When first introduced into this country it was used somewhat extensively by omnibus companies and in other large horse establishments, on account of its low price in comparison with that of oats, for which it was substituted. By the Paris Omnibus Company it is reported to have been found to be equal in digestibility to an equivalent quantity of oats. Experiments made in the army, as recorded by Colonel F. Smith, were not altogether favourable, as it appeared that in whatever proportion it was substituted for oats, there was a diminution in muscle and energy. Five thousand two hundred army horses were fed, in Austria, partly on maize for six months, and it is stated that, although they improved as regards their coats, they lost energy and sweated profusely at work. It is said to be largely used in America and South Africa for feeding purposes, and it does not appear that in those countries the objections which have been raised to its use as a substitute for oats exist, at least they have not been mentioned.
Maize contains less nitrogenous matter than oats, but it is extremely rich in fat and also in salts. It is difficult to masticate on account of its extreme hardness, and it is, therefore, absolutely essential that it should be submitted to some sort of preparation before being used, even if it is intended to be mixed with other food. The difficulty of mastication is, to some extent, disposed of by crushing. This process is certainly indispensable. Without it it is hardly possible that maize could be digested, even by ruminating animals. An opportunity occurred lately of noting the condition of this grain in the digestive organs of some deer, which were fed on mixed food in addition to the grass which they consumed. The mixture consisted of chaff, with chopped roots and maize uncrushed. A considerable number of the animals died during the season, after wasting. There was no reason, however, to suspect that they had suffered from indigestion; in fact, it was ascertained that they died from parasitic disease; but it was noticed that the maize, even in the fourth stomach, had escaped the action of the digestive fluid, as well as the action of the teeth, and remained as perfectly intact as though it had been brought from the store, instead of being taken from the stomach. In fact, a portion of it, after being washed and dried, presented quite the ordinary appearance. The test may be taken as a crucial one, as the grain had been macerated in the first compartment of the deer's stomach, re-masticated during the process of rumination, passed through two other compartments of the stomach, and finally, in the fourth compartment, had been subjected to the action of the gastric juice.