J^EW York Agricultural Experiment Station". 93 



The nitrogen compounds of the ration were well utilized and for 

 the most part a positive nitrogen balance was maintained. The 

 animal gained 19 kilos during the experiment, half of which could 

 be accounted for by the plus balance of nitrogen. There was a 

 suggestion of a paralleUsm between the nitrogen and phosphorus 

 balances. 



The former observations as to the influence of phosphorus com- 

 pounds on the oestrum and the amount of urine voided were not 

 corroborated; neither was the laxative effect previously noted. 

 The difference in the moisture content of the feces of the several 

 periods of this experiment was very small. 



A long low-phosphorus period resulted in unfavorable symptoms. 

 The animal returned to a normal condition after a week's feeding 

 on ash-rich rations includmg alfalfa, silage and wheat bran. 



The volume of the milk fluctuated inversely with the amount of 

 phjrtin phosphorus in the rations. The increase of milk flow on 

 removal of phytin was not a mere dilution. Except for the change 

 in the amount of fat, the composition of the milk was not materially 

 altered. The responses of the fat to the fluctuations of phytin 

 phosphorus were immediate and consistent, as distinct, though not 

 quite as large, as in the previous experiments. The best milk flow, 

 both as to amount and fat content, happened to occur in the period 

 of phosphorus equiUbrium. 



INTRODUCTION. 



The work reported in this bulletin is the fourth experiment in a 

 series planned by Director Jordan in 1904, for the purpose of ascer- 

 taining the specific influence of the ash constituents of plants upon 

 animal metai3olism and especially to learn what effect these very 

 important elements may have on milk production. As biochemical 

 research progresses, we have come to realize more and more the 

 very important part which the ash constituents play in all process 

 of life. Agricultural chemists have given much attention to phos- 

 phorus, and this important substance has become familiar to farmers. 

 It was naturally, therefore, the first element to be studied in this 

 undertaking, and this substance still holds the chief interest of those 

 carrying out Director Jordan's comprehensive program. 



The first task of the investigators was to find out the nature of 

 phosphorus in the grains and forage plants usually employed in 

 feeding cattle. This work was published as bulletins 238 and 250 

 of this Station by Hart and Andrews, and Patten and Hart, respec- 

 tively.^ In these bulletins it is shown that the phosphorus of the 

 grains is very largely in the form of a soluble organic compound, 



1 Hart and Andrews, N. Y. Agr. Expt. Sta. Bull. No. 238. 

 Patten and Hart, N. Y. Agr. Expt. Sta. Bull. No. 250. 



