Hay or Haylage? The Feed Debate, by Lucy Harris

Hay and Haylage; what is the difference?  Hay is completely dried. Haylage is semi-dried. One is baled, the other is wrapped. But are these the only differences between hay and haylage? How do these differences affect the nutritional value? Can they have differing influence on horses’ performance, health and wellbeing? Time to find out.

The most obvious difference between hay and haylage, is the way in which it is made. Hay is usually cut between the months of May to August, weather permitting. It is cut, left to dry on the ground and then turned in order to ensure it is sufficiently dried. Hay is often ‘turned’ more than once to ensure that the moisture levels are reduced to a level around fifteen to ten percent. Ensuring that hay is sufficiently dried is its preservation method. Reducing the moisture level to such a low point ensures that the risk of mould development during storage is kept to a minimum. ‘Meadow Grass’ is the common and preferred type of grass utilised in hay production, resulting in hay often being referred to as ‘meadow hay’.

Haylage is cut like hay, but only allowed to semi-wilt and not dry completely. It is usually cut after grasses for silage, but several weeks earlier than grass cut for hay. Haylage is often baled between twenty four and forty eight hours of being cut or when the levels of moisture are only reduced to around forty five to fifty five percent. The bales are then compressed and wrapped in multiple layers of plastic, often known as ‘double wrapping’. This eliminates oxygen reaching it and creates the anaerobic conditions needed for desirable fermentation of the haylage to occur. This ‘desirable fermentation’ is necessary to allow bacterial species such as lactobacilli which are naturally present in the crop to utilise water soluble carbohydrates to survive and produce lactic acid. The production of lactic acid is so important as this is what causes the pH to drop to a level between 4.8 and 5.8. This drop in pH inhibits the growth of undesirable organisms; these are what we more commonly think of as mould.

So, we know the differences between how these two products are made; hay is preserved through its drying process and haylage by its wrapping process. But how does this really affect the nutritional value of either product?

The main difference is the way in which the leaf structure is preserved. In the case of hay making, the drying process leads to leaf fracture, a problem which can create dust and loss of the nutrients present in the grass. These include water soluble carbohydrates, protein, vitamins and minerals. In short, this means that hay has a significantly lower feed value than haylage.

Haylage typically has a higher feed value than hay due to the decreased level of drying involved in haylage production. Assuming the product is made correctly, haylage will typically provide higher levels of digestible fibre, energy and protein because these components are better preserved through minimised leaf fragmentation. Haylage made specifically for the equine market is often produced from specially grown grasses, which have a higher feed value than meadow grass. There are two very important differences between the nutritional value of the haylage produced from either of these grasses. Haylage produced from ‘Timothy’ Grass is grown specifically as a premium, high energy and high nutrient feed stuff, suited to thoroughbreds or horses in hard, competition work. ‘High Fibre Rye Grass’ is also grown by haylage producers for the equine marketplace. It has a lower energy value than ‘Timothy Grass’, and is therefore suited to ‘good doers’ or ponies prone to laminitis whilst still having the sweet smell associated with haylage, which often tempts fussy eaters.

The next question to ask is: ‘what is the most suitable for my horse?’ To this, there are a number of important factors to consider. Obviously, every equines nutritional needs are different, and there are no hard and fast ‘rules’ as to what works best for each individual. However, the pro’s and con’s of each feed should be considered when choosing what is best for you.

Hay: The Pros 

• Hay, if of a good quality, will provide horses and ponies in light work, or who are ‘good doers’ with the sufficient amount of forage needed for energy.  In this respect it is also good for feeding ‘ad-lib’. With its lower energy value, enough can be fed to provide the horse with sufficient forage, without concern about unwanted weight gain associated with feeding haylage.
• Hay of good quality will also remain in good condition for a long period of time if stored correctly in a dry environment.
• Hay is significantly cheaper to buy than haylage.

The Cons

• All hay contains some dust and mould spores, and in a greater quantity than haylage because it is wrapped. This combined with its lower moisture content means these can become airborne and are a health risk to horses who are stabled frequently or have existing respiratory problems.
• To combat this, ‘soaking’ hay is an option. However this is time consuming, and leads to a further reduction of quality.
• Concentrated feed is often needed to be fed to supplement hay to ensure that protein and vitamin and mineral requirements are provided sufficiently.

Haylage: The Pros 

• Due to the manufacturing process, grass used for haylage tends to be younger and so is more digestible to horses meaning they tend to ‘do better’ on it because it provides higher levels of digestible fibre, energy and protein.
• Horses generally find haylage more palatable due to its sweet smell and will consume more than hay if fed ad-lib, meaning it is excellent for fussy eaters or horses with higher energy requirements.
• Whilst haylage is more expensive to buy than hay it can be better value, as less concentrate food needs to be fed because of its higher energy level.
• Correctly made haylage contains very few if any, mould spores, and because of its higher moisture content any which are present do not become airborne and, therefore, do not cause problems.

The Cons: 

• Haylage will start to deteriorate quickly once opened and should be used within a few days, meaning it is not always practical or economical for owners with only one or two horses as they cannot consume whilst it is at its best.
• Haylage can provide horses prone to weight gain or laminitis with an excess of energy provided by their forage. People cutting down the amount fed to reduce unwanted weight gain risk their horses having insufficient forage, which can lead to an increased risk of stomach ulcers and other digestive problems.
• Ensuring sufficient forage is so important in equines because this is what provides the horse with energy for winter warmth and maintains a healthy digestive tract to prevent problems such as stomach ulcers.

So there we have it. The differences between hay and haylage are considerable and each have their own benefits. Both feedstuffs have their individual advantages and disadvantages and these factors must be taken into consideration alongside each equines individual needs and requirements.

Lucy Harris