Digestive Coefficients of Poultry Feeds, etc. 
'21 
The portion of the distillate caught at 105 degrees to 110 degrees C. was saved as 
piperidine. 
The distillate caught between 105 degrees to 110 degrees C. was very strongly al¬ 
kaline to phenolphtalien and caused uric acid to dissolve, decolonizing the phenol- 
phthalein color. 
DISCUSSION 
The constituents of mammalian urine are classed as organic and inorganic. The 
chief organic constituents are nitrogenuous end products—urea, uric acid, hippuric 
acid, creatin, and creatinin; aromatic compounds—benzoic acid, etherial sulphates of 
phenol, cresol, and small amounts of animo acids, allantoin, purin bases and coloring 
matter and mucous 8 ; salts consisting of sulphates, phosphates and chlorides of sodium 
potassium, calcium, and magnesium. 
The total nitrogen of the urine consists of urea nitrogen, uric acid nitrogen, ammonia 
nitrogen and creatinin nitrogen. 
Creatinin is hydrolized creatin. It has been generally considered that creatinin of 
the urine arises from the creatin of the muscles. In alkaline urine creatin appears 
in greater quantity while the reverse is the case with strongly acid urine. 9 
Urea originates in the body partly from retrograde tissue metamorphosis, includ¬ 
ing the blood, and partly from splitting up of unassimilated nitrogenuous principles 
of the food. 
Uric acid in birds is formed in the liver from ammonia compounds and lactic acid. 
It is formed from the splitting of nucleoproteins 10 . These nuclein bodies are compounds 
of protein with nucleic acid, the latter constituent splitting up into thymic acid and 
derivatives of purin among which is uric acid, xanthin, hypozanthin, etc. 
The ammonia salts present in urine are an index to the neutralization of acids in 
the body. The acid substances are produced as the result of metabolism. When they 
are in excess there is an increase in the ammonia of the urine, the formation of am¬ 
monia in the muscles being the natural protection of the body against acid poisoning. 
Hippuric acid is a product of herbivora. 
Nanthin is contained in human urine. 
Brown says that the nitrogenuous substances of birds’ urine, aside from ammonia 
urate, are present in exceedingly small quantities. In fact it must be borne in mind 
that the creatinin, hippuric acid, purin bases, etc., are present in mammalian urine 
in relatively minute quantities, and this is conspicuously brought out when the amount 
of such extractives are'calculated per kilo weight. Hence the urine of animals of so 
low a body weight as poultry would contain in all probabilities but minimal amounts 
of such exactives if present at all. In view of these considerations veiy large quanti¬ 
ties of excrement would be required to demonstrate the presence of such bodies. 
Meissner, in 1861, found in hens fed on meat the urine yielded creatin but no crea¬ 
tinin. Only minute amounts were eliminated by the grain-fed birds, and in many 
cases its presence could not be satisfactorily demonstrated. Liver-fed hens produced 
less than those fed on meat When creatin was given hypodermically it was practical¬ 
ly all recovered as such in the excrement. He claims that two to four percent of the 
urinary nitrogen is urea. He did not find hippuric acid in the uiine of hens. 
Milroy says that urine of hens may contain in very small quantities purin bases. 
8 Smith, Col. F., Veterinary Physiology, p. 292. 
9 Purdy, Practical Urine Analysis, p 36. 
10 Webster, Diagnostic Methods, p 218. 
