CHAPTER II 



Properties and Composition of Poultry Feeds 



What Cheny.stry Finds in Feeds Peculiar Properties and Uses of Cereal, Vegetable, Animal, and Mineral Feeds 

 Profitable Use of Commercial Mixtures and Condimental Feeds Table of Analyses and 

 Nutritive Values of Feeds of All Kinds Explanation of Mathematical 



Calculation of Rations 



WHILE it is chiefly the nutritive elements in 

 feeds that concern the poultry feeder, most of 

 the whole feeds and many of the by-products 

 contain a considerable percentage of indigestible matter. 

 The presence of this in a feed is often immaterial, as far 

 as the results of using the feed are concerned, but may 

 considerably affect the cost. Some indigestible matter is 

 positively injurious, while some may be beneficial under 

 certain circumstances. These points have to be considered 



in connection with 

 the articles to 

 which they apply. 



Chemical analy- 

 sis of feeds finds 

 in them a great 

 many different in- 

 gredients, but in 

 the ordinary dis- 

 cussion of matters 

 relating to f e e d- 

 ing, these are con- 

 sidered in the few 

 groups to one or 



NEVER TOO YOUNG TO BEGIN TO t h e other of which 

 LEARN POULTRY FEEDING , r , u 



each of the sep- 

 Note equipment to suit scale of _ rof i 



operations a lard pail for mixing arat 



feed, an old milk pan for the water m a v be assigned 



which the boy has learned ducks must 



always have with their feed. These are pro- 



tein, carbohy- 



diates, fats, ash, and fiber. Mention of the functions of 



these was made in the preceding chapter. Here we have to 



consider their character more particularly. 



Protein The most familiar example of nearly pure 

 protein is the white of egg, which contains no carbohy- 

 drate, just a trace of fat, and about one per cent of ash 

 with about seven times its bulk of water. This is of 

 peculiar interest in a study of poultry feeding because in 

 the results of the process of incubation we see a mmure 

 germ, quickened into life by the continuous application of 

 a suitable degree of heat, grow to a perfectly developed 

 chick, by a mode of assimilation of the tissue-forming 

 material which the albumen of the egg provides. The 

 solids of lean meat and blood are about ninety per cent 

 or more protein. In milk the protein is in the form of 

 casein. Pure, dry protein is a hard, horny substance; and 

 in grains the hardness of the grain depends upon the 

 amount of protein. 



Carbohydrates The apple and potato are the com- 

 mon food articles which contain the highest percentages 

 of carbohydrates, and the lowest of both protein and fat. 

 The white potato is almost clear starch. In the sweet 

 potato a part of the carbonaceous material is in the form 

 of sugar. In the common grains the amount of starch 

 varies from fifty to seventy per cent. Grains and seeds 

 which contain large amounts of oil are those in which a 

 considerable part of the common proportion of starch 

 takes the form of fat. 



Fats The familiar pure fats used in human food are 

 10 



butter, lard, oleomargarine, and the various vegetable 

 oils. The common grains contain relatively small percent- 

 ages of fat, running from about two per cent in wheat, 

 barley, and rye, to five per cent in oats, and five to eight 

 per cent in corn. The poultry feeds having the highest 

 percentages of fat are the meat by-products, beef and 

 pork scrap, which may contain as high as thirty to forty 

 per cent of that element, and cottonseed and linseed 

 products, which have the same wide range of fat content. 



Ash The common ash or mineral matters in feeds 

 are phosphates of lime, soda, potash, etc. Chemistry finds 

 some mineral matter in all feed articles, and some of the 

 grasses and forage plants contain high percentages of it. 



Fiber The fiber in feeds is generally indigestible, 

 and consideration of it in a study of feeding deals mostly 

 with the question of the effect of the fiber in an article 

 upon its palatability, and its possible irritating effects 

 when too much is taken into the digestive system. The 

 fibers are largely carbonaceous in character, though lack- 

 ing in nutritive quality. Oat hulls are the most familiar 

 form of fiber in poultry feeds. 



Vitamines Besides the five classes of food elements 

 just described, investigators in food research have re- 

 cently demonstrated the presence in most food articles in 

 a natural state, of certain elements of great importance in 

 nutrition which have been called vitamines. The chemical 

 nature of these has not yet been satisfactorily determined. 



AN OCCUPATION FOR DECLINING YEARS 



This man, when he became too old to work at his 

 regular trade, built a small poultry plant at the edge 

 of the woods, and with about two hundred hens and the 

 chickens raised to keep up the flock kept the wolf from 

 the door in his old age without working beyond his 

 strength. His feed pail is larger than that of the boy 

 above, but his work and equipment are not "on a busi- 

 ness footing." 



