662 Bulletin 82. 



a deviation from the most perfect health. In cattle pulse and 

 breathing vary so widely under different conditions of the 

 environment, digestive organs, exercise, etc., that it would take 

 very much greater variations than those given in the tables to 

 give true indications of disease. 



MII.K RECORD. 



The milk record may be accepted as a more sensitive test of 

 constitutional injury than temperature, breathing or pulse. It is 

 also farther reaching than these other indications, as it involves 

 a healthy exercise of all the bodily functions, and above all those 

 of appetite, digestion, assimilation and secretion. An appreci- 

 able disturbance of the health at any one point will usually be 

 manifested in this delicate balance in a variation of quantity or 

 quality of the milk. 



Belva. Taking the milk record of Belva as given in table VI, 

 we find that the milk yield in the twenty hours following the 

 injection of the tuberculin shows no constant nor striking differ- 

 ence from that of intervening days. The highest jdeld per day 

 (42.25 lbs.) was on the fifth day succeeding the third injection 

 of tuberculin, and on each of these five days the jdeld was from 

 two to five pounds above the average. The lowest yield per day 

 (31.5 lbs.) was on the fourth day after the first injection, while 

 the preceding day's yield had been over a pound above the aver- 

 age, and the two days following the injection had been respec- 

 tively two and three pounds below. 



What is more significant is that the average yield of milk for 

 the days following the seven injections of tuberculin is practically 

 the same as the average yield for the whole 47 da\ s included in 

 the experiment. This may be stated clearly in tabular form thus : 



Average of the seven days following the injections of tubercu- 

 lin 37.257 lbs. 



Average of the forty-seven days for which the milk record is 

 given 37-247. The difference is o.oi., and is in favor of the days 

 when the system was charged with the dose of tuberculin. 



Daisy. The milk record of Daisy given in Table VII shows a 

 great difference in the yield on different days, but no constant re- 

 lation between the low daily yield and the days when the tuber- 



