

FUNCTIONS OF NUTRIENTS 39 



The pig has only a very limited power of dealing with 

 fibrous foods. 



Mineral Matter or Ash. Lime, magnesia, and 

 phosphoric acid are important constituents of the 

 bony skeleton of animals ; hence if the food given 

 to animals is poor in bone - forming minerals, the 

 supply is so small that the animal, in addition to 

 being undersized, has bones which are diseased in 

 some way or other (e.g., rickets in pigs). Pregnant 

 females also require more lime, etc., to supply this 

 constituent for the bones of the foetus. According to 

 Prof. Henry, the animal skeleton may act as a reserve 

 storehouse for mineral matter, and, when the supply 

 in food is below requirements, dole out lime, phos- 

 phates, etc., in order that the various functions of the 

 body may be maintained, e.g., dairy cows may at times 

 give more lime in the milk than is supplied in the 

 food. 



Potash is found chiefly in the muscular tissues of 

 the body, while soda is an important constituent of 

 blood and the digestive juices. In the stomach sodium 

 chloride (common salt) is partly converted into hydro- 

 chloric acid, which renders the gastric juice acid. 

 Common salt (NaCl) has the power of dissolving some 

 of the albuminoids ; it also improves the palatability 

 of some foods, and increases the flow of digestive juices. 



According to Kellner, the chlorine as well as the 

 soda of common salt is required for dairy cows, because, 

 if omitted altogether, the cows gradually become weaker 

 and may ultimately collapse, but if chloride of sodium 

 or potash is added to the food, they quickly recover. 



Water. Water is indispensable in the animal body, 

 for without water there can be no life, seeing that it 

 is an essential constituent of the living matter (proto- 



