122 MASS. EXPERIMENT STATION BULLETIN 200. 



appear to have about equivalent feeding values for horses. In place of 

 digestible matter as a measurement of nutritive value, Kellner and also 

 Arms by, as a result of more recent investigations, have adopted the unit 

 of net energy. Wliile recognizing its superiority over digestible matter 

 as a basis for comparison, the writers feel that sufficient data are not 

 available to warrant its use in the case of oat by-products. 



D. Oat Feed for Dairy Cows. 



Experiments I, II, and III. 



In addition to the numerous analyses and digestibihty trials with the 

 several oat by-products, it was thought necessary to observe the effect 

 of oat feed upon milk production. Inasmuch as it approximated hay 

 in digestibility, it was fed in comparison with hay. Thus fed, a larger 

 amount could be given daily than if used as a component of a grain 

 mixture. 



The experiments, tliree in number, with eight, four and eleven cows, 

 respectively, were conducted by the usual reversal method. The basal 

 ration consisted of a uniform grain mixture and sufficient of a first quality 

 of cow hay to meet the needs of each animal. In each half of the experi- 

 ment a definite amount of oat feed on a dry mailer basis was substituted 

 for a Like weight of hay, amounting in case of individual cows to from 

 6 to 8 pounds daily. It was fed well moistened with water and was 

 readily eaten. The average daily ration fed will be found in Table VIII. 



