10 The Bulletin. 



Every feed dealer, to ])rotet't liimself and liis trade, should insist on 

 feeds being shipped him in strict compliance with the law. If he will 

 do this and nV)t buy from those manufacturers who do not comply with 

 the law, he will save considerable trouble and inconvenience by having 

 his feeds seized and confiscated by feed inspectors. 



THE CHEMISTRY OF FEEDS. 



In the chemical analysis of feeds the following determinations are 

 made : protein, fat, fibei-, nitrogen-free extract, moisture and ash. With- 

 out going into a detailed description of the chemical properties of these 

 classes of substances, the following general discussion will be found val- 

 uable in interpreting the analysis of commercial feeds : 



PROTEIK. 



The term protein or crude protein as used in feed analysis includes all 

 the nitrogenous compounds contained in the feed. These compounds are 

 divided, chemically, into two classes — the true proteins and the amide 

 compounds. Familiar examples of the true proteins are the white of 

 egg, lean meat and the gluten of flour. In seeds and cereal products the 

 amido compounds are present in very small amount, and hence all the 

 nitrogen is regarded as present in the form of protein. The protein 

 compounds contain, approximately, 16 per cent of nitrogen, so to de- 

 termine the amount of protein in a feed the total amount of nitrogen is 

 determined, and this, multiplied by the factor 6.25, gives the amount of 

 protein. 



The protein compounds are of very great importance in feeds, for it 

 is from them that the animal derives the nitrogenous materials from 

 which its muscular tissues are built. 



FATS. 



Fats, or more ])roperlv termed ether extract, include all the substances 

 soluble in dry ether. These substances include the pure fats, such as 

 cotton-seed oil, inseed oil, etc., and the waxes, resins, chlorophyl, etc. In 

 most feeds the waxes and resins are present in such small amount that 

 the entire ether extract may be regarded as fat. In a few feeds, such as 

 alfalfa ])roducts, the ether extracts the chlorophyl or green coloring 

 mat(er of the plants. This amounts to only a small per cent. 



CRUDE FIBER. 



'I'hc term crude fiber includes the woody parts or the structural ma- 

 terials of ]dants. It is composed largely of cellulose and is the most in- 

 digestible part of the feed. As a rule, a feed Avilh a high percentage of 

 fiber is considered to be a low-grade feed. 



MOISTURE. 



Water is present to sonic extent in all classes of feed. Hays and com- 

 mercial feeds usually contain fioni 6 to If) ])er cent of water. 



