Some have their horse or pony grazing on the grass 365 days a year without problems, while others are horrified at the thought of putting the horse on grass in winter. Because how dangerous is grass in the winter or can you graze horses in frost without any problems? Read more about that in this blog.
Not every soil is suitable for grazing all year round
The choice to put your horse on the grass during the winter period does not only depend on whether this is dangerous or not. Other things can also be a reason not to keep your horse on the grass in the winter. In the Netherlands, the main reasons for this are wetness and lack of space. Most horse owners do not have enough grassland to house horses there for 365 days. But in addition, the Dutch autumn and winters are relatively wet, which means that especially the clay and loam areas have problems in the winter period. Wetness makes meadows slippery, impassable or completely plowed up by the horse’s hooves. Many horse owners then (understandably) choose not to offer outdoor grazing in the winter.
What happens to the grass in winter?
As soon as the soil temperature drops below 5 degrees, the grass will stop growing. Grass can therefore continue to grow for a long time in mild winters. The grass will store the sugar that is available and not used for growth as fructan. Fructan is a carbohydrate that is produced by the grass under the influence of sunlight.
If the temperature and conditions are such that the grass can grow again, the grass converts the fructan back into usable sugars for the grass. These conversions happen all day long. But during frost (certainly below -5 degrees) sugars are converted to fructan, this fructan then protects the grass against freezing. So in frost there is more fructan in the grass. Fructan is mainly found in the lower part of the grass, which is close to the ground. This is the part where the growth takes place and therefore needs to be protected.
Fructan is digested differently than sugars
Enzymes in the stomach and small intestine break down sugars and starches. But fructan is mainly digested in the colon. Bacteria in the colon ensure the breakdown of fructan and this releases volatile fatty acids. These volatile fatty acids are an important energy source for horses. But an overkill of fructan causes the colon to acidify, releasing endotoxins that poison the horse. These endotoxins can damage the intestinal wall and thus end up in the blood. These toxins increase the risk of laminitis. This is why it is important to keep an eye on the fructan content of the grass, even in winter.
How about that? When is the fructan high and when low?
- Cold, gloomy weather = normal
At low day and night temperatures and no sun, the grass does not grow and no fructan is produced. In this case there is a storage of fructan in the grass, but the values will not be high.
- Cold, sunny weather = high
On a sunny, winter day, a lot of fructan is produced but not used for growth. These days give an extremely high fructan content in the grass.
The higher the temperature, the more the grass consumes fructan to grow. After a night frost and radiant weather during the day, there will be an extremely high fructan content in the morning, but it will decrease during the day.
Tips for safe grazing in winter
- Make sure that the grass is not short, because the fructan is stored in the bottom part of the grass
- Keep an eye on the Fructan index and do not let your horse graze on a sunny day after night frost because the fructan is extremely high.
- Ensure a healthy weight for your horse / pony
- By giving nettle or a detox during the season you keep the blood vessels, kidneys and liver clean so that the toxins are removed.
- Choose a grass mixture that is suitable for horses, so more herbs and various types of grass. Ryegrass is most sensitive to high fructan levels.