568 



EXPERIMENT STATION RECORD. 



[Vol. 40 



The check steer was slaughtered and the feeding experiment started Febru- 

 ary 25, 1908, when the animals were from 9 to 12 months old. The feed was 

 the same for each group, the amounts being varied. Corn chop and linseed meal 

 (8:1) was given twice daily, while cut alfalfa hay to the extent of 40 per cent 

 of the giain ration was fed each evening. One animal of each group (Nos. 591. 

 597, and 593) was slaughtered September 1. In November a digestion experi- 

 ment was conducted with the remaining animals. It was found that the steers 

 in the higher planes of nutrition made more efficient use of all the organic 

 nutrients. The second submaintenance steer was killed January 18, 1909, and 

 the second maintenance steer February 22, 1909. The remaining supermainte- 

 nance steer was sold at this time as he was noticeably fatter than a year before 

 and a gain of a half pound a day had obviously been in excess of bis normal 

 growth. Some of the data derived (com these animals have been discussed by 

 the authors in another connection (E. S. It., 33, p. 569). 



Measurements of 22 body dimensions were made monthly on the animals so as 

 to get a record of changes in the skeletal framework. An accurate outline of 

 the contour at the heart, paunch, and flank girths was secured at intervals by 

 means of a specially devised aluminum chain of adjustable links provided with 

 set screws. 



Tallies give complete data for each animal as to f i consumed every 10 days 



and its chemical composition, the body weights every 10 days, the body dimen- 

 sions ever] month, and the weight ami chemical composition of eacb ol the 



organs and pan- of the body at the time of slaughter. 



Some answer to the questions raised bj the statement of purpose of the experi- 

 ment is given in the following selection of the anther's data : 



Calculated changes >» chemical composition of steers under different mainte- 



nance conditions. 



Steer 



No 602... 



No. ''"1... 

 No 



No 



Chant;? 

 In live 

 vrelghl 



day. 



Lb. 



-0 60 

 - .46 



+ .07 

 + .53 



Feed- 

 ing 



period 



188 



188 

 188 



F.ntin- animal. 



M 

 tare. 



Kb. 



-16 I 



fin .3 

 _ i e 



+ 13. 5 





+ in ,i 



Fro- 



toin. 



Kg. 

 -in 9 

 - 3 9 



-t- .1 



+ 3.1 



Adipose 



Mois- 

 ture, 



Kg 



- "• t 

 -1.0 



- 5 



+ 1.9 



Fat. 



.: 9 



- l.\ 



+ 6 S 



I -can flesh. 



Mois- 

 ture. 



Kb 



+ 7 5 

 - 56 

 + 6.9 



Fv 



Kg. 



-86 



+ 5 



Skeleton. 



Mois- 

 ture. 



Kg. 

 + 10.3 

 • 11 



+ 2 

 + 1.4 



Fat. 



Kg. 

 -4 9 

 + 1.6 

 + 16 

 +2.9 

 +2.2 



Ash. 



K« 



+ 21 

 +2.04 

 + .57 

 +1.53 



From the data Of steer 583 it is concluded that his normal rate of growth was 

 not in excess of bis actual Increase In weight. 



"Wlcn large amounts of fat are used by the animal as a source of energy 

 to supplement a limited food supply some of this fat is replaced by water. 

 . . . When young beef animals in good condition are put on a ration in- 

 sufficient to provide for B normal growth there is a very persistent tendency 

 POW In spite of the feed restrictions. Much of the surplus fat will be DSSd 

 for energy, and growth of both lean flesh and skeleton will continue. Later, 

 with continued U'v<\ restrictions, the animate Will draw on both the residual fat 

 Supply Of the SOfl parts ami also on the protein of the soft parts to maintain 

 existence and to promote a normal growth of the skeleton, which even includes 

 the Storing Of fat in the .skeleton. As the fat supply of the soft parts becomes 



more serious); depleted, and when tim animal has drawn heavily on the protein 

 structure of the sofl parts in order to preserve existence, the animal is ah 



