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The nitrogenous matters or albuminoids are considei'ed the most valuable of the 

 nutritive ingredients of a fodder, and in the animal economy play the part of flesh- 

 producers. They enter largely into the composition of muscle and cartilage, and are 

 essential constituents of the vital fluids, blood and milk. They also assist in pro- 

 ducing fat and developing heat and energy. 



The Non-nitrogenous matter is made up of (1) fat, (2) fibre and (3) carbo- 

 hydrates. These are all composed of carbon, hydrogen and oxygen, and their chief 

 function in the animal is the generation of heat and muscular energy necessary for 

 the continuance of life and the accomplishment of work. 



Fat. — Of the non-nitrogenous constituents, fat has the highest nutritive value; 

 and this because it contains a larger percentage of carbon than fibre, or the carbo- 

 hydrates, in the burning of which in the blood much heat is evolved. Its increased 

 value is largely due, also, to the fact that it can be converted into animal fat much 

 more readily than the other organic ingredients. 



Fibre is the least valuable of the food ingredients. It is the part of plants that 

 coriesponds in function to that of the bones of animals, viz., the supporting and 

 'strengthening of the other tissues. By chemical means it can be sepilrated tromthe 

 other parts of a fodder as a fibrous or woody material. As plants mature, the fibre, 

 as a rule, becomes less digestible, chiefly owing to the deposition of ligneous or woody 

 matter. 



Carbohydrates. — These include starch, sugars and gums, and consist of carbon 

 united with oxygen and hydrogen in the proportions in Avhich they exist in water. 

 They servo, by their oxidation to carbonic acid and water in the animal, to produce 

 heat and energy. 



The Inorganic or mineral part is recorded in the column " Ash." It is that 

 part left when a fodder is burned, an operation that destroys and dissipates the 

 organic matter. It is composed chiefly of lime, magnesia, poiash and soda, combined 

 with phosphoric and hydrochloric and silicic acids. The functions of these materials 

 in the animal are to assist in forming bone (largely composed of phosphate of 

 lime) and to furnish that small quantity of mineral matter found in all animal 

 tissues. 



Co-efficient of Digestion. 



The portion of food digested is assimilated and utilized by the animal either in the 

 formation of muscle or fiit or in the production of heat; the portion undigested passes 

 out of the animal us solid excreta. The amounts or percentages, of albuminoids, fat 

 and fibre digested are known as the co-efficients of digestion. Thus, if 75 per cent, of 

 the total amount of the albuminoids in a grass is digested, the co-efficient of digestion 

 of the albuminoids in this fodder is 75. 



The digestion co-elficients of the constituents of a fodder may be all different. 

 We also find thatthe co-efficient for the same ingredient varies according to the nature 

 of the fodder. The two following examples will illustrate these statements. 



Digestion Co-efficients. 



