New York Agricultural Experiment Station. 39 



Much stress has been laid in the past upon the necessity of 

 avoiding too wide a nutritive ratio, that is, too large a propor- 

 tion of carbohydrates, because of a depression of the digestibil- 

 ity of the ration, especially of the protein. In the case under 

 consideration there appears to be a gradual decrease in the pro- 

 portion of total organic matter digested from the first to the 

 third periods, and it is logical to conclude that this v.'as caused 

 by a widening of the nutritive ratio, because other conditions 

 remained the same. The protein is also apparently consider- 

 ably less digestible after the withdrawal of the wheat gluten. 

 This is due in part at least to the high rate of digestibility of 

 the protein in wheat gluten as compared with that in other parts 

 of the ration. Moreover, under these conditions the presence 

 of certain metabolic products would cause an apparent rather 

 than a real decrease in digestibility. The extent of the influence 

 of an increase in the proportion of carbohydrates cannot be 

 seen clearly in this instance, although the evidence in favor of 

 a depression of digestibility is as valid as that from which 

 former conclusions have been drawn. 



The foregoing figures make it plain that the several rations 

 furnished abundant and not unusual nutrition to the cows eat- 

 ing them, excepting, of course, the very small amount of fat 

 supplied to Cow 12 and the abnormal supply of fat in the ration 

 of Cow 10 for a short period. 



THE INFLUENCE OF THE OOMPOSITION OF THE RATION UPON THE 

 QUA:S'TITY AND COMPOSITION OF THE MILK AND MILX FAT. 



Before discussing the questions to which these investigations 

 have more especial reference, it is important to inquire whether 

 the quantity and character of the cow's product were in any- 

 way modified by the unusual character or variations of the 

 rations. 



This inquiry is all the more pertinent because of the prevail- 

 ing notion, not yet justified by any researches whatever, that 

 the composition of the ration determines to a large extent the 

 character and composition of the milk. 



