COMPOSITION OF FEEDING STUFFS. 217 



which are found in the body of the animal Itself, although the 

 components in the two cases are rarely identical, but can be dis- 

 tinguished from each other in most cases by certain chemical re- 

 actions. The animal body through its vital functions has the 

 faculty of changing the various food substances which it finds in 

 the food in such a, way that they are in many instances different 

 from any substances found in the vegetable world. 



The components of feeding stuffs which are generally enumerat- 

 ed and taken into account in ordinary chemical fodder analysis, or 

 in discussions of feeding problems are: Water (or moisture, as It 

 is often called), ash materials, fat (or ether-extract), protein, fiber, 

 and nitrogen-free extract; the two components last given are 

 sometimes grouped together under the name carbohydrates. These 

 components are in nearly all cases mixtures of substances that 

 possess certain properties in common; and as the mixtures are 

 often made up of different components, or of the same compon- 

 ents In varying proportions, it follows that even if a substance is 

 given in a table of composition of feeding stuffs, in the same quan- 

 tities in case of two different feeds, these feeds do not necessarily 

 have the same food value as far as this component alone is con- 

 cerned. 



Water or moisture is found in all feeding stuffs, whether succu- 

 lent or apparently dry. Green fodders contain from 60 to 90 per 

 cent, of water, according to the stage of maturity of the fodder; 

 root crops contain between 80 and 90 per cent., while hay of dif- 

 ferent kinds, straw, and concentrated feeds ordinarily have water 

 contents ranging between 20 and 5 per cent. 



Ash or mineral matter is found in all plant tissues and feeding 

 stuffs. We find most ash in leafy plants, or in refuse feeds made 

 up from the outer covering of grains or other seeds, viz., from 4 to 

 8 per cent.; less in the cereals and green fodder, and least of all 

 In roots. A fair amount of ash materials is a necessity in feeding 

 young stock and pregnant animals, and only limited amount of 

 roods low in ash should be fed to such animals; refuse feed from 

 starch and glucose factories which have been treated with large 

 quantities of water should, therefore, be fed with care in such 

 cases. 



Fat or ether-extract is the portion of the feeding stuff which Is 

 dissolved -by ether or benzine. It is found in large quantities In 



