368 FEEDING WITH SUGAR BEETS, SUGAR, ETC. 



Pea meal comes under the head of the legumes. Its use is not very gen- 

 eral. It may contain 20 per cent, protein and an average of 15 per cent. fat. 

 Combined with roots, it is frequently used in feeding, and then offers special 

 advantages. It excels all split peas. 



Pectic substances. The composition of these products is very var- 

 iable. They are found in beets and other roots in the form of pectose. When 

 boiled this becomes pectin, and if the heating continues, there is formed 

 pectic acid, etc. , which acid is insoluble in boiling water; when the boiling is 

 continued, there is formed a metapectic acid. As these simple and complex 

 bodies are digestible, they play important roles in animal feeding. Just what 

 relation exists between them and carbohydrates remains to be demonstrated; 

 they differ from carbohydrates in their percentage of oxygen. 



Pentosanes are found in considerable quantities in plants. The pen- 

 toses, the outcome of pentosanes, are hydrocarbons. 



Peptones. Constituents found in sugar beets as well as in other roots, 

 etc., and are also formed from protein during the function of digestion. It 

 remains to be demonstrated just what their role is, and, consequently, what 

 advantage there is in having them in fodder. 



Phosphates. Phosphoric acid combines with alkalies to form phosphates. 



Phosphoric acid. In many fodders phosphoric acid is very deficient, 

 and should be added in one form or another. The percentage of this chemical 

 in plants varies very considerably. In beets and residuum cossettes, this acid 

 may frequently be found in sufficient quantity to meet the demands of the bony 

 tissues. 



Plant foods. Plants, during their growth, take up from the soil cer- 

 tain elements, such as nitrogen, phosphoric acid, potash, etc., which are the 

 foods upon which their development largely depends. 



Protein. Represents a compound consisting mainly of nitrogen. Just 

 how it is formed in plants is explained by the action of nitric acid and sulphur 

 upon the protoplasms of the cells of plants. After a certain period, the 

 protein appears to leave a certain portion of the cellular tissue and centers 

 itself in the seed and mainly in the germ. The protein compounds may be 

 divided into two groups, albuminoids and amides; they constitute the most 

 important elements in feeding, and therefore should be the most expensive. 

 The transformation that these protein constituents undergo during assimilation 

 consists in the formation of muscles, bones, skin, etc., which action may be 

 for the purpose of replacing waste, or to help build up and increase tissue. 

 The mode of determining the percentage of protein in any feeding stuff", is too 

 complicated for the present writing. Suffice it to say that after the nitrogen 

 has been estimated, the amount is multiplied by 6.25, and this, for all practi- 

 cal purposes, represents the protein. The amount of protein in feeds varies 

 considerably; 100 Ibs. of clover hay contain 12 Ibs. protein, while sunflower- 

 seed cake contains per 100 pounds nearly 83 Ibs. protein. Between these two 

 there is a long series of fodders. Upon general principles, it may be admitted 



