Horses turned out for winter need much more than pasture to keep them in good order. Horses are not ruminants like cattle, sheep or goats, but they do digest fibre and this process generates heat inside the animal. In winter this is especially important.
Winter pasture in most parts of New Zealand is not an adequate feed for a horse - even to maintain its body weight. A 500 kg horse needs about 10kg of Dry Matter to maintain its body functions, and in terms of winter grass, the animal would need to eat around 52kg of good quality pasture in a day.
In most parts of the country this is not available, so supplements of grain and hay are essential. This extra feed cost should be seen as part of the commitment owners make when taking on the responsibility to care for an animal. Winter is the time of extra vigilance to make sure the animal is well fed and cared for.
So on cold days in winter don't forget to feed that extra roughage as well as some concentrates and grain to help your horse keep out the cold.