190(i.] PUBLIC DOCUMENT — No. 38. 113 



With \mj at $15 a ton, silage at $3.50, bran at $22, corn 

 meal at $24, cotton-seed meal at $28 and middlings at t2(y, 

 the silage ration produced milk and butter slightly cheaper 

 than did the bran ration. This difference in cost is due 

 partly to the temporary variation in the cost of the several 

 grains, and partly to the slightly more favorable effect of the 

 silage ration. 



ApproxinuUe Fertilizer Ingredients in Rations (^Cosi). 



Wheat Bran Ration. 



172.29 pounds uita-ogen, valued cat .... $30 15 



134:. 92 pounds i^otash, valued at . . . . 5 40 



68.04 pounds phosphoric acid, valued at . . 2 72 



Total, $38 27 



SRac/e Ration. 



169.99 pounds nitrogen, valued at . , . . $29 69 



119.77 pounds potash, valued at . . . . 4 79 



54.88 pounds phosphoric acid, valued at . . 2 20 



Total, $36 68 



The total rations consumed by the herd contained nearly 

 the same quantity of plant food. There was a slight excess 

 of potash and phosphoric acid in the bran ration, due to the 

 richness of the bran in these two mineral constituents. 



Co7iclusions. 



1. The silage ration produced slightly more milk and milk 

 ingredients at a trifle less cost than did the bran ration. 



2. A little less dry and digestible matter was required to 

 produce a given quantity of milk products with the former 

 ration. 



3. Two animals were temporarily out of condition while 

 receiving the silage ration. This may have been partly due 

 to the effects of the heavy concentrates and partly to other 

 causes. 



Discussion of Results. 

 1. In both experiments hay and corn silage served as the 

 roughage, while a mixture of cotton-seed meal, flour mid- 

 dlings and bran, or cotton-seed meal, flour middlings and 



