Mar. 25, 191S Energy Values of Feeding Stuffs for Cattle 



467 



Table IX. — Heat production per day and per head corrected to 12 hours standing — Con. 



Feeding stuff and experi- 

 ment No. 



Alfalfa hay and grain 

 mixture No. 2; 



208. 



209. 



Mixed hay and maize 

 meal: 



Mixed hay and hominy 

 chop: 



Animal 

 No. 



E 

 E 



E 

 C 

 C 

 F 

 F 

 F 



{e 



Period 

 No. 



Corrected heat produc- 

 tion. 



First 

 day. 



Cats. 



7.434 



5.940 



5. 032 

 6,802 



6, 096 

 9.679 

 7.645 

 6,791 



8,678 

 14. 510 



9,782 

 14,877 



Second 

 day. 



Cats. 

 7.532 

 5.9" 

 5.138 

 6,927 

 6, 149 

 10, 099 

 7,809 

 6,659 



8,362 

 14, 467 



10, 126 



15.040 



48-hoiu' 



Cals. 



7.483 



5.924 



5.084 



6,858 



6,123 



9,888 



7. "5 



6,734 



8,470 

 14. 561 



9.947 

 14,936 



Analysis of heat production. 



Stand- 

 ing 12 

 hours. 



Cals. 



916 



788 



824 



I, oil 



1,043 



1. 132 



844 



948 



1.505 

 2,852 



1,695 

 1,850 



Rising 

 and 

 lying 



down. 



Cals. 

 56 



53 

 35 

 31 

 34 

 89 



73 

 68 



74 

 68 



71 

 102 



CHj 

 fer- 

 menta- 

 tion. 



Re- 

 main- 

 der. 



Cats. 

 464 

 303 

 165 

 388 

 284 

 562 

 382 

 253 



470 

 I, 126 



64 

 I, 216 



Cats. 



6,047 



4,780 



4, 060 



5.428 



4,762 



8,10s 



5,816 



5.465 



6.421 

 10.515 



7,538 

 11,768 



As already stated, we estimate the experimental error in the deter- 

 mination of the heat emitted by the animal to be approximately i per 

 cent. In the 73 cases in which a comparison of the two days can be 

 made, 40 show a deviation from the mean of the two 24-hour results 

 of less than i.i per cent — i. e., the results for the two days practically 

 agree within the limits of experimental error. Of the 53 experiments^ 

 made since 1905 — i. e., experiments 200 to 212 — which, in our judg- 

 ment, are, on the whole, more accurate than the earlier ones, 36 fall 

 within this limit or error. On the other hand, however, deviations as 

 great as 2 per cent are not uncommon, while occasionally they rise to 

 as much as 5 per cent or even 7 per cent. The mean of the percentage 

 deviations is for the entire series 1.45 per cent and for experiments 200 

 to 212, inclusive, 1.13 per cent. Moreover, the deviations of the single 

 days from the mean are, on the whole, fully as great after reduction to 

 12 hours standing as before. It is clear, therefore, that despite the 

 apparent uniformity of experimental conditions the metabolism of the 

 animals was affected by influences other than the feed or the propor- 

 tion of time spent standing. 



Mr. H. H. Mitchell, of the Illinois Experiment Station, has had the 



kindness to submit these data to mathematical study and finds that 



they present clear evidence of the existence of individual differences 



between the animals as regards the agreement between the two days. 



He writes as follows: 



It seems very evident to me lx)th from inspection of the data and from statistical 



calculations that tlie percentage deviation of duplicate determinations of the heat 



78745°— 1; 



