THE NUTRIENTS AND NUTRITION 317 



Bacteria and Digestion. — It is probable that bacterial 

 action is responsible for a part of the digestive process, though 

 studies of the bacterial flora of the digestive tract have not 

 proceeded far enough to give a great deal of accurate infor- 

 mation on the subject. While there is no opportunity for 

 microorganisms to break down crude fiber and make it 

 available, as is done in the rumen (paunch) of the ruminants, 

 the work of Schottehus (as reported by H. J. Wheeler') 

 seems to show that they enter very markedly into the 

 digestive processes. He hatched chickens from eggs which 

 were free from foreign organisms, in germ-free air, and fed 

 them on sterilized food, only to have them die in two to three 

 weeks. If hatched in the same manner and fed unsterilized 

 or normal food the chickens hved. Other chickens fed like the 

 first until near death were saved by feeding normal chicken 

 feces or unsterilized feed. This work was done before 

 anything was known concerning the vitamins and it is jios- 

 sible that tliese may have been a factor in the result. 



Disposition. — In comparing fowls with other farm animals, 

 besides the anatomical differences, there is a decided difference 

 in disposition. Birds are more active, have a higher tempera- 

 ture, and more rapid digestion. As a rule, six months 

 represents the age of maturity and four or five years the life 

 period. 



With these things in mind it is easy to see that all of the 

 body processes must be extremely rapid. The relation 

 between feed and these productive processes, while no closer 

 in point of composition than is the case of other domestic 

 animals, in point of time is very much closer. 



The result of wrong feeding is more quickly disastrous 

 than with any other class of stock, and for the same reason 

 that breakage is likely to be more serious in a high-geared 

 as compared with a low-geared machine, the disaster caused 

 by wrong feeding, particularly during the growing period, 

 is more likely to be so serious as to be permanent. With 

 slower-growing animals there is more opportunity for 

 recovery and repair. 



' Rhode Island Bulletin No. S4. 



