I^EW YoEK Agricultural Experiment Station. 



99 



refusal of part of the ration may have been due to an excess over 

 her requirements and desires but was more probably due to her 

 dishke for the washed bran and rice, and in the fourth and fifth 

 periods to physiological disturbances. By the end of the fourth 

 period she left such large quantities untouched that it was deemed 

 advisable to decrease some of the rations. 



collection and tabulation of data. 



The methods of sampling and analysis were the same as those 

 given in Technical Bulletin No. 1. There were altogether 1,998 

 analyses recorded, mostly done in duplicate and a few in triplicate. 

 The greatest number of these analyses were made by M, P. Sweeney 

 and J. T, Cusick. This mass of data was tabulated, and in order 

 to facilitate interpretation of results, groups of days have been 

 averaged. These days were chosen before any study of the material 

 had been made in order to eliminate any partiality that might 

 unconsciously creep in. 



The cow was kept for eighteen days on the first ration so as to 

 become fully adjusted to it, and the figures for the six following days 

 were averaged as Period I to represent the normal status of the 

 animal. The ration planned to give phosphorus equilibrium covered 

 thirteen days, the last nine of which were divided into three groups. 

 The days of the first low-phosphorus period, also thirteen, were 

 grouped in the same manner. To this ration calcium phytate was 



Table III. — Apparent Digestibility* of Nitrogen and Phosphorus. 



* The difference between the amounts of nitrogen and phosphorus in the feces and 

 the rations consumed. 



