5-4 MAINE STATE COLLEGE 



2nd. They call for a larger proportion of protein in the ration of 

 the milch cow than in that of the somewhat mature steer. 



"We believe that the experiment under discussion gives evidence 

 that tends to substantiate this opinion. 



THE INFLUENCE OF THE RATIONS UPON THE COMPOSITION OF THE BOD- 

 IES OF THE STEERS. 



When this experiment was planned it was determined to undertake 

 the somewhat arduous task of making a chemical analysis of the en- 

 tire bodies of the experimental steers, the purpose of this costly 

 piece of work being to determine whether the composition of their 

 bodies was materially modified by the proportions of nutrients in 

 the food. This plan was carried out and the organs and carcasses 

 of the four animals were analyzed, the only part omitted being the 

 skin and hair. These are believed to be the only fairly complete an- 

 alyses of the bodies of mature bovines since those made by Lawes 

 & Gilbert nearly forty years ago, whose results were published in 

 1S58. 



Separation of parts, sampling and analyses. When the steers were 

 killed the blood was caught in a tub which was set under a small 

 trap door in the floor. The animals were then dressed and the 

 various organs and parts were weighed as soon as removed, the 

 carcasses being also weighed in the green condition. 



The various organs and divisions of the body were taken to the 

 laboratory and sampled for analysis as rapidly as the work could be 

 performed. It was not over forty-eight hours after the animals 

 Avere killed before the samples of all the various parts were secured 

 and in the process of drying. 



The manner of obtaining the samples was as follows: In the 

 case of the organs such as the heart, liver, lungs, &c, they were 

 minced very fine by being - run through a power Enterprise Meat 

 Chopper. This minced material was thoroughly mixed and then 

 large samples were selected for drying. The flesh of the right side 

 of each carcass was entirely removed from the bones, the muscular 

 tissues and the adipose tissues being separated mechanically as fully 

 as possible and thrown into separate dishes. Both the lean portions 

 and the fat were entirely passed through the meat chopper, large 

 samples being selected from each portion for drying. The lean meat 

 samples were dried and the samples of fat were bottled without dry- 

 ing in air tight jars and kept very cold until analysis. The intestinal 

 and kidney fats were treated in the same way as the body fat. 



The samples were brought to an air-dry condition in a drying clos- 

 et heated by a coil of steam pipe, the temperature of which varied 

 from 50 to 60 degrees C, or 120 to 140. degrees F. 



The air-dry samples were finally prepared for analysis by passing 

 them through a mill. The samples of fat which were enclosed in jars 



