372 



VETERINARY PHYSIOLOGY 



tryptophaue in which amido-propionic acid is linked to a 

 pyrrhol-benzene. 



\ 



\ 



C CH 2 .CH.NH 2 .CO.OH 



NH 



\/ i 



Benzene. ; Pyrrhol. \ Amino-propionic Acid. 

 By the breaking down of the amino-propionic acid, skatol 



- C CH 3 



\/' 

 NH 



is formed, and by the removal of the methyl, indol is produced 

 \ -C H 



> /\ / ( 

 \/ \/ 

 NH 



Phenol 



\ _ -H 



CH 



65 



/ 

 \/ 



is a further stage of disintegration. 



By taking embryo guinea-pigs at full time from the uterus 

 and keeping them with aseptic precautions, it has been shown 

 that the absence of micro-organisms from the intestine does 

 not interfere with digestion. 



The most important and abundant organism present in tl 

 intestinal tract is the bacillus coli communis, which has 

 certain power of splitting proteins and a marked action in pro- 

 ducing acids from sugars. Its presence in water is generally 

 indicative of sewage contamination. 



