910 



EXPERIMENT STATION RECORD. 



matter in mangolds or other roots ("root-dry matter"). Two other lots. Band D, 

 received a large allowance of oil rake (I lbs.), lol B receiving in addition 3 lbs. of 

 grain, and lot I> 3 Lbs. of root-dry matter. 



The details of the system of feeding varied considerably on the different farms, as 

 regards the character or amounts of the single feeding stuffs used. The report con- 

 tains detailed information as to the feed consumed and the production of the various 

 lots in each experimental period; also chemical analyses of the feeding stuffs and the 

 milk. Some of the average data forthe 2 years are given in the following table: 



Average results of feeding grain versus roots. 



The effect of the different feeds on the chemical composition of the milk Avas not 

 marked, but small improvement in the contents of solids and fat was plainly brought 

 out by the feeding of oil cakes or grain in the place of roots. A slightly higher pro- 

 duction of milk was obtained in the case of the lots fed roots than with the grain-fed 

 lots, and 1 lb. of dry matter in mangolds was, therefore, somewhat more valuable 

 than 1 lb. of grain; the dry matter of kohl-rabi, which was fed in 2 trials, was found 

 to possess a somewhat lower feeding value than that of the mangolds fed. 



For practical purposes, however, it may be assumed that the dry matter in roots 

 has a similar feeding value as its weight of grain. This is the same result as was 

 obtained by Fjord with swine in earlier experiments at the station (E. S. R., 5, 

 p. 428; 7, p. 243). The author shows that this relation will hold good only under 

 on Unary practical farm conditions, when the rations contain a sufficient amount of 

 the different nutritive substances required for milk production and when the rela- 

 tion between these is such that the rations fed are not one sided. 



A consideration of the economy of production and feeding of roots and grain dis- 

 closes the fact that nearly three times a,s much root-dry matter as grain is grown on 

 an acre of land in average seasons, and when the expense of growing the crops is 

 considered, a gain of about $7.37 per acre is obtained if the root acreage is increased 

 from about 5 to 15 per cent of the area used for the supply of winter feed to cows; 

 and if the acreage is increased from about 15 to 25 per cent, a further gain of about 

 $4.79 per acre of this area is obtained. 



The economic limit for the extent of growing roots in Denmark under present 

 average conditions of yields and prices lies at one-third of the area utilized for sup- 

 plying winter feed to cattle. The results of the investigation clearly indicate that it 

 is advantageous to arrange the cultivation of the area which is to furnish cows with 

 winter feed in such a way that, besides the requisite amount of hay, large quantities 

 of roots may be grown, so that a considerable amount of root-dry matter will be 

 available for feeding dairy cows, even if the nutritive ratios thus reached are wider 

 than those generally considered advantageous in feeding cows. 



The results obtained in the case of the different lots showed in a decided manner 

 the superior value of oil cakes over grain and indicate that f of a pound of the more 

 nitrogenous oil cakes, cotton-seed cake, peanut cake, and sesame cake, and if of a 

 pound of the less nitrogenous oil cakes, like sunflower-seed cake, rape-seed cake, etc., 



