134 DAIRY CATTLE AND MILK PRODUCTION 



index of the value of the cow is shown clearly by com- 

 paring the records of the best Holstein cow and the best Jersey 

 cow as given in Table 5 from the records of the Iowa Ex- 

 periment Station. There will be noticed that in this case the 

 per cent of fat in the milk of the best Jersey was 7 per cent, 

 while that of the Holstein was 3.81 per cent. Judging by the 

 per cent of fat alone, the Jersey would have been counted a 

 much better animal, while the total fat production for the year 

 was 5 pounds less with the 7 per cent of fat than with the com- 

 paratively low per cent of fat of the Holstein. In this case, if 

 the animals had been judged by the amount of milk produced, 

 the best Holstein would have been counted much better than 

 the best Jersey, as she produced nearly double the amount of 

 milk. 



Table 6 is compiled from the records of the University of 

 Missouri herd. The milk, per cent of fat, and total fat 

 production for a year is given for some of the best and some of 

 the poorest in each breed. 



These figures show that high fat production is not neces- 

 sarily connected with a high average per cent of fat. In fact, 

 as a rule the highest production of fat is accompanied with a 

 per cent of fat average for the breed or lower. No general 

 rule can be drawn on this point. In many cases the cows hav- 

 ing the lowest fat production in the herd have the highest fat 

 percentage, while in other cases the fat content of their milk 

 is also low. The point to be kept in mind is that cows vary 

 far more in total milk production than they do in the fat con- 

 tent. 



In the figures given, one Jersey produced over five times as 

 much milk as another, and this is not unusual with any breed. 

 It might be possible to find one cow that would show an aver- 



