Forage extenders
By Hannah Botha, MSc Equine Science (Royal Agricultural College, UK), Equine Nutrition Specialist for RCL Feeds
With the effects of winter lingering on, the average quality of hay and grazing is still low. Certain areas of the country have had the compounding issue of a serious drought, but even with no water-supply difficulties, finding good grazing at this time of year is a considerable challenge.
Forage
Forage (hay and grazing) is a vital part of the horse’s diet as it provides a valuable portion of the daily energy requirement and is essentially the food that horses were naturally designed to eat. The greater the quantity of forage eaten by the horse, the less likely it is to need to feed large quantities of concentrates.
Forage also serves to sustain a healthy digestive environment, as well as producing heat during the fermentation process of digestion that breaks it down. This heat production helps to maintain body temperature and aids the horse in staying warm and comfortable in cooler temperatures.
Fibre (a large component of forage) can also increase water intake by the horse, which produces a unique water reservoir in the hindgut which can prevent dehydration and electrolyte loss during hard exercise or in hot climates.
Forage is crucial for maintaining the health of the horse. The average horse requires at least 1.5-2% of their body weight in forage per day. A 500kg horse, for example, would require at least 7.5-10kg of forage per day.
What are forage extenders?
Forage extenders (also known as hay replacers) are designed to replace a portion of the forage in the horse’s total daily diet in times when hay or grazing may be of poorer quality or not available at all.
What forage extenders are currently available?
Forage extenders are available in many forms such as super fibres (soya hulls and beet pulp) or chopped hay options (chaffs and cubes).
- Super fibres are useful fibre additions as they are more digestible than traditional fibre sources and also provide a much higher level of energy per kilogram. This makes them particularly suitable for hard-working horses and those who struggle to maintain weight.
- Soya hulls are the outer coating of the soya bean and are a common super fibre in manufactured feeds. Although highly digestible, soya hulls are not that palatable and not all horses take to them well when fed alone.
- Beet pulp, a by-product of the sugar industry, is far more palatable and is therefore the more widely used super fibre. However, beet pulp is not native to South Africa and is therefore more expensive than traditional fibres. Beet pulp must be soaked prior to feeding, but despite the additional effort involved, this soaking has the added benefit of being particularly useful for horses with poor dentition, as it makes the food easier to chew compared to traditional fibre sources.
Finally, super fibres generally have a low NSC value (sugar and starch level), which makes them ideal for horses suffering from gastric ulcers, laminitis, tying-up and Cushing’s disease, for example. As super fibres are more digestible than traditional forage extenders, they can be fed at slightly lower levels. For example, 0.5-1% of body weight per day would normally be sufficient. For a 500kg horse this would work out to approximately 2.5-5kg per day.
- Chaffs are good forage extenders, however, caution is advised as some chaffs have a coating of molasses which may not be desirable for all horses. Chaffs also don’t provide a daily supply of vitamins and minerals, and so an additional supplement may be needed if no concentrate feeds are fed in conjunction with the chaff.
- Hay cubes are a great solution, as they contain added vitamins and minerals and are therefore more complete than chaffs. The vitamin and mineral fortification is, however, not as high as standard concentrates, making them usable at higher levels if needed or alongside additional feedstuffs. Hay cubes are also an ideal alternative for horses with respiratory problems as they limit their exposure to inhalation of dust. They can also be ideal for horses struggling with inflammatory disorders of the bowel, as long-stemmed hay can irritate the gut. Horses with dental issues particularly benefit from hay cubes as they often struggle to chew and digest long-stemmed hay and chaffs. Hard-working horses can sometimes lose their appetites during competition, leading to a reduced intake of forage. This may expose horses to digestive upsets and lead to underperformance and loss of condition. Hay cubes can be ideal under these circumstances as they tend to be more palatable.
How much can I feed?
The answer to this question is dictated by the circumstances in which the horse finds himself, as horses are all individuals. Contacting a nutritional advisor for help is best; however, the following three points should be considered for the use of forage extenders:
- If the grazing is not of good quality, but the hay is, then the need to use forage extenders is reduced as more hay can be fed to make up for the poor grazing. In these cases, 500g-1kg per day of a hay extender should be more than adequate, especially if concentrates are also being used.
- If hay and grazing are both of poor quality, then 1-4kg per day of a forage extender can be fed together with concentrate feed (if needed).
- If no grazing or hay are available, forage extenders are used as a replacement and can be fed at up to 1% of body weight for short periods of time.
Notes for using forage extenders
Horses are designed to eat small amounts of feed over the whole day. When forage extenders are fed, consumption time is faster as the horse requires less chewing time than he would for long-stemmed hay. It is for this reason that feeding of forage extenders is recommended to be spread out across the day in small meals. This feeding recommendation will also help to avoid boredom.
Due to horses being designed to eat little and often, there is a constant flow of gastric acid within the stomach. In order to buffer this acid flow, saliva is needed. Horses only produce saliva when they chew, and therefore, if left for long periods of time with nothing to chew or if chewing time is reduced, they can be put at risk of developing gastric ulcers. For this reason, forage extenders cannot totally replace long-stemmed hay and grazing for long periods of time. Even if hay and grazing are of little nutritional value, some long-stemmed hay must still be fed to keep the digestive system active and healthy.