Studies on the Endocrine Glands 355 



In 100 Parts. 



(1)) Husks: 



Water 

 Ash . 

 Calcium 

 Protein 

 Fat . 

 Starch 

 Cane suijar 

 O hi cose 

 liesiduc ' 



0-351 

 3-8()0 

 004S 



1.S112 

 6()8() 



4M!)21 

 4-521 

 2-982 

 8-580 



On March 25 the food was chauiied to rusks and water alone. From 

 March 25 until IMarch 31, 1 grni. of dry ox-thyroid per rat per diem was 

 added to this diet. From April 1 until April 7, O'Ol <jrm. of dry ox- 

 parathyroid per rat per diem was added, the thyroid which they had been 

 receivinc; beint; omitted. 



Some change had to be made in the number of rats in the three groups 

 in the course of the experiment. Six male rats were included, as has 

 already been stated, in A group and six in B group during the first three 

 weeks, and the same number during the first two weeks inC group. From 

 the fourth week until the eighth week there were only five rats in A group 

 and five in B group, and after a certain time the number in C group was 

 also different, since one of these animals died on the second day of the fifth 

 week and another on the seventh day of the sixth week. Further, two rats 

 of A group (the tiiyroid-fed unoperated control group) died during the tenth 

 week — one on the first day and the other on the third day. 



The animals were always weighed at the same time of day, between 

 3 and 4 p.m. The average body- weight is given in Tables I.-IIL (see 

 Appendix). After thyroid feeding there was a considerable difference in 

 weight at the beginning as compared with the end of the feeding, but 

 the full dift'erence is not shown in the tables, since these give only the 

 average weight during the week of feeding. 



After the eighth week one rat of each group was killed for histological 

 examination. During the tenth week only one rat of A group, one of 

 C group, and three of B group were available for the investigation of 

 parathyroid feeding. 



Before operation the amount of food consumed by the three groups of 

 animals showed no marked difference, and in A group (unoperated) it 

 remained the same throughout. But after the operation differences in the 

 amount consumed by B group and C group show themselves (Tables L- 

 III. and Chart 1). The amount of food consumed by B group rose 

 gradually during the period extending from the fourth to the sixth week. 

 Whether this was due to the recovery (rebound) from the diminished 

 output immediatel}^ consequent on the operation, or to the actual removal 



* Obtained after filtering off glucose converted from starch. 



