ILLINOIS DAIRYMEN'S ASSOCIATION. 33 



Herds in Which No Effort Has Been Made at Improvement. 



Value 

 Milk B. Fat B. Fat @ 



Milk. B. Fat. Per Day. Per Wk. 25c lb. 



Herd G 2802.4 105. G 14.8 3.94 .98 



HerdS 3439.8 129.0 18.2 4.78 1.19 



Herd U 2289.6 103.4 12.1 3.83 .95 



In this table the average production per cow for 27 weeks 

 is given together with the value of the average butter fat per 

 week at 25 cents per pound. The cows in the herd here indicated 

 were being tested simultaneously. The practice in most of the 

 herds is t< i all< >w the cows to freshen from late winter to late spring- 

 so that the stage of lactation of the cows in one herd is fairly 

 o >mparable with the others. In considering the table the first 

 thing we notice is the immense difference in the average produc- 

 tion of milk and butter fat for the different herds. In Herd F 

 the average production is 5404 pounds of milk containing 100 

 pounds of butter fat, while in Herd U the average production 

 of milk was 2289 pounds containing 103 pounds of butter fat. 

 Between these extremes we have all gradations showing the 

 great difference in productive ability. In the column at the 

 right we see that the average butter fat per week in herd F was 

 worth more than twice as much as that in herd U. Looking at 

 the table from another point of view you will see that the herds 

 have been grouped with reference to the effort that lias been 

 made in improving them. The upper group shows herds from 

 which the owners have culled out their poor cows in various ways 

 and replaced them with better ones from time to time. In some 

 a pure bred sire has been introduced. In the lower group are 

 placed three herds in which there has been no effort at ameliora- 

 tion and their production reflects very well their condition. In 

 general the sire used in the herds of this group is closely related 

 to all the cows in the neighborhood and no female is disposed of 

 until long past her days of usefulness, if she ever had any. In 

 herd F a pure-bred sire has been kept for several years, a rigid 

 selection being made among the females, resulting in a uniform 

 nerd of high average production. The contrast between these 



