Holstein-Friesians 15 1 



principally among the bulls. This may be 

 seen by comparing the average ages of their 

 dams and the average age of other dams. 

 By tabulation it was found that during the 

 years just before the investigation was made, 

 these cows came fresh at an average age of 

 4 years, 3 months, 21 days. The 1000 dams 

 in these pedigrees were 33 per cent, greater 

 age, that is, 5 years, 8 months, 18 days. The 

 dams of all of the bulls averaged 6 years, 3 

 months, 7 days, while the dams of the pa- 

 ternal grandsires (the point where there is 

 the greatest possible selection and conse- 

 quent elimination) averaged 7 years, 5 

 months, 5 days. This last average is over 70 

 per cent, above the average breeding age of 

 Holstein-Friesian cows, and is the highest 

 average found at any point in the pedigrees. 

 Certain bulls have become famous because 

 of their ability to sire daughters producing 

 a large amount of butter fat and consequently 

 able to enter the Advanced Registry. As a 

 general thing these famous sires appear with 

 great frequency in the pedigrees of the 144 



