PRINCIPLES, METHODS AND SYSTEMS OF FEEDING 



29 



LARGE COLONY HOUSE, COOK AND FEED HOUSE, AND DOUGH CART ON 



RHODE ISLAND POULTRY FARM 

 The cook house is built to drive the cart through to load. 



feeding of other animals. They soon discovered that the 

 foundation of the science of poultry feeding was in the 

 practice of the best poultrymen. The fact that a ration 

 adjusted by careful trials in practice to get certain re- 

 sults did produce those results, showed that it was a 

 properly compounded ration. 



When the rations used at that time by the best poul- 

 trymen were analyzed and their values computed according 

 to the proportions of the different nutritive elements each 

 contained, it was found that the most efficient grain and 

 meat rations for growing stock and for heavy egg pro- 

 duction had very nearly the same proportions of protein 

 to carbonaceous 'elements that is found in wheat, barley, 

 and rye. The average for a number of good rations com- 

 puted by the writer at that time was precisely the same 

 as for barley. As computations of this kind do not take 

 into account the green feed consumed, which in ordinary 

 practice cannot be measured or weighed with sufficient 

 accuracy to include its values in the computation of the 

 rations used, they are hot scientifically accurate, yet they 

 are sufficiently so for common use. Before describing the 

 method of making such computations it is necessary to 

 explain the common scientific terms used in dealing w'th 

 feeding and with feed values. 



It has been shown that the common grains, and the 

 mixed rations as worked out by the best practical poultry- 

 men before the days of scientific study of poultry feeding, 

 contain the relative proportions of protein and of carbo- 

 i aceous materials which poultry require under average, 

 ordinary conditions, and that with variations from those 

 conditions, or to secure extraordinary results, the relative 

 proportions of the different classes of feed elements are 

 increased or diminished as the case requires. This rela- 

 tion between protein or flesh-forming elements, and car- 

 bohydrates and fats (the heat and energy producing ele- 

 ments), reduced to terms of carbohydrates by multiplying 

 by 2.25 is called the nutritive ratio, or nutrient ratio. 



Each natural whole article of feed 

 has a nutritive ratio which is con- 

 stant to all intents and purposes of 

 practical feeding. In the straight mill 

 products of grains the ratio is also 

 constant, but in by-products of vari- 

 able composition it also is variable, 

 of course, and that is wjay the neces- 

 sity arose for official inspection and 

 analysis of such products. In mix- 

 tures of any number of ingredients, 

 the nutritive ratio for the mixture is 

 computed by first computing the total 

 amount of each of the principal feed 

 elements contained in it and then 

 finding the ratio of the protein to 



the carbonaceous matter, the fat being reckoned at two 

 and one-fourth times the value of the carbohydrates. 



For simplicity and convenience of comparison, nu- 

 tritive ratios are commonly expressed in their lowest 

 terms, and as the term representing the protein is always 

 the smaller one, the protein is always represented by 1. 

 An article or mixture in which the difference in the 

 numerical values of the terms representing the relation of 

 its protein to its carbonaceous elements is small is said to 

 have a narrow nutritive ratio: One in which the differ- 



PERHAPS THE MOST POPULAR STYLE OF CART IN 



THE LITTLE COMPTON COLONY POULTRY 



FARMING DISTRICT 



The low platform makes it easy for the feeder. The 

 barrel and box are movable, and the cart can be used for 

 many purposes besides feeding. 



THE DOUGH CART SEEN IN UPPER PICTURE 

 This cart has the mash box and water barrel accessi- 

 ble at the tail, a deep box for grain in the middle of the 

 frame, and a coop for moving chickens in front a 

 complete equipment. 



ence is relatively great is said to have a wide nutritive 

 ratio. An article, mixture, or ration having a narrow 

 nutritive ratio is therefore a relatively highly nitrogenous 

 feed, while one having a wide ratio is relatively a highly 

 carbonaceous feed. To make a ration narrower is to in- 

 crease the amount and proportion of its protein; to make 

 it wider is to increase the amount and proportion of its 

 carbohydrates or fats, or both. 



Early investigators and students of feeding subjects 

 generally regarded the nutritive ratio as the best measure 

 of value of a feed. On the assumption that flesh-forming 

 elements were more essential they reasoned that the 

 higher the proportion of these an article contained the 

 greater was its feeding value, and if they did not ex- 

 pressly state it, their statements still conveyed to most 

 persons not versed in the science the impression that the 

 more protein in the feed the better the results would be. 

 It was customary to compute the values of feeds in terms 

 of the heat units they contained and to give these with 

 the nutritive ratios, but the fuel value, or potential energy, 



