98 ILLINOIS STATE DAIRYMEN'S ASSOCIATION 



Another bull was mated with cows having an average 

 yearly butterfat production of 254 pounds. His six daugh- 

 ters averaged 38 per cent more butterfat than that quantity. 

 Another sire was mated with dams having an average year- 

 ly butterfat production of 256 pounds. His five daughters 

 produced 37 per cent more butterfat than their dams. 



Not every bull-association sire increases the production 

 of his daughters over that of their dams. Records are now 

 available for 12 bull-association bulls, each having five or 

 more daughters. Among these 12 there are 9 whose daugh- 

 ters produced more milk and butterfat than their dams and 

 3 whose daughters produced less. It is interesting to com- 

 pare two of these sires. One was mated with cows having 

 an average yearly milk production of 7,419 pounds, yet his 

 daughters on an average excelled their dams by 1,645 

 pounds. The other bull was mated with cows having an 

 average yearly milk production of 7,306 pounds, and his 

 daughters produced on an average 1,038 pounds less than 

 their dams. In each case the average milk production of 

 the dams was about equal, but there was a big difference 

 in the average production of the daughters. Certainly there 

 is a great difference even in purebred bulls, and the pro- 

 duction records of the dams and daughters show how great 

 that difference is. 



The Daughters of a Hundred Sires 



Cow-testing-association figures have furnished the 

 yearly production records of many pairs of dams and 

 daughters. From these figures a hundred dairy sires have 

 been proved as far as five or more pairs of dam and daugh- 

 ter records will prove a sire. Included among these proved- 

 sire records are the records of the daughters of the 12 bull- 

 association bulls already mentioned. In every case the 

 yearly record of the dam has been compared with that of 

 the daughter after all records of immature cows were 

 figured to maturity. Altogether there were 641 daughters 

 whose records were compared with those of their dams. 



On an average the dams produced 8,084 pounds of 



