Nutritive Ratio. — By nutritive ratio is meant simply the proportion 

 by weight of the digestible carbohydrates and fnt, to the pro- 

 tein, the latter being taken as unity. It has been demonstrated 

 by experiment that, other things being equal, the best returns 

 can be secured in case of milch cows for example if the various 

 feeds are so combined as to produce a ration containing 4.5 to 

 5.5 as much carbohydrates and fat, as protein, or in other 

 words rations having a nutritive ratio of 1 protein to 4.5 to 

 5.5 carbohydrates and fat (1 :4.5 or 1:5.5.) 



Calculating a Nutritive Ratio. 

 In calculating a nutritive ratio, it is necessary to multiply 

 the amount of fat by "2^ to give it a value corresponding to 

 carbohydrates because the fat furnishes 2^ times as much 

 energy as do carbohydrates. Suppose a fodder ration to con- 

 tain the following amounts of digestible nutrients : — 

 Digestible protein 2.70 lbs. 



" fat 0.73 " 



" carbohydrates 12.60 " 



Total digestible 16.03 lbs. 



According to our definition the nutritive ratio would be 

 found as follows : 



Carbohydrates 12.60 lbs. 



Fat .73 lb.X2i= 1..S2 " 



Total for fat and carbohydrates 14.42 lbs. 

 14.42 lbs. carbohydrates -^ by 2.7 lbs. protein=5.34 or as 

 1 part of protein is to 5.34 parts of carbohydrates (1 : 5.34). 



Organic Matter. — The organic matter of a plant or feed, as the 

 term is used, signifies that pcrt'on, which can be burned, the 

 elementary composition of which is carbon, hydrogen, oxygen, 

 and nitrogen, which in the plant are more or less intimately 

 associated with inorganic elements. 



Oxygen. — Oxygen in its natural state is a gas. When united with 

 other elements it forms many of the most important organic 

 and inorganic substances. 



Pectin. — Pectin is the jelly-forming compound of many fruits. 



Pentosans. — Pentosans are substances found in the woody portions 

 of plants, closely identified with the cellulose. 



Phosphoric Acid. — Phosphoric acid is a combination of oxygen, 

 hydrogen and phosphorus. It is usually found in plants, 

 combined with lime and magnesia and is usually stored up in 

 the largest quantity in the seed. Phosphate of lime forms 

 the principal mineral part of bone. 



Phosphorus is an inoiganic element, being the character- 

 istic ingredient of phosphoric acid. 



