The effect of spaying and semi‐spaying young albino rats (Mus norvegicus albinus) on the growth in body weight and body length

In connection with the study of the normal body growth of the albino rat, the attempt has been made to determine the modifications in body growth which follow the removal of the sex glands.In the male albino rat, it was found (Stotsenburg '09) that (1) the growth graph of the castrates is similar to that for the normals;(2) castrates are as susceptible as normals to the incidental influences modifying growth; (3) castrates are as susceptible as normals to the forms of disease which hinder normal growth.In a series of experiments covering a period of three years, observations on the effect on body growth caused by the removal of one or both ovaries from the female albino rat have also been made.In this study a total of 121 animals was used, those of each year constituting a separate series.The operated animals numbered 63 and the controls 58.The animals were weighed at regular intervals, and from the average weights by litters the growth graphs were plotted.When complete spaying was practised the ovaries were removed in two operations; one when the animal was between sixteen and twenty-two days of age, the other a week later.The rats were always etherized and then secured in the prone position 183