Fructan content of grass, hay and haylage should be considered when assessing suitability of forages for horses and ponies affected by laminitis and metabolic disturbances.
It’s been proposed that fructan content of forages can be ignored for horses and ponies affected by equine metabolic syndrome (EMS), laminitis, insulin dysregulation (ID), obesity and PPID.
There seems to be two reasons for this, both of which are flawed:
It is possible that fructan does contribute to insulin response in some individual horses or ponies (see the technical note for references). There is no good evidence that it does not affect insulin response. Therefore, assumptions should not be made.
Furthermore, there is no evidence that pasture-associated laminitis – or that caused by hay high in sugar and fructan – is caused solely by insulin dysregulation. It may be due to a combination of insulin dysregulation and hindgut disturbance from excess intake of fructan.
The research to date does not prove either way whether or not high fructan intake could be associated with laminitis. Much of the research has been undertaken using purified inulin, a type of fructan which is different to that found in grass. Research should be interpreted with great care and its important to bear in mind that results only apply directly to the situation of the particular trial and may not relate directly to the real-life situation.
In future it may well be possible to be more accurate in how to feed horses and ponies affected by laminitis and metabolic disturbances. For the time being, however, using NSC is the accepted method of ensuring the diet is suitable for a horse or pony with ID. NSC covers sugar, starch AND fructan.
In conclusion, it is too early to conclude that grass fructan does not contribute to equine pasture-associated laminitis (includes that caused by hay/haylage intake) and other metabolic disturbances. It is both foolhardy and detrimental to horse health and welfare to ignore forage fructan content for laminitis predisposed or metabolically challenged animals until further research increases our knowledge and understanding.