14 BTJULETIN 10&7, U. S. DEPAETMEXT OF AGRICrLTURE, 



carried on with the feeding of decomposed silage taken from the 

 top of a silo when it was opened. From 5 to 15 pounds of this 

 material were fed to each cow one hour before milking. It was 

 noted that 5 pounds of this imparted a very strong flavor and odor 

 to the milk, described as " resembling garlic " by several of those 

 who passed upon it. As much as 15 pounds of this material was 

 eaten readily by the cows under experiment. Even after aeration 

 it was found that when the quantities fed were as low as 5 pounds, 

 sufficient of the objectionable flavors and odors remained to render 

 the milk objectionable to the consumer. 



DISCUSSION OF CORN-SILAGE EXPERIMENTS. 



It is apparent that under the feeding conditions in these experi- 

 ments the danger of tainting milk during production by exposure 

 to stable air containing the odor of silage is not so important as 

 some have stated. It is shown, however, that ventilation plays an 

 important part in preventing the tainting of milk during milking, 

 and, further, that milk should be removed from the stable immedi- 

 ately after it is drawn. Statements have been made, and pos- 

 sibly it has been the general belief, that the greatest source of silage 

 flavors and odors in milk is silage-tainted barn air. These experi- 

 ments show that silage flavors and odors are almost wholly taken 

 up by the milk within the body of the cow. Whether silage is fed 

 before or after milking, the bam should be carefully ventilated be- 

 fore milking is started. 



In the feeding of silage before milking, these experiments show 

 that when as little as 10 pounds to a feed was given, the milk took on 

 through the body of the cow a faint feed flavor and odor. As the 

 quantity was increased to 30 pounds at a feed, the degree of silage 

 flavor and odor was likewise increased. It is also shown that careful 

 aeration materially reduced the degree of both feed flavor and odor. 



This confirms the work of Knisely (8^) who reports that milk 

 from cows fed corn silage has a more pronounced odor than milk 

 from cows fed hay. King (7) also states: 



It was demonstrated beyond question that when silage is fed a short time 

 before milking, a sweetish odor is imparted to milk. 



An article in Hoard's Dairyman (1) states: 



If silage is fed before milking, there is likely to be a silage odor in the milk. 



Many other workers have also pointed out these truths during the 

 last 20 years. 



In the feeding of silage after milking, our results do not entirely 

 agree with some other workers. It was found that when as little as 



• The italic figures in parenthesis refer to Literature Cited at end of bulletin. 



