i905.] 



Butter Tests. 



195 



figure thus obtained represents what is known as the butter 

 ratio, and this supplies us with a convenient standard for com- 

 parison of the butter-yielding capacity of the different milks. 

 It would occupy too much space to give the whole of the 

 figures obtained in these tests, but in the following table the 

 highest, the lowest, and the average weight of milk in each 

 year and over the whole period required to produce i lb. of 

 butter are set out :— 









Pounds of Milk 



per lb, of Butter. 





Year. 



No. of 

 tests. 





Shorthorn. 





Jersey. 









Highest. 



Lowest. 



Average. 



Highest. 



Lowest. 



Average. 



1900- 1 ... 



1901- 2 ... 



1902- 3 ... 



1903- 4 ... 



1904- 5 ... 



5 

 26 

 26 

 22 



7 



297 



41*02 



39*02 



33*1 

 30*00 



22*52 



20*00 



22*53 

 20*87 

 25*26 



25*03 

 27*13 



28*39 

 28*19 

 26*95 



22 - OO 

 25*00 



23- 53 

 21*82 

 18*46 



19*75 



15- 68 



16- 33 

 16-84 

 16-16 



19-94 



18- 89 



19- 92 

 18-27 

 17-83 



For the 

 whole period 



86 



41*02 



20*00 



27*92 



25-00 



15-68 



19-09 



It will be seen that the ratios obtained vary very widely, the 

 greatest variation, however, being exhibited by the Shorthorn 

 milk, 20 lb. of the latter sufficing at one time to yield i lb. of 

 butter, while at another time no less than 41 lb. were required. 

 In the same way, something under 16 lb. of Jersey milk 

 yielded i lb. of butter in November, 1902, while in August of 

 the same year 25 lb. of milk were needed. Although some 

 very poor ratios were obtained during the hot weather, when, ice 

 or cold spring water not being available, a certain amount of 

 butter may not have been recovered, generally speaking the 

 worst ratios were obtained during the winter months when the 

 cattle were indoors and living on artificial food. All recent 

 work on the analysis of milk goes to show that the daily 

 variation in composition, even when yielded by the same cow, is 

 very marked, and it has hitherto been impossible wholly to 

 explain such variations by reference to feeding or external con 

 ditions. Such variations chiefly affect the fat contents of the 

 milk, and the figures obtained at Bickenhall bear out in a 



R 2 



