70 A STUDY OF FARM ANIMALS 



abundant, according to age and condition. Old animals 

 always contain more than young ones, and those that are 

 fat less than those that are lean. Usually we find a little 

 over 3 pounds of ash for each 100 pounds of body weight. 

 A fat, corn-fed hog, however, may be so short of ash in the 

 body that the bone will hardly be strong enough to support 

 its weight. The ash in the animal is made of the same sub- 

 stances as that found in plants. 



The protein of the body is to be seen in the form of 

 muscles, tendons, blood, nerves, the internal organs, hide, 

 hair, horns, etc. Lean meat with no fat on it is protein, or 

 nitrogenous material. The fatter the animal, the less the 

 percentage of protein in the body. In the entire body of a 

 farm animal under usual conditions we find about 13 or 14 

 per cent protein. In the dressed carcass, ready to be sold 

 for meat, we find about 17 per cent. 



The fat of the animal body is composed of carbon, hydro- 

 gen, and oxygen, or of the same chemical substances as the 

 fat of plants, but differing in combination. The amount of 

 fat in the body depends much on how an animal has been 

 fed. If we take a young growing pig, the body may contain 

 only 25 per cent of fat, or even less, but a hog that has been 

 well fattened and is ready for the butcher may contain over 

 40 per cent. Not often do we find less than 6 per cent of 

 fat in the body, or over 35 per cent. In the carcass ready 

 for cutting up in the shop, we find about 20 per cent of fat, 

 under usual conditions. 



Carbohydrates in the animal body are but contained in 

 it, not a part of it, and so this substance can not be regarded 

 as a constituent of animal flesh. Carbohydrates, however, 

 exist in the body in two forms; one, glycogen, similar to 

 starch in composition, found in the liver and muscles; and the 

 other, lactose, or the sugar of milk, found in milk. Dex- 

 trose, another form of sugar, is also found to a slight extent 

 in the blood and tissues. 



