Studies in Milk Secretion 161 



The leading sire in this butter-fat percentage performance 

 test was Clear Brook Chief 74685 raising his daughter on the 

 average 1.338 per cent of butter-fat. This sire had two daugh- 

 ter-dam pairