DIURESIS AND MILK FLOW 



By H. Steenbock, 

 Assistant Chemist, Agricultural Experiment Station of the University of Wisconsin 



INTRODUCTION 



In studying the comparative efficiency of the nitrogen of alfalfa hay 

 (Medicago saliva) and corn grain (Zea mays) for milk production, data 

 were accumulated and published from this laboratory which suggested 

 that alfalfa hay when fed in large amounts often acts as a diuretic and 

 thus depresses the volume of milk flow.^ While this relation was not 

 found with all the experimental animals (cows), it was, nevertheless, 

 deemed of sufficient importance to merit the study of the influence of 

 specific diuretics on milk flow, as it was barely possible that the diuresis 

 which was produced upon the feeding of alfalfa hay was not in itself 

 responsible for the depression of mammary activity. 



In view of the importance which hitherto unknown constituents of 

 diets and rations have lately assumed, it is of the greatest interest to 

 dissect the various factors normally operative in the animal body when 

 feeding any of our ordinary rations. Dairy chemists have spent much 

 time and eff'ort in studying the various factors which influence the 

 secretion of milk and its composition. It seemed not improbable that if 

 any of the well-known diuretics were able to influence milk secretion the 

 means to vary the proportion of individual constituents might also be at 

 hand. 



EXPERIMENTS WITH DIURETICS ON GOATS 



Two goats in full milk flow were used as the experimental animals. 

 They were individually confined in metabolism cages which made possi- 

 ble the separate quantitative collection of urine and feces. They were 

 fed and milked twice a day, the milk of two consecutive milkings being 

 composited for analysis and measurement of volume. Careful measure 

 of the water consumed and urine voided was recorded. Control of the 

 ration consumed was kept only to the extent that results obtained could 

 not possibly be due to variation in food intake. Goat i, weighing 95 

 pounds, was fed daily a ration consisting of 2 pounds of oats (Avena 

 sativa), 0.5 pound of June-grass hay {Poa praiensis), 60 gm. of air-dried 

 casein, i pound of fresh sugar beets {Beta vulgaris), and 2 gm. of com- 

 mon salt (sodium chlorid). This provided sufficient energy and a suffi- 



• Hart, E. B., Humphrey, G. C, Willaman, J. J., and Lamb, A. R. The comparative efficiency for 

 milk production of the nitrogen of alfalfa hay and the com grain. PreUminary observations on the effect 

 of diuresis on milk secretion. In Jour. Biol. Chem., v. 19, no. i, p. 127-140. 1914. 



Journal of Agricultural Research, Vol. V, No. ij 



Dept. of Agriculture, Washington. D. C. Dec. 27, 1915 



bg Wis.— 2 



(561) 



