Dry summer leaves grazing short — nutritionist urges careful forage planning

A prolonged dry spell has left grass growth poor across much of the UK, and many horse owners are already feeding hay at a time of year when they would normally rely on grazing. Speaking to Your Horse, Dr Katie Williams, technical and product development manager at Dengie Horse Feeds, has set out practical advice for managing forage when both quantity and quality are hard to come by.

One of her central points is that you cannot judge a hay's sugar content by eye. Coarse, fibrous, later-cut hay is likely to be lower in calories, but that does not make it low in sugar — and hay made in bright, hot conditions is likely to be higher in sugar regardless of how it looks. This matters particularly for horses and ponies with insulin dysregulation, who are generally recommended forage below 10% non-structural carbohydrate. In hot summers, Dr Williams notes, hay analyses have regularly come back above 20%, and in some cases above 30%.

Soaking reduces some sugar but is inconsistent, and she advises against long soaks in hot weather. Diluting hay with straw is the more reliable option: straw is high in fibre and very low in calories, takes longer to eat, and can be introduced gradually up to 30–50% of the forage ration. Chopped fibre feeds — many straw- or legume-based — can replace hay weight for weight. She also flags a quieter risk in a drought year: when pasture is dry and sparse, intakes of trace minerals and vitamins such as vitamin E fall, so a broad-spectrum supplement or low-calorie balancer may be needed. As always, owners with concerns about a particular horse's condition should speak to their vet or a qualified nutritionist.