Pituitary Extract and Secretion of Milk. 



85 



ounce was obtained yielding 1 1.5 per cent, of fat — the result of 

 "stripping." The injection was then made into the external 

 jugular vein as on the previous evening, the same quantity of 

 extract being used, viz., the equivalent of eight posterior lobes. 

 About three minutes after the operation was finished, and fifteen 

 minutes after the second milking, the udder was emptied a third 

 time and now 1.2 lbs. of milk was obtained with a fat content of 

 14 per cent. 



On the morning of February 17 the quantity of milk was again 

 distinctly below the normal as also the percentage of fat. 



The examination of the milk constituents other than fat has 

 not yet been completed. 



The conclusions to be drawn from the above experiments are 

 that, 



1. In the cow, the intravenous injection of pituitary extract 

 (whole gland or posterior lobe alone) leads to an immediate 

 secretion of milk very rich in fat. The effect, however, quickly 

 passes off. 



2. There is a corresponding diminution in the yield of milk at 

 the next milking period, and to some extent in the percentage of 

 fat, so that for the twenty-four hours there is practically no increase 

 either in the total quantity of milk or of fat obtained. 



We are indebted to the firm of Parke, Davis & Co. for the 

 supply of the material which we have used. 



Bibliography. 



1. Ott and Scott. Proc. Soc. Exper. Biol, and Med., Vol. 8, 1910, p. 48. 



2. Schafer and Mackenzie. Proc. Roy. Soc, Vol. 84, B, 1911, p. 16. 



3. Mackenzie. Quart. Jour. Exper. Physiol., Vol. 4, 191 1, p. 305. 



4. Hammond. Quart. Jour. Exper. Physiol., Vol. 6, 1913, p. 311. 



5. Gavin. Quart. Jour. Exper. Physiol., Vol. 6, 1913, p. 13. 



