8 SCIENTIFIC FEEDING OF ANIMALS 



precipitate itself. By this method proteins are 

 isolated from non-proteins, and by using the same 

 factor, 6-25, the amount of either, or both, can be 

 got. 



Dried animal residues, such as meat- or fish-meal, 

 or the gluten of wheat, contain the highest propor- 

 tion of crude protein. Next come various oil cakes, 

 dried brewers' grains, leguminous and oily seeds, 

 whilst hay made from leguminous crops, cereal 

 grains and their by-products follow. Hay made 

 from grass, dried potatoes and green fodders are 

 poorer in protein, whilst, as is seen in the tables 

 in the Appendix, straw and chaff contain least of all. 



(3) Nitrogen-containing substances of non-protein 

 nature. 



These non-protein substances, often called amides 

 or amino compounds, show very great differences 

 in their properties. They all agree, though, in 

 containing nitrogen, but are not of a protein or 

 albumin nature. In this class may be placed 

 ammonia, which is found in small quantities in 

 silage ; asparagine, which is a crystalline substance, 

 first found in asparagus and later in many young 

 shoots and quickly growing green plants ; gluta- 

 mine, an easily soluble substance, which can be 

 got from the beetroot ; and, lastly, lecithine, 

 which resembles fat, and consists of the nitrogenous 

 material combined with free fatty acid, glycerine, 



