930 



ANNUAL REPORT OF THE 



OfE. Doc. 



3 



The cows leeeiviug this ration are assumed to weigh U7U pounds. 

 Other things being equal, the heavier the cow the more food she will 

 need. The standard ration gives the amount of food required for a 

 cow weighing 1,00U pounds. Therefore, in order to compare this 

 ration with the standard it has to be reduced by dividing by .970. 

 This quotient gives the amount of digestible food that would be re- 

 quired for a cow weighing 1,000 pounds on the same basis. It will 

 be seen that it does not contain as much total dry matter, protein, 

 carbhydrates and total digestible matter as the German standard; 

 but more fat and the nutritive ratio is wider. 



HO^A^ TO CALCULATE THE NUTRITIVE KATIO AND TOTAL 



DIGESTIBLE MATTER. 



If we burn a pound of coal we know that there is a certain amount 

 of heat produced. If this heat be applied to water there will be a 

 given quantity of the water converted into steam. Compress this 

 steam and we get power by which we can run a threshing machine 

 or lift a weight. 



If we burn protein, carbhydrates or fat we will also get a certain 

 amount of power if the heat is applied to water. We will assume 

 that the burning of one pound of protein will produce enough power 

 to lift one pound one foot from the ground. The carbhydrates have 

 about the same power; but the power produced by burning one 

 pound of fat is two and one-fourth times as great. That is to say, 

 on the same basis, we multiply the amount of fat by two and one- 



