The Importance Of Fibre in a Horse’s Diet and How to Choose the Right Type of Hay
By Purina Canada
In order to comprehend the role of hay and pasture, you must first understand what fibre is. Fibre is simply the tissue that composes the main structure of plants (including the plants found in hay and pasture). Comparable to the structure of a house, fibre allows plants to stand up relatively straight while preventing infection by creating a protective barrier against illness and insects. Fibre consists of four main elements, each one possessing different levels of fermentability:
- Pectin: very fermentable
- Cellulose and hemicellulose: partially fermentable
- Lignin: non-fermentable
Fermentability is of importance because the large intestine is essentially a big fermentation chamber. It is here that the fibre contained in hay is digested through fermentation. This differs from the starch in grains, which is digested by the enzymes in the small intestine. Within the large intestine, the animal is only able to use fermentable fibre, namely pectin, cellulose, and hemicellulose. Non-fermentable fibre will be transformed into waste. With the help of essential bacterial flora, the large intestine transforms energy from fibre into volatile fatty acids. These volatile fatty acids can either be used as immediate sources of energy or transported to the liver where they can be converted to glycogen or fat reserves.
The digestibility of fibre contained in hay depends on the pasture’s plant species and maturity. In the springtime, you may have already noticed that as grass is just beginning to grow, it is very flexible. This is because during the early stages of growth, grass contains more pectin, cellulose, and hemicellulose than it does lignin. But as the summer progresses, higher proportions of lignin cause the plant to become increasingly solid and stiff, and thus less digestible for the horse. Two different hays can vary greatly in their composition. For this reason, all changes to a horse’s diet must be made gradually. While this concept is widely accepted when it comes to changing a horse’s feed, we often forget its importance when transitioning the horse to a new hay or forage. Gradual transitions are most critical when putting a horse to pasture. Grasses available to grazing horses are much different from the dry hay served inside. Outdoor pasture is much more fermentable than dry hay since it contains less lignin and its nutritional profile is very different. As with any other food, it needs to be introduced gradually to avoid disrupting the bacterial flora in the large intestine; lignin cannot be digested by the same bacteria as the other types of fibre. Given that any imbalance in the large intestine can lead to colic and laminitis, it is important to take all necessary precautions.
Read the full article on The Importance Of Fibre in a Horse’s Diet and How to Choose the Right Type of Hay HERE.