The various food-stuffs used for horse provender in these days of cheap and rapid transport are drawn from a great portion of the habitable world. This wide extension of the sources of supply has naturally led to a large increase in the kinds of food-stuffs used, and the different sorts of oats, beans, peas, maize, barley, bran, linseed, hay, etc, imported into the country are daily increasing.
The old plan of feeding with oats and hay stood the test of experience very well, but economy could not be disregarded, and in most large studs an extended and more varied bill of fare is now the custom. But it is not solely to economic considerations that this change is due. It is not difficult to understand that no single food, however admirable, can provide for a horse's requirements in the same degree as a well-proportioned mixed food will do.
The term "mixed food" is generally used to signify a mixture of various grains with chaff.
In forming such a mixed food several points have to be considered, as no mixture can be the best for all horses under every circumstance. A food suitable for old horses may be inappropriate for young growing animals, and, generally speaking, the class of horse, his condition, his work, the season of the year, will all influence the amount and proportions of the various food ingredients.
In discussing food and feeding it is usual to give tables showing the chemical constituents of the various food-stuffs, but it is not intended to give in detail data of that kind in this section. (See, however, the chapter on Foods, page 87 of this volume). Nevertheless it may be pointed out that in employing such data, when deciding the most appropriate mixture for horses under any given circumstances, certain points must always be remembered. No comparisons can be fully relied upon between unlike substances. To accept analytical composition as a true estimate of the respective values of fodder and grain would be absurd. Their real value depends upon the constituents that are digested, and not upon their relative component constituents, and as the amount of digested constituents in any food is materially influenced by the food materials with which it is given, the necessity for knowledge in the amalgamation of food is very evident. Under the plan of feeding with oats and hay, the custom is to give a certain measure of oats and allow hay in the rack ad libitum; but in the more economic plan of using mixed food, a definite weight of hay is apportioned to a definite weight of mixed corn. In deciding the proportion of grain to hay it may be observed that no large bulk will compensate for defects in quality, and no concentrated mixture for deficiency in quantity. Much of the saving effected by mixed feeding has been by a partial substitution of grain for hay, and in this connection it may be remembered that a bulky food is particularly unsuitable for horses on account of the small size of the equine stomach. And when grain can be obtained at a less price per ton than hay, as is nowadays frequently the case, there is a natural inclination to increase the less expensive but more nutritious grain and reduce the more expensive and less nutritious hay; but this substitution can only be carried to a certain limit, and any attempt to go beyond this will prove disastrous.
It must not be forgotten that a too highly concentrated food is very dangerous for any horse, and particularly so for greedy feeders. These, being unsatisfied with a deficient bulk, are tempted to overgorge whenever the opportunity occurs, and as highly concentrated cut food favours rapid mastication, gastric repletion is soon established with all its attendant evils. On the other hand, as has been pointed out, the equine stomach is ill adapted for bulky innutritious food, and horses fed on such food are deficient in the condition and fitness requisite for long-continued and severe exertion. It is of real importance, therefore, both in the interests of efficiency and economy, to apportion accurately the weight of hay to the weight of mixed grain, as well as to decide upon the most suitable grain mixture.
Practical experience teaches that hard-worked horses will do well upon a mixture of two parts hay and three parts grain, and that it is not advisable to reduce the quantity of hay materially below this, and is uneconomical to increase it materially; but while such a mixture meets the requirements of horses doing hard work, it is an unsuitable and too rich a food for idle horses, for which a mixture of equal parts of chaff and grain will answer much better.
Chaff is simply cut hay, or cut hay mixed with a proportion of cut straw.
A very good and not too expensive chaff will be secured by mixing together two parts meadow hay, one part rye-grass and clover, and one part good oat straw.
In forming a suitable grain mixture, it should be remembered that the chief characteristic of cereals is the large percentage of carbohydrates in them, and that although oats may be used alone, both they and barley are improved by the addition of a few beans. While cereals are characterized by the large proportion of carbohydrates they contain, the percentage in maize is still greater; and therefore, while the addition of beans is beneficial with cereals, it becomes almost essential with maize.
As has been observed elsewhere, whenever a horse food is deficient in nitrogenous elements the deficiency is most easily made good by the addition of beans; and moreover beans, although so valuable in a mixture, are, in consequence of their highly nitrogenous character, altogether un-suited for use alone.
By bearing these points in mind, and by the confirmation of practical experience, a good and economical grain mixture can easily be made; and it has been established that a suitable mixture for working horses is obtained by combining two parts cereals, two parts maize, and one part beans.
Whatever plan of feeding is followed the food-stuffs used should be the best of their kind. Hay and straw should be the produce of good soils, and should be sweet, clean, well-harvested, and free from mould.
Corn should be clean, hard, dry, and sound, and old corn as a rule should be preferred to new, as it is less likely to give rise to any gastro-intestinal derangement.