112 Report of Department of Animal Industry of the 



creased with the decrease of phosphorus. The increase in the 

 calcium of the feces in the calcium-phytate period was equivalent 

 to about the amount of calcium increase in the ration. In the last 

 period, the calcium was very much in excess of the calcium in the 

 feces of the first two periods. 



INFLUENCE OF PHOSPHORUS ON THE MILK. 



The remarkable results of the work reported by Jordan, Hart and 

 Patten in which it was clearly shown that the removal of various 

 compounds from the bran influenced both milk fat and milk flow 

 were confirmed in this experiment, though not in so striking a 

 degree. The data in Table VI are graphically presented in Fig. 3 

 whose ordinates represent the percentage of fat in the milk, the 

 amount of fat in the milk and the amount of milk flow. The abscissa 

 is not used here for quantitative representation. The base line is 

 divided into parts representing the successive periods, with 

 space for the transition periods, and the amounts of phosphorus 

 given are also indicated here by numerals. Each curve has a dift'er- 

 ent scale and is placed at a convenient distance from the others 

 to facilitate comparison. The top curve (A) represents the per- 

 centage of fat in the milk and is dra^vn to a scale of one-tenth of 

 1 per ct. to .03 inch; the middle curve (B) represents the total 

 amount of fat and is dra^vn to a scale of 4 grams to .03 inch; the 

 lowest curve (C) represents the milk yield and is drawn to a scale of 

 fifty grams to .03 inch. For comparison, the results of the previous 

 experiments (by Jordan, Hart and Patten), are plotted in a similar 

 maimer (Fig. No. 4). The curves have a general tendency to decline 

 as the period of lactation progresses; this makes the high average 

 yield during the week following the end of the calcium phj^ate 

 period significant. In all cases where the phosphorus of the ration 

 increases it is immediately followed by a drop in the milk flow, and 

 the withdrawal of phosphorus is followed by a larger yield of milk. 

 Between the week of rapid rise in milk flow which followed the calcium 

 phytate period, and the prolonged low phosphorus period, there 

 is a large decline due to some unknown factor, probably lack of 

 appetite and associated disturbances, but during this low phosphorus 

 period, the milk flow was on a gradual though small increase until 

 the final break which caused the discontinuance of the experiment. 

 These changes are small — from 2 to 20 per ct. in experiments 

 I, II, and III, and from 5 to 7 per ct. in experiment IV — but the 

 results are consistent, with the exception of the last period of experi- 

 ment III, in which are probably showai the effects of protracted 

 malnutrition. The line representing the fat content of the milk 

 moves up and dowTi regularlj'- as the amount of phosphorus in the 

 ration increases and decreases. The response is in this case also 

 immediate. The change is not a mere matter of fluctuation in 



