i6 COMPOSITION OF THE ANIMAL BODY 



the lower is the percentage of water, because- fatty tissue 

 contains less water than lean tissue. In the body of the 

 extra fat sheep the per cent of water may run as low as 35, 

 while in the body of the store sheep there is about 57 per 

 cent of water. This is one reason why the butcher pays 

 the best price for the fat animal. 



Vitamines. — Until the last few years it was supposed 

 that any feed containing proteins, fats, carbohydrates, and 

 mineral matter combined in the proper proportions was a 

 perfect feed. It has been recently discovered, however, 

 that there are two other substances, called vitamines, 

 whose chemical nature is at present unknown, which are 

 necessary to life, growth, and reproduction. One of these 

 substanres is found in milk, unpolished rice, peanuts, 

 kidney beans, and some other products. Since it is easily 

 dissolved in water it is called water soluble vitamine. The 

 other substance, found in butter fat, beef fat, cod-liver oil, 

 margarines, leaves of cabbage and alfalfa, and in some seeds, 

 is called fat soluble vitamine. Both vitamines are present 

 in whole milk, cotton seeds, soy beans, kernels of corn, oats 

 and wheat, and certain other plant and animal products. 

 Young animals fed on feeds from which the vitamines have 

 been removed fail to grow or even to live, and older animals 

 fail to reproduce. The practical apphcation of this dis- 

 covery is to be found in feeding milk containing some but- 

 ter fat to all young growing animals and in curing and stor- 

 ing hay and other roughage in such manner that' their life- 

 giving vitamines will not be washed away by dew and rains. 



What Becomes of a Feeding Stuff in the Body of the 

 Animal. — It has already been shown that there is a close 

 relationship between the materials in the plant and in the 

 animal body. The food materials in the plant, when eaten. 



