28 PRINCIPLES OF FEEDING FARM ANIMALS 



and body fluids. Calcium is the most abundant constituent 

 of the mineral matter of the body forming more than half 

 of it. It is found especially in the bones in the form of 

 phosphates. Phosphorus is found also in the active tissues, 

 in the body fluids, and in some of the proteins and other 

 complex compounds. Potassium is found especially in the 

 lean tissues, as the muscles, organs, blood corpuscles, etc. 

 Magnesium is quite generally distributed throughout the 

 body. Sodium, in the form of sodium chloride, is found 

 especialh^ in the body fluids. Sulphur occurs in many of the 

 proteins, especially in wool, hair, hoof, and horn. Inasmuch 

 as the fatty tissue contains only a small amount of mineral 

 matter, the percentage of mineral matter in the animal body 

 varies inversel}^ with the degree of fatness, i.e. fat animals 

 contain a lower per cent of mineral matter than lean ones, 

 and vice versa. Thus the percentages of mineral matter are 

 less in hogs and sheep than in cattle, which ordinarily con- 

 tain less fat. 



Fat. — Under n ormal conditions fat occurs in nearly 

 eve ry organ ^nd "cell of the animal bod\: . It is espec ially 

 abundant in the connective tis sues of^f^ nbrlnrpinnl c-'^vi^v, 

 in the subcutaneous tissues, and in the bone marrow. Large 

 quantities of tat maj^ Be~stored byThe ammal as reserve food 

 material. In fairly mature a nimals in good ^co ndition^ fa t 

 next to water is ordinarily the most abunda nt su bstance of, 

 the animal bodvv . Fat hogs usually contain about 38 per 

 cent, fat sheep about 36 to 46 per cent, and fat steers nbont 

 24 to 38 per cent fat . Thin hogs and sheep contain about 

 20 per cent, and thin cattle about 14 per cent fat. The fat 

 calf and the fat lamb contain less fat than more mature 

 animals of the same species' in similar condition. Other 



