By Dr Vicki Glasgow
Forage, whether in the form of hay, haylage or grass, should be the major contributor to all horse’s diets. The horse’s digestive system is designed to process forage and lots of it, the make-up of the horse’s digestive system points to what his diet should consist of. The stomach is less than 7% of the empty weight of the gut in equines. It has a small capacity and it can only cope with small meals because of the inelastic property of the wall. The small intestine comprises 30% of the digestive tract with around 60% of the horse’s digestive capacity being in the large intestine (caecum, colon and rectum) that contains large microbial populations (good bugs). The main function is to achieve microbial fermentation of fibre in the ‘hind gut’. This is why horses are categorized as hind gut fermenters. The way that the horse’s digestive tract is designed means that, in order to maintain correct digestive tract function, horses must receive a minimum of 1% of their body weight daily as long-stem fibre. This is an absolute minimum and 2%-2.5% would be more appropriate in the majority of cases.
Quality and quantity
Since forage makes such a large contribution to your horses’ diet the quality of it can have a major effect on your horse’s condition. If you have a horse that struggles to hold condition over the winter then investing in good quality forage can make an enormous difference. Unfortunately, it is impossible to tell the energy value of hay by looking at it. It is possible to have hay analysed for energy value before you buy but it is only really worthwhile if you are able to buy a large quantity from the same field, to do most of your winter. If not, then the only way of telling is by whether your horse holds condition well on it or not. Haylage is mostly a better bet if you are after high energy forage, although some haylages can be lower nutritional quality than good hay. Haylage is generally of higher nutritional quality, however, due to the fact that it is generally cut earlier in the year and is usually cut from high sugar grass variety swards (e.g. rye grass). Remember to feed more haylage on a weight basis than you would of hay as approximately 40% of it is water as compared to the 20% for hay. Feed about one and a quarter times as much haylage as hay, and make sure that your horse is not standing for hours on end with an empty haynet as this can lead to digestive upsets and behavioural problems. Remember to also introduce haylage gradually, if your horse is used to hay, making the swap over period over at least a week.
Good doers
Good doers can have the opposite problem if the hay quality is too good. Some hay can be very high in energy and if this lands in a yard with mostly good doers then it can cause problems. This type of horse should be losing weight during the winter months and if the forage is especially good the owner will struggle to make this happen. Especially when also faced with reduced exercise and turnout time. If faced with this situation there are a few options. The first is to try to find a different source of hay. Look for hay that has been cut late and looks coarser and more fibrous, also look for hay that has a higher percentage of timothy grass rather than rye grass. This will hopefully mean that there are less sugars in the hay and, therefore, less energy. As stated above, however, this is no guarantee and analysis is the only way to know for sure.
Soak away
Another option, and possibly the safest is to soak hay for good doers to leach out the majority of the sugars. This should be done for 4 hours minimum and preferably 12 hours. This can become a difficult task once the frost etc comes in but as long as it is soaked when weather permits it will make a difference. If you have an insulin resistant horse then it is best to try to find a low sugar hay. This is because, if it proves difficult to soak the hay for weeks on end, it will have an effect on this type of horse as it is each meal that the horse eats that is important rather than the accumulative calorific intake, which is so important for fatties. Many good doers will survive on just their forage portion with some minerals (in the form of a powder or lick) or a feed balancer, which makes for a cheap winter. Don’t feel the need to give a fatty a big bucket of feed that it doesn’t need just because his neighbours are receiving a big feed 2-3 times a day. As mentioned in previous columns winter is the time to shed pounds off this type of horse so feeding should be kept to a minimum.
Shortages
If you think that getting adequate baled forage is going to be difficult, or you know you have a horse that is prone to condition loss, then it may be pertinent to replace some of your hay requirements with bagged chops. Rather than waiting until you are short on hay and then be forced to rely entirely on chopped forages, it would be better to start replacing some of the hay portion in the early part of the winter. Chops will replace hay on a weight for weight basis and can be selected according to the type of horse you are feeding and the amount of work it is doing. Feed the chop separately from the normal concentrate feed and leave the bucket for the horse to pick at as he pleases along with his haynet. There may be some problem with horses eating these too quickly, in which case some rounded stones or a football in the chop bucket will slow them down a bit. Products such as alfabeet, sugarbeet etc can be used in the bucket feed to boost energy intake and fibre provision, and of course the use of high oil, high fibre feeds will help to keep condition on.
Long stem Fibre
From a digestive health angle it is best to provide your horse with long stem fibre of some description which is why it is best to use bagged chops to replace some of the hay portion and not all. Remember that last year’s hay, as long as it has been stored well and (if you can get a hold of some) will still have the same energy value etc as it did, it will just be lacking in vitamins. Oat straw can also be used if hay and haylage become scarce but again it is best not to let hay run out and have to rely entirely on it. Good doers can make best use of oat straw, with the hay being saved for those who need it. Remember that oat straw may also be in short supply and a wet harvest period can result in mouldy straw too.
Be prepared
For this year it will be wise to be prepared and buy as much forage in advance as you can store. Bear in mind that any forage purchased is going to have to last you for at least 12 months, possibly longer. Better to overestimate than under and you will probably use more hay than you think over next summer too. Also remember the best way to provide fibre to you horse is via grazing. If you can, find winter grazing for your horses and keep them out for as many hours as you can. This will help ease the strain on your hay/haylage stocks and also keep your horse fitter as an added incentive.