One of the most misunderstood terms in the horse world, in my experience, is “good condition”.
A horse is often said to be in good condition when he is, in fact, merely fat. If someone tells me a horse is in “very good condition”, I tend to want to run a mile, because horses thus described are generally obese.
Obesity in horses is as serious, and nearly as widespread, as in humans. It can lead to a variety of health issues (similar to an overweight person’s), such as laminitis, joint strain, heart problems, equine metabolic syndrome (horse diabetes), lethargy and inability to do even gentle work without considerable discomfort. In fact, obesity is a form of malnutrition, just like starvation. A horse who wobbles all over when you poke it isn’t in very good condition; it’s malnourished. Just not in the way that we usually think of when that term is used.
True good condition comes in several forms, most notably hard condition and soft condition (both terms being somewhat dated by now, but still pretty relevant). Fit horses in moderate to hard work are in hard condition. I personally like my working horses to be a little on the trim side; it is not quite as attractive as a well-rounded horse, but easier on their legs. A horse in hard condition is lean and powerful; he is hard and supple all over, and his muscles are powerful and well developed, especially across the neck, back, loins and hindquarters. The outline of his ribs may be visible when he moves. His musculature means that each part of his body flows smoothly into the next, but all his muscles are well defined. His tummy is tucked up, showing toned stomach muscles, and when he is carrying himself well a line stands out on his side underneath his ribs. This is a kind of horsy six-pack and shows that he’s using his stomach muscles. One should be able to feel his ribs easily when running your hand down his side, but his coat should be shiny and move easily over his bones, and his strong muscles should show that he is far from malnourished.
Horses that don’t do much work – like retired or resting horses or broodmares – are in soft condition. A horse in soft condition is healthy but not fit. His coat is supple and shiny, and he does not wobble when he moves. He may have very little muscle tone and a hay belly (not a worm belly; there is a difference) is likely to be present. However, he is not overweight. He is fatter than the horse in hard condition, but his ribs are easily felt, and there are no thick fleshy pads of fat visible. His body parts join smoothly together, but are still well defined, and he moves around his pasture without effort or heavy breathing. I would say that a horse whose last ribs cannot be felt is significantly overweight, but will add that a broodmare in the latter stages of pregnancy can run slightly fatter. She will lose her excess weight when she foals, and she needs to be in good condition to conceive again. An overweight mare will not conceive well, but nor will an overly thin one.
There is one circumstance where I consider a somewhat skinny horse to be in good condition, and that’s in the case of a young, growing horse – let’s say between six months and two and a half years of age. After weaning, young horses often become a bit ribby, and their owners tend to panic and stuff them full of concentrates. This isn’t necessary, and could even be harmful if one feeds more than 1kg of concentrates per day to a weanling. Have you seen a teenage guy lately? They’re like matchsticks, because, like young horses, they are growing like weeds, usually in spurts. Their food all seems to go upwards instead of sideways. (Wouldn’t it be nice if that happened to all of us?) Once they mature, they’ll bulk out again. It is in fact healthier for a young horse to be on the ribby side. Young bones and joints don’t need to carry excess weight, and a young horse that is fed so much that he gets fat is generally growing too fast, so his bones are likely too soft. Add his excessive weight into the equation and you could end up with permanent damage or weakness in his bones, specifically the legs.