Why is forage so important?
It is somewhat ironic that we don’t really know how much fibre the horse needs each day. We tend to refer to how much forage a horse should eat, as this impacts their behaviour and welfare as well as their nutrition. Some of the effects of too little forage and/or fibre in the diet include:
- Increased acidity in the stomach – the saliva produced by chewing forage helps to neutralise acidity in the stomach.
- Colic – just as for humans, fibre in the diet helps to promote regular bowel movements, which push gas and material through, and out of, the gut.
- Leaky Gut Syndrome – too little fibre has been shown to result in a reduced mucus layer lining the gastro-intestinal tract. This exposes the cells beneath, which compromises their integrity. The gaps between cells become wider and allow substances to pass through into the body that wouldn’t normally do so.
When traditional forages like hay or haylage are in short supply or if a horse or pony can no longer manage the longer lengths of these forages, it is vital that alternatives are used to maintain forage intake. Products that can be used as alternatives are termed forage replacers.
Forage Replacers – Why Use Them?
There are a range of reasons why a forage replacer might be needed or beneficial.
- Forage shortage – hot, dry summers reduce the forage yield in areas of the UK. If your supply is reduced then topping up every day with a forage replacer is a better approach compared to running out completely and having to make a more drastic change to your horse’s diet.
- Forage that’s too good or not good enough! – long hot summers can also result in very highwater soluble carbohydrate(WSC) levels in some forages which will be too much for those with EMS, PPID or that are prone to laminitis. Using a low WSC forage replacer can help you manage your horse’s WSC intake. Equally, if your forage isn’t that great for some reason, then topping up with a more nutritious forage replacer can help to avoid weight loss and poor performance.
- Variety in the diet: Offering a bucket or two of chopped fibre alongside the usual forage ration is a great way to keep your horse interested and encourage foraging behaviour. This is beneficial for all horses and ponies but may be particularly useful for those with limited appetites or fussy feeders where offering a variety of fibre sources may help to increase the overall intake
- Does your horse have respiratory issues? – Equine Asthma also referred to as RAO and COPD, means that some horses need a super-clean forage source. Soaking and steaming may not be practical or possible to do in some situations which is when straw free forage replacers are particularly useful
- Is your horse struggling to chew hay or haylage? – poor dentition isn’t just a problem for older horses; diastemas can affect younger horses and ponies too. If they simply cannot manage longer length forages then a short-chopped forage replacer may be suitable or it may even be necessary to use pelleted fibres soaked into a mash.
Indicators a horse is struggling to chew forage
There are some very obvious signs such as quidding where balled up pieces of food are dropped out of the horse’s mouth and tend to accumulate around the hay net or feeder. However, there are some earlier more subtle signs. Studies have shown that pieces of fibre greater than 3.6mm in the horse’s droppings are an indicator of dental abnormalities and for donkeys, the threshold length is slightly shorter at 3.3mm due to differences in anatomy.
Feeding Forage Replacers: What you need to know
- Not all high fibre feeds can be used as a forage replacer for horses – they must be low starch and ideally, nutritionally comparable to forage to be suitable
- Feeding insufficient forage replacer, and therefore fibre, in the diet increases the risk of digestive issues including colic and loose droppings. It is also likely to result in weight loss too
- A minimum of 1.5% of bodyweight on a dry matter basis should be provided daily when totally replacing the usual forage ration. For a 500kg horse this is 7.5kg dry matter and given that many forage replacers are around 90% dry matter this equates to 8.3kg of forage replacer as fed – if you struggle with these calculations – and you’re not alone if you do – contact the Dengie Feedline for help
- Forage replacers for horses can’t usually be fed in a net and instead should be fed in a large wide bottomed bucket. Putting a football or some large, smooth pebbles on top of the bucket can help to slow the rate of intake
- Like all dietary changes a forage replacer should be introduced gradually into the ration over the period of at least a week to ten days.
- One of the first concerns many horse owners have about feeding forage replacers is meal size. It is appropriate to leave large meals of fibre based feeds for your horse to eat just as you would a net of forage. It is only cereal based feeds that that need to be fed in restricted amounts due to the relatively high levels of starch they contain.
- Soaked feeds should be made morning for night and vice versa to keep them fresh and any hay replacer not consumed within the day should be discarded.
Want to know how good your forage is?
