Yearlings are a funny bunch. Gangly and half-grown they’re at that gawky stage where hips are higher than withers and where legs seem all knobby knees and hocks. Sometimes it seems that designing a correct feeding program for them is almost as awkward as the yearlings themselves. You want your youngsters to achieve their maximum height and full athletic potential–but you don’t want to overdo the nutritional support and create all sorts of growth-related problems. What’s an owner to do?

Feeding yearlings actually follows many of the same principles you applied the previous year when these same youngsters were weanlings. The main difference is that while they still have quite a bit of growing to do the rate at which growth proceeds has slowed somewhat. Horses achieve about 90% of their full height by 12 to 15 months of age as well as 95% of their mature bone length and 70% of their adult weight. The remaining growth happens more gradually over the next few seasons. (Some breeds mature more quickly than others of course; many Quarter Horses have pretty much finished their growing by the time they’re 2 1/2 while some warmblood and draft breeds still have significant filling out to do even in their fourth or fifth year.)

Because the growth rate has slowed there is less risk of developmental joint problems; if your yearling hasn’t developed them by now it’s likely that with continuing correct nutritional support he’s out of the woods.

Still it’s important to design your program for your youngster’s optimum growth–not necessarily his fastest growth. Studies have confirmed that a fast growth rate will not increase the mature size of a horse and it puts undue strain on developing bones and joints. Instead your goal should be to achieve a steady growth rate from birth to maturity avoiding any severe growth depressions or spurts by maintaining a good balance of nut