FEEDING SILAGE TO MILCH COWS 399 



was given each cow during the experiment. The following interesting 

 results were secured : 



Periods. Milk. 



On hay and grain 2-17 to 3-9 21.7 lbs. 



On hay, silage and grain 3-10 to 5-1 1 22.5 lbs. 



On hay and grain 5-12 to 5-25 19.6 lbs. 



It will be noted from the above that there was a decided increase 

 when the cows were changed from hay to hay and silage, and a no- 

 ticeable decrease when they were shifted back to the old ration of hay. 



The ultimate effect of the two feeds is shown in the following table. 

 Here Mr. Jordan groups the milk yields of the four cows in 14-day 

 periods just preceding or following a change in the roughage fed. 

 Total Yield of Milk, Four Cows, for 14 days. 



On hay 1,212 pounds 



Changed to silage and hay i>297 " 



An increase of 85 pounds or about 7 per cent. 



On silage and hay 1,200 pounds 



Changed to hay 1,098 " 



A decrease of 102 pounds is shown, or about 8 per cent. 

 It will be noted from the above that when the cows were changed 

 from hay to silage and hay there was a decided change or increase, 

 amounting to 7 per cent, and when the cows were again shifted 

 to hay from silage and hay there was a decided loss in flow of 8 

 per cent. In summing up the above results, Jordan reaches this con- 

 clusion: "In the experiment the addition of silage to the ration re- 

 sulted in a somewhat increased production of milk solids, which was 

 not caused by an increase in the digestibility of food material eaten, 

 but which must have been due either to the superior value of the 

 nutrients of the silage over those of the hay, or to the general physio- 

 logical effect of feeding a greater variety of foods. In other words 

 8.8 pounds of silage proved to be somewhat superior to 1.98 pounds 

 of hay (mostly timothy), the quantity of digestible material being 

 the same in the two cases. 



"Assuming the digestible matter of hay and silage to be of equal 

 value, pound for pound, when hay is worth $10 per ton silage of the 

 kind used in the experiment would be worth $2.25 per ton. But this 

 silage contained more water than the average. Had it been of average 

 quality, then the ton value reckoned on the above basis would be 

 $2.62. But in this case we should give the silage the credit of the 

 increased milk production, w^hich seems to have been at the rate of 

 85 pounds of milk to each ton of silage." 



