Studies in Milk Secretion 137 



There -are in this list 159 bulls which have sons that meet 

 the requirements of this progeny test, and whose transmitting 

 powers are known through it. Of this number, 42 sires have 

 known transmitting qualities since the progeny test was ap- 

 plied on their daughters as well as on their sons. In this list 

 one bull, Hood Farm Stoke Pogis 9th has eleven sons whose 

 transmitting powers for milk production, butter-fat percent- 

 age and butter- fat are known. 



Certain bulls come out of this critical study of their sons' 

 transmitting power with much to their credit. Among these 

 animals might be mentioned Chief Engineer (2) with two sons 

 which raised the quantity and quality of the milk of their 

 daughters to a marked degree. Hood Farm Pogis is another 

 notable addition to the breed. Among the older bulls Stoke 

 Pogis of Prospect leads in his ability to give his sons the in- 

 heritable stuff to cause them to produce quantity and quality 

 in their daughters' milk. 



Some disappointments occur. Among these perhaps the 

 greatest are the sons of Hood Farm Torono. These bulls 

 without exception lowered the milk production of their daugh- 

 ters. The net decrease in the butter-fat is not large but still 

 it is significant. 



Another disappointment is Eminent with six sons. These 

 sons raised the' average milk production of their daughters 

 somewhat but lowered the butter-fat percentage of their milk 

 to such an extent as to result in a net decrease in the butter- 

 fat. 



The use of this table may be further exemplified by exam- 

 ining the lists of leading sires for their ability to transmit to 

 their sons the ability to raise the quantity and quality of the 

 milk of their daughters. 



The leading native bulls, together with their son's progeny 

 records, are : 



Hood Farm Pogis 9th 



Hood Farm Torono 



Spermfield Owl 



Loretta's King 



Sayda's Heir 3d 



Hector Marigold 



Irene's King Pogis 



Lady Letty's Victor (133) —1959.0 +0.352 —73.38 



(84) 



— 397.2 



+0.037 



—15.85 



(104) 



— 648.6 



—0.007 



—37.09 



(36) 



+ 659.6 



—0.030 



+35.52 



