FORTY-SECOND ANNUAL CONVENTION 35 



investigational work by the Copenhagen Station : "The changes 

 made in the character of the feeds of the cows included in the 

 experiments have had no appreciable influence on the chemical 

 composition of the milk produced." The work included com- 

 parisons of roots, grains, and oil cakes of various soils, and more 

 than two thousand cows were included in the investigation. 



The Massachusetts Station has clone a considerable amount 

 of work on the effect of food on the composition of milk. The 

 Twentieth Report of the Massachusetts Station states that neither 

 linseed, cotton seed, soy bean nor corn gluten meal had any 

 pronounced lasting effect on the composition of the milk pro- 

 duced. Linseed oil fed in considerable quantities increased the 

 fat content of the milk temporarily, the milk returning to normal 

 in four or five weeks. Cotton seed oil, soy bean oil, and corn oil 

 gave similar results. At the Illinois Station soy bean meal had a 

 greater tendency than oil meal to raise the percent of the fat in 

 milk. 



The Wisconsin station found as a result of feeding rations 

 fairly high in protein that the percent of fat in the milk pro- 

 duced averaged for three years 0.07 percent higher in butter fat 

 content than the average percent during six years when a smaller 

 amount of protein was included. At the Illinois Station a 

 group of cows fed for 18 weeks on a ration low in protein de- 

 clined 0,36 percent in the test of milk produced, while another 

 group fed a balanced ration, that is one containing more pro- 

 tein, decreased 0.13 percent in the test of the milk. There was 

 0.2 percent greater decrease in the ration low in protein. If 

 time permitted other data could be cited, but in general the 

 conclusions would be the same, namely, that a goodly amount 

 of protein in the feed has a slightly stimulating effect on pro- 

 duction. 



Having touched upon the effects of breed, stage of lacta- 

 tion, and certain concentrates on the composition of milk, let us 

 now consider the effect of pasturing. The effect of pasturing 

 on the composition of milk varies. Changing cows from winter 

 feeding to pasture usually causes a rise in the solid content 

 of the milk. This rise continues for a few weeks, after which 



