240 ILLINOIS STATE DAIRYMEN'S ASSOCIATION. 



Table 2. Yield of milk calculated in pounds per hour, morning antl 

 evening. 



JOCK DOLLY EVA JANET ^.^ady 



Pietertje 

 a. m. p. TO. a. m. p. na. a. m. p. m. a. m. p. m. a. m. p. m. 



May 1.10 1.09 .84 .76 .76 .80 .93 .89 1.45 1.42: 



June 71 .81 .86 .84 .61. .71 .92 .94 1.26 1.30' 



July 13 .20 .75 .83 .55 .62 .77 .85 .97 1.09> 



Of the fifteen calculations in the above table ten show that more milk 

 was secreted for each hour of the time from morning until evening, and 

 five show more milk secreted for each hour of the longer period from 

 evening till morning. The differences in favor of the longer period are 

 very slight and never ovei .04 of a pound per hour, or about 4 per cent. 

 On the other hand the excess in favor of the shorter period is commonly 

 much larger — in case of Lady Pietertje for July rising to .12 of a pound 

 or 11 per cent; and in the case of Eva for June to .1 of a pound per hour, 

 or 14 per cent. This difference in favor of greater rapidity of milk 

 secretion between the morning and evening milkings may be due either 

 to the shorter period or to the time of day. Experiments now in pro- 

 gress in which the milking periods are each 12 hours in length have thus 

 far failed to show any advantage of the day over the night for milk 

 secretions. This seems to indicate that for milking periods of unequal 

 length the yield of the shorter is greater in proportion to the time in- 

 volved than that of the longer. 



VARIATIONS IN FAT. 



Table 3. Total yield of fat in pounds per month, morning and even- 

 ing milk. 



JOCK DOLLY EVA 



^ a. m. p. m. a. m. p. m. a. m. 



May .....15.30 13.60 15.60 13.40 10.30 



June 10.60 9.90 14.71 12.23 9.24 



July 1.73 2.22 13.21 12.23 7.73 





JANET 



Lady 

 Pietertje 





p. m. 



a. m. D. m. 



a. m. p. m» 





9.93 



15.70 13.27 



18.43 17.72 



/ 



8.59 



15.15 13.06 



15.79 14.2S 





7.78 



13.17 12.43 



13.37 13.70 





