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of silage and maize fodder the digestibility is higher after glazing or denting than before:
Digested from One Hundred Parts Organic Matter.1
Armsby2 found that the total digestible food of the fully mature crop was from two to three times as great as the same variety in the silking stage and thirty-six per cent greater than at the time the ears were glazing.
353. Influence of Maturity Upon Feeding Value.—The Pennsylvania Station3 and the Ohio State University4have determined the feeding value, when fed to milch cows, of equal areas of maize fodder when cut in the roasting-ear, silage stage, and when ripe or nearly so. In both cases the food value from equal areas measured in milk produced and increase or decrease of live weight was greatest in the intermediate stage. Compared with the earlier cutting, the intermediate stage gave much the best results, while compared with the late cutting, the difference was. not so marked. The weight of field cured fodder increased with the stage of ripeness, the increase being greatest during the first interval. The percentage eaten, the fodder having been prepared with a feed cutter, was least in both instances in the early cut, greatest in one case in the medium cut and in the other instance in the late cut.
1 W. H. Jordan: The Feeding of Animals, p. 212.
2 Penn. Rpt. 1892, p. 23. s Penn. Rpt. 1892, p. 34.
♦ D. A. Crowner, Thesis, 1896.
II. USES AND PREPARATION FOR USE.
354. Food for Domestic Animals —The chief use of the maize crop is as a food for domestic animals. In connection with grass it is the meat producing material of the United States. The wonderful development of our pork industry is directly related to our maize crop. Sir John Lawes once said that the natural food of the civilized hog was barley meal. Had he lived in America, he would have said that the ears of maize are the natural food of the civilized hog. Maize silage forms an important element in the production of dairy products and its grain is largely used as a food for horses.
The food value of the grain of maize lies in its high net available energy due to its high percentage of easily digestible carbohydrates and fat and the absence of any deleterious substance. The plant other than the ear, whether green, ensiled or dry, is a palatable and healthful food for horses and ruminants, the dry matter being more digestible than that of timothy or clover hay. When properly prepared, the food value of the dry matter is rather less, and when the grain is added, rather more than that of timothy hay. The digestible nutrients in the grain and stover are about as two to one. The proportionate food value, however, is greater in the grain on account of its greater net available energy.
355. Food for Human Consumption.—While of less relative importance as a food for man, the actual amount of maize thus used is large. In the Southern States, where the proportion of maize to wheat grown is larger than in the Northern States, the grain of maize forms a large portion of the dietary of all classes. The meal, prepared by simply single grinding, either bolted or unbolted, is made into various forms of bread and cakes, without yeast or other leavening processes. Compared with products of wheat flour, the products of maize meal are less digestible, probably on account of the hull and the coarser grinding. They are in every way, however, healthful and desirable articles of diet.
Hominy is prepared in the household by soaking the grains in the lye of wood ashes (KHO), which removes the hull, and also by hominy mills, which remove the hulls by a milling process. In the milling process of producing hominy the germ is more or less completely removed, thus adding to the keeping quality of the hominy, but somewhat lowering the per cent of protein. The maize grain is also used in some of the so-called breakfast foods other than hominy. These are low in protein and fat and high in carbohydrates, as compared with maize grain or meal, or with breakfast foods made from wheat or oats.
The ears of sweet maize are boiled when the grain is in the milk and eaten out of hand, forming a well-known and palatable article of diet. Experiments have been successfully conducted at the New Hampshire Station1 in raising sweet maize under glass in order to furnish roasting ears out of season. "Canned corn," made by removing the grains of sweet maize when at this stage, placing in quart cans and subjecting to high heat, both before and after sealing, is the basis of an extensive industry. The mature sweet maize is also eaten parched.
356. Manufactured Products.—Glucose, starch, alcohol, whisky and malt liquors are also made from the grain of maize. Two forms of "corn starch" are made, one used in laundry work to stiffen cotton cloth and the other used for human consumption. The pith of the stems is used in the manufacture of explosives and for packing the sides of war vessels because of its property upon being pierced of quickly swelling and preventing ingress of water. The stems are used in the manufacture of paper and the husks for mats and mattresses.
357. By-Products.—The use of the maize plant in the manufacture of the above products has resulted in a large number
1 N. H. Gul. 60 (1899).
of by-products. This is especially true in the manufacture of starch and glucose, where oil (262), gum, dextrine, rubber substitutes, germ oil meal, gluten meal, bran and gluten feed (mixture of gluten meal and maize bran) form important byproducts. Distillers' grains are a by-product in the manufacture of alcohol, spirits and whisky and brewers' grains in the manufacture of beer. (466) Both distillers' and brewers' grains usually contain a mixture of several grains, commonly maize, barley and rye. Over twenty million bushels of grain, mostly maize, are used annually in the distilleries of the United States. The annual output of distillers' dried grains exceeds forty thousand tons and is largely exported to Germany for cattle feeding.
"There are quite generally three grades made, one from the distillation of alcohol and spirits, a second from the distillation of bourbon whiskey and a third from that of rye whiskey. The first named is the higher in feeding value, and is most apt to be of even quality, corn being the main, and, sometimes, the only grain used. The other grades vary in their composition in proportion to the relative proportion of corn, rye and malt used in the mashes; the more the corn and the less the smaller grains, the better the grade of the product." 1
Gluten feed and distillers' and brewers' grains form accept able foods for milch cows where large percentages of protein are required, and germ oil meal is especially desirable for calves and pigs where higher percentages of ash and fat unaccompanied with fiber are desirable. The by-products of glucose and starch factories are obtained by mechanical processes and the composition of each is rather uniform. The by-products of distilleries and breweries are the result of fermentative processes and may vary considerably in composition. Hominy feed is a by-product in the manufacture of hominy and differs from the original grain principally in containing a larger proportion of hull and embryo. The by-product in the manufacture of "cerealine" breakfast foods is known as cerealine feed.
1 Vt. Rpt. 1903, p. 238.
When the pith is removed for the manufacture of explosives or packing for war vessels, the remainder, which may or may not include also the husks and blades, is ground into a coarse meal and is sold as "the new corn product." The Maryland Station1 found it more digestible than timothy hay, for which it was successfully used as a substitute in feeding horses.
The following table gives analyses of by-products of maize used as food for domestic animals: