SCIENTIFIC PROCEEDINGS 



Abstracts of Communications. 



One hundred fifth meeting. 



College of the City of New York, New York City, February 18, 

 1920, Vice-President Wallace in the chair . 



5i (1511) 



Pituitary feeding and egg production in the domestic fowl. 



By Sutherland Simpson. 



[From the Physiological Laboratory, Medical College, Cornell 

 University, Ithaca, N. Y.] 



Clark 1 found, in 191 5, that the egg production of chickens 

 (White Leghorns) was markedly increased by feeding dried pitui- 

 tary (anterior lobe) in amounts representing 20 mg. of the fresh 

 gland to each hen per day. The effect became evident four days 

 after the feeding began and lasted for several days after the last 

 dosage. The experiments were carried out in May, when the 

 laying curve was on the decline, nevertheless the egg production 

 reached 100 per cent, for the experimental pen (35 hens on two 

 consecutive days laid 35 eggs) or double what it had been before 

 the feeding was begun. He lays emphasis on the fact that the 

 glandular material he used was taken from young, growing ani- 

 mals — calves and lambs. 



I have repeated the experiments of Clark when the egg produc- 

 tion was low and declining — in June and July, 191 7, when low 

 and increasing — December and January, 1917-18, when high 

 (about the maximum) — April, 191 8 — and again in March and 

 April, 1 919, and have been unable to observe any increase from 

 pituitary feeding. The adult gland (ox) was used and also that of 

 the growing animal (calf) , and the method of preparation adopted 



1 Clark, L. N., Jour. Biol, Chept-, 1915, 22, 485-491. 



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