Hard keeper

A hard keeper or (British English) poor doer is a horse or other animal that is naturally prone to be thin, will lose weight quickly, and has difficulty gaining weight.

A horse that is too thin is not necessarily a hard keeper. The animal may be ill, elderly, or has not been provided adequate nutrition. Whenever a horse is too thin, it is well-advised to have a veterinarian give the horse a thorough examination and recommend the best course of action.

The opposite of a hard keeper is an easy keeper (good doer); an animal that can live on relatively little food and is prone to obesity and other health problems associated with a too-rich diet. In contrast, a truly hard keeper is almost never fat under any circumstances.

It is extremely rare for a pony or a donkey to be a hard keeper. The condition is most often seen in light horse breeds that have either a naturally high-strung temperament or breeds that tend to a very lean phenotype and are then subjected to stressful conditions. Breeds with a higher percentage of hard keepers include race horses such as the Thoroughbred, and certain types of show horses bred for style and animation, such as the American Saddlebred.

It is natural for a normal horse to require more nutrition to avoid weight loss if it is pregnant, lactating, under stress due to illness or management conditions, or when subjected to hard work. With a normal horse, adjusting the animal's diet to compensate for the conditions it is facing will usually return the animal to its normal condition.

If an animal is truly a hard keeper, proper nutrition requires a calorie-rich diet, but one that will not make the horse "hot" and prone to excess energy that may lead to yet more nervous behavior and continued weight loss. Forages that are highly nutritious and calorie-dense, such as alfalfa and beet pulp are often recommended. Concentrated feeds that are high in fat but low in carbohydrates, such as rice bran, ground flaxseed, or corn oil are often added to a basic grain or pelleted feed ration to assist weight gain without creating excess energy. High-energy feeds containing significant amounts of sugars, such as molasses, are not usually recommended because they have a tendency to make a horse "hot" or more excitable. However, in cases where a hard keeper also has work with high energy requirements, such as horse racing, an extra, but carefully balanced source of energy may be necessary.

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