pound of starch or sugar it has been assumed that theyd-Zin fod- 

 ders is 2)^ times as valuable as the carbo-hydrates for feeding 

 purposes, consequently in determining the nutritive ratio the fat 

 is multiplied by 2^ and the product added to the carbo-hydrates 

 this has the effect of making: the whole of the non nitrogenous 

 part of the food appear as starch or sugar. An example will 

 best show how this is done. Take the corn meal above tabulat- 

 ed, there are 8.66 pounds of digestable albuminoids; There 

 are of carbo-hydrates (starch, sugar, fibre etc) 65.63 lbs., of fat 

 2.94 lbs., multiplied by 2)^ gives the equivalent of carbo-hydrate 

 7.35 ; the carbo-hydrate equivalent becomes 72.98 ; the ratio of ni- 

 trogenous to non-nitrogenous is as follows : 8.66 to 72.9S, or as 

 I : 8.4. This last is the nutritive ratio of corn meal. The modi, 

 fication alluded to is this: instead of giving the carbo-hydrates 

 and fat in separate columns I shall multiply the fat in each food 

 by2J2 'Xndaddxt to the carbo-hydrates, and give the sum in one 

 column under the term carbo-hydrate equivalence. The reason for 

 this will appear in the practical work of computing rations, 

 under "practical feeding." 



The table last given would be changed to the following : 



.'\lbuminoids. Carbo-hydrate equivalence. NiUrliivc r^tio. 



Corn meal, 8.66 72. 9S 1:8.4 



Shorts, 14-17 51S4 1:3-6 



What are the uses of food in the animal system.-' 

 Having considered what food i.s and finding it made up of 

 parts having unlike qualities it is very natural to ask if the 

 albuminoids and corbohydrates are of equal value, before this 

 can be answered it will be best to see why animals require food. 

 Some of the uses of food may be best explained by comparing 

 the animal to the locomotive. We will take the case of a loco- 

 motive, standing idle in the yard, with the temperature of the 

 atmosphere at zero. Under these conditions heat is constantly 

 being given off to the air, and, if left to itself, after a time the 

 fire goes out, thewater gradually cools off, until it freezes. This 

 tendency is caused by what is known as radiation of heat and 

 the result is that the locomotive and air in time come to the 

 safne temperature. To prevent this, either wood or coal is burn- 

 ed in the fire-box. An ox, standing in a cold barn, or out of 

 doors, loses heat by radiation, just as the locomotive does and 

 is this loss was not made good in some way, it would only be a 



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