The only way to know what your forage is contributing to your horse’s requirements is to carry out a nutritional analysis. It is possible to carry out tests on your hay before and after soaking if you are concerned about WSC levels.
Which forage replacer for my horse?
A range of ingredients are used to provide chopped fibre which are summarized in Table 1. They can be divided into legumes (alfalfa and sainfoin) grass and straw. The grass in chopped fibres is usually dried with hot air and so it is harvested when it is much younger than grass harvested to make hay. This means grass based chopped fibres are much more digestible and nutritious than hay. If a chopped fibre product contains hay it should refer to it as hay rather than grass as there are important differences between the two.
Straw used in chopped fibres is usually dust-extracted and so cleaner than using big-bales direct from farms. Straw used in products made by BETA NOPS approved companies is sourced from farmers who are aware of NOPS, poisonous plants etc and understand the specific requirements for horses.
Alfalfa and other legumes such as sainfoin are a great way of adding essential amino acids such as lysine and counteracting the shortfalls in other types of forage. This makes them ideal for including in forage replacers for veterans and performance horses.
It is very important to consider that any forage replacer that is based on grass will contain more sugar and WSC than those that are predominantly based on alfalfa or straw – assuming other ingredients used are comparable. When sugar declaration are made on chopped forages it is important to differentiate between simple sugars and water soluble carbohydrates (storage sugars). There is no legal requirement to declare WSC values unless specific claims are made about WSC and so it is worth checking the WSC value with the supplier.
Table 1 summarises some of the pros and cons of different types of chopped fibre
| Alfalfa (other legumes including sainfoin) | Grass | Straw |
| Provides a relatively high amount of energy but with very low levels of starch and sugar | Higher in sugar and WSC than alfalfa which helps to make it very palatable but not as suitable for those that need low sugar diets | Low in starch and sugar but low in energy too – ideal for good doers |
| Precision dried so very clean – ideal for the performance horse or horses with RAO | Precision dried so very clean – ideal for the performance horse or horses with RAO | Sun-dried so better suited to leisure horses although can be soaked or steamed |
| Increases amount of chewing when added to the bucket feed – more saliva is produced the more the horse chews so helps to counter negative effects of feeding cereal based feeds such as increased acidity in the stomach | Less structural fibre than other chopped fibres so doesn’t stimulate as much chewing and saliva production | Slows the rate of intake more than other chopped fibres – helps to reduce insulinaemic response to other feeds |
| Naturally abundant in calcium – good for hooves and acts as a natural buffer to acidity in the gut. | Contains less calcium than alfalfa so not as good a buffer | Much lower levels of calcium and other minerals. May require more supplementation of essential nutrients if used at higher levels in the diet |
| Can only be used as partial hay replacer unless mixed with other fibre sources | Can be used as partial or complete hay replacers for horses with problems such as diastemata | Can be used at up to 50% of the forage ration with no increased risk of gastric ulcers. A really useful ingredient to provide more fibre for less calories for good doers |
| Good digestibility which means horse can access the energy it contains easily | Good digestibility so energy readily available to horse | Less digestible and so provides less energy |
Why feeding chopped fibre matters
The amount of saliva produced when a horse chews, is related to the amount of force the horse needs to apply (Vervuert, 2012). So more fibrous materials help to increase saliva production and therefore more natural buffering in the digestive tract than softer ones. Whilst mashes and pelleted fibres contribute fibre, they don’t require as much chewing and so do not generate as much saliva. This phenomenon is supported by a very recent study that found unmolassed sugar beet pulp mash resulted in a greater drop in pH (increase in acidity) in the horse’s mouth than other feed materials including alfalfa and haylage, which the authors suggest could be related to the fact it requires less chewing (Daniels et al, 2024). Whilst the level of acidity returned to normal within 15 minutes and so doesn’t represent a cause for concern in the context of dental health, it demonstrates the importance of chewing for saliva production which has benefits further along the digestive tract.
However, if a horse or pony can no longer manage short chopped fibre then the next step is to move to pelleted fibres that can be fed soaked to make them easier to chew. It is possible to maintain horses on this type of feed with fresh pasture indefinitely as long as they are able to consume sufficient quantities to maintain their health and condition. In these scenarios Grass Pellets or a high fibre cube make great bases to the ration and then a proportion of sugar beet and alfalfa pellets can be added to increase the energy content of the ration if needed.
