522 



COLLEGE ZOOLOGY 



A. Normal 



B. Deficient 



Vitamin A 



A. Deficient 



B. After treatment 



Vitamin Bi 



A. Normal 



B. Deficient 



Vitamin D 



Figure 381. Effects of vitamin deficiency in rats. Vitamin A: two rats from same litter; 



A, weighed 123 grams, had bright eyes and sleek fur; B, had no vitamin A, weighed 56 grams, 

 had infected eyes and rough fur. Vitamin Bi: A, rat 24 weeks old did not have enough vitamin 

 Bi; B, same rat 24 hours after receiving food rich in vitamin Bi. Vitamin D: A, normal rat; 



B, rat that did not receive vitamin D, and hence is suffering from rickets. (Courtesy of U.S. 

 Bureau of Human Nutrition and Home Economics.) 



