270 EXPERIMENT STATION RECORD. [Vol.43 



pens. Throughout the original experiment the pen fed the narrow (1:4.2) 

 beef-scrap ration was superior in number and weight of eggs to that fed the 

 wide (1: 5.5) beef-scrap ration, and each of these did better than the two pens 

 fed materials derived entirely from plants. In the second year another pen 

 was added and fed a beef-scrap ration having an intermediate nutritive ratio 

 (1:4.8). This pen laid more eggs and a larger proportion of heavy eggs than 

 any other pen. 



Beginning March 1, 1918, sour milk was added to the rations of the two pens 

 hitherto receiving no proteins from an aninml source. The egg records of 

 these pens for the next 170 days nearly equaled that of the intermediate beef- 

 scrap ration and were definitely higher than the egg records of the other beef- 

 scrap pens. 



DAIRY FAEMING^DAIRYING. 



Can home grown rations supply proteins of adequate quality and quan- 

 tity for high milk production? E. B. Hakt and G. C. Humphrey {Jour. Biol. 

 Chem., 38 (1919), No. 3, pp. 515-527, figs. 5).— The authors report results of a 

 study at the Wisconsin Experiment Station of the nitrogen metabolism of milch 

 cows fed cereal grains without other protein except that derived from clover 

 hay and corn silage. In the first 4-week period the grain ration consisted of 

 ground oats alone, in the second of ground barley, in the third of ground 

 corn, and in the fourth of a mixture of the three grains. The nutritive ratio 

 was approximately 1 : 8.8, with a protein intake varying from 2.1 to 2.6 lbs. 

 per head dail.y. 



The experiments started with 3 cows. Only one of them, a Guernsey giving 

 about 22 lbs. of milk a day, maintained her milk flow and remained in nitrogen 

 equilibrium throughout the 16 weeks. The others, a small grade Jersey and 

 a second Guernsey giving respectively about 35 and 32 lbs. of milk at the begin- 

 ning, showed a marked negative nitrogen balance and declined markedly in 

 milk ])roduction until nitrogen equilibrium was reached toward the end of 

 the second period. These cows were then replaced by 2 Holsteins (giving 

 about 30 lbs. of milk) in the hope that with a larger consumption of feed 

 they could utilize the protein to maintain the milk flow. Both animals imme- 

 diately showed pronounced negative balance and shrinkage in volume of milk. 



It is thus considered impossible to furnish enough protein from the sources 

 tested to enable a high-producing cow to maintain her yield. The percentage 

 of nitrogen in the milk was not perceptibly changed during periods of negative 

 balance. 



" Undoubtedly the fact that generally in dairy practice the proteins used 

 are of low production value and that the plane of protein intake often fed 

 dairy cows is lower than it should be is partly responsible for the rapid decline 

 in milk production during the progress of lactation. Probably more cows than 

 imagined are in negative nitrogen balance during the early period of lactation 

 and under siich conditions rapidly decline in milk flow to offset the losses 

 sustained by autolyzing tissue." 



Report of Rochester milk survey by the committee on public safety of 

 the common council, C. E. North {Rochester, N. Y.: Rpt. Rochester Milk 

 Survey, Comm. Pub. Safety, Com. Council, 1919, pp. 227, figs. 5). — This survey 

 was begun in July, 1919, and continued for over five months. The report 

 covers (1) statistics of the Rochester milk supply, (2) results of a canvass 

 among householders to determine the relation of family income to the amount 

 of milk used, the consumption per child, and the ratio of expenditures for 

 milk to total expenditures for food, (3) the cost of producing milk in the 

 year ended April 30, 1919, on farms in Wyoming, Monroe, Wayne, and Living- 



