay, haylage, silage, and straw. Products such as alfalfa and hay pellets are also considered forage
What is the difference between hay, haylage, and silage?
All three types of forage are conserved grass or pasture. The difference lies in how it has been stored and its dry matter (DM) content. The proportion of DM in forage indicates how much of the feed is actually nutrient-containing material and how much is water..
Hay
To produce hay, the grass must be dried until it reaches a DM content of 84%. It is at this DM level that the hay is dry enough that it will not begin to mold from its own moisture. However, it becomes very sensitive to moisture in its surroundings, which places high demands on storage conditions. Hay must be stored dry, otherwise, it will begin to mold.
Silage
Silage is a wet forage with a low dry matter (DM) content, ranging from 20-45% DM. This means that the majority of the silage is water (between 80-55%). For the grass to be ensiled, it is packed tightly after harvest and then sealed in plastic to create an oxygen-free environment. In this oxygen-free environment, the grass is preserved with the help of lactic acid bacteria that naturally occur on the plant. The lactic acid bacteria use the sugars in the grass and convert them into lactic acid, which lowers the pH level of the bale. In this environment, which is achieved in a properly ensiled bale, unwanted bacteria and microorganisms cannot survive or grow, allowing the forage to be preserved and used as feed long after it has been harvested. This process is called silage fermentation, and the result is silage.
Haylage
Haylage is a middle ground between hay and silage, with a dry matter (DM) content between 45% and 84%. In wetter haylage (under 65% DM), a certain fermentation process occurs, but in drier bales, no fermentation takes place. Instead, the feed is preserved due to the oxygen-free environment created when it is wrapped in plastic.
Would you like to learn how to measure the dry matter (DM) content of forage?
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