New York Agricultural Experiment Station. 



57 



In Period 1 with Cow 12 the amount of digested protein was 

 large, about 2.6 lbs. daily, and in Period 3 it was only 1.6 lbs. 

 The decrease in ingested protein caused a marked decrease in 

 urine nitrogen. In Period 1 the heat value of the urine was 

 equal to 19.1 Cal. for each gram of nitrogen present, and in 

 Period 3, 30.9 Cal. This simply means that the less the nitro- 

 gen compounds present, the larger the relative quantity of other 

 substances. We must conclude, then, that the loss of energy in 

 urine cannot be calculated from any constant factor but must be 

 determined in every particular case. 



Heat Energy of the Nutrients in Several Periods. 



Total Cal- Total Cal- 

 ories in dry ories In dry Total Cal- 

 matter matter ories in 

 Periods. consumed. of feces. urine. 



Coic 12. 



1st Period,! 



days .... 396017.9 129879.6 11623.2 266138.3 254515.1 224S29.3 

 2d Period, 7 



days 399765.8 136032.9 10S81.2 263642.9 252761.7 222024.4 



3d Period, 8 



days .... 45032G.2 162177.0 105S4.0 288149.2 277565.2 242683.3 



Goto 10. 

 Feb. 4-10, 10 



days .... 448583.6 127231.3 14525.1 321352.3 306827.2 273199.8 



We have now reached a point in the development of our data 

 where we can see what they teach concerning the unit heat 

 values of the nutrients utilized by these two animals. From 

 the figures of the two preceding tables the unit values given in 

 the succeeding table were calculated. 



Heat Values Based on a Unit gf^One Gram. 



