MODIFICATIONS IN TOTAL BODY WEIGHT 



69 



4. Modifications of growth in total body weight. No change 

 occurs in the growth of castrated males, Stotsenburg ('09). 



A slight increase in growth was observed by Hatai ('03 a, 

 p. 61) after lecithin feeding. 



Increased growth occurs in spayed females, Stotsenburg ('13). 

 This increase is in part due to the accumulation of fat and in 

 part to general enlargement. 



Growth in body weight Albino Rat 



Body n>om m ar.m. 



Chart 4 Growth in body weight on age for 485 days. Males and females. Observations 

 by King (MS., '15). Data from two series combined. See table 67. 



Bearing young also causes an increase in body weight in the 

 females, J. B. Watson ('05). 



A decrease follows all forms of underfeeding (Hatai, '04 a, 

 '07 a, '08; Donaldson, '11 a) including feeding with certain vege- 

 table proteins. See many references to Osborne and Mendel in 

 chapter 4, Physiology: Nutrition, p. 61. 



Decrease also follows an excessive meat diet when begun with 

 young animals (Mus norvegicus) (C. Watson, '06, '06 a, '06 b). 



