VITAMIN C 



171 



day and continue to grow for about 15 days, then lose weight rapidly 

 and die of scurvy in from 26 to 34 days after being deprived of anti- 

 scorbutic food. If the animals are much younger, the results are some- 

 what less regular; if much older, the animals are somewhat less sus- 

 ceptible, and also less likely to show good growth up to the time of 

 onset of scurvy symptoms. 



Symptoms, Survival Period, and Autopsy Findings. — With animals 

 such as have been described, the first symptoms of scurvy appear after 

 about 12 days on the above basal diet. The nature and sequence of 

 the symptoms have been so fully and clearly described by Cohen and 



4^0 



410 



380 



^350 



k290 



230 



200 



6 /2 16 24 

 TIME IN DAYS 



30 



Fig. 7. — Weight curves of guinea pigs receiving basal ration adequate in all 

 other respects but lacking vitamin C. Average curve and curve of one animal 

 showing in pronounced degree the initial loss in weight at the beginning of the 

 experimental period as described in the text. 



Mendel (1918) and by Hess (1920, pp. 135-140) as not to require 

 detailed discussion here. Loss of weight usually begins soon after the 

 appearance of the first symptoms, though some animals begin to lose 

 weight earlier. On the first or second day of the experimental period 

 there may occur a decrease of body weight due to elimination of bulky 

 intestinal contents from the green food of the fore-period. In such 

 cases the minimum weight of the first or second day is taken as the 

 initial weight of the experimental period. As an accurate weight curve 

 is helpful in the interpretation of results, each animal should be weighed 

 at least once in three days throughout the experimental period. Fig. 7 

 shows the average weight curve of 10 guinea pigs kept on the basal 

 diet above described. Since the time of reaching a maximum and begin- 



