SCIENTIFIC PROCEEDINGS. 



Abstracts of Communications. 



Sixty-eighth meeting. 



Zoological Laboratory, Columbia University, May iq, IQI$- 

 President Lusk in the chair. 



109 (1041) 



Studies of urinary and blood nitrogen curves after feeding in the 



dog. 



By O. H. Perry Pepper, M.D. and J. Harold Austin, M.D. 



[From the John Herr Musser Department of Research Medicine, 

 University of Pennsylvania.] 



The following studies were designed to show the hourly varia- 

 tions in the normal dog of the total non-protein nitrogen of the 

 blood compared with the output of urine and of the nitrogen in 

 the urine and the effect upon these of various diets and of varia- 

 tions in the water intake. 



Eight dogs have been placed on a diet consisting of meat, 

 lard, sugar, sodium chloride, bone ash and water adequate in 

 calories and containing about 0.4 gm. of nitrogen per kilo of body 

 weight. On the sixth day the ration was varied to suit the study; 

 in dogs 2 to 6 being richer in nitrogen, while in dogs 7, 8 and 9 no 

 food was given on the days of the study. The water intake was 

 varied as shown in the table. On the day of the study the animals 

 were catheterized at intervals of two to four hours and at the time 

 of each catheterization 5 c.c. of blood was taken from the jugular 

 vein for estimation of the non-protein nitrogen by Folin's method. 

 The urinary nitrogen was estimated by Kjeldahl. The results 

 are shown in the table. 



Conclusions. — The daily variation in the non-protein blood 



179 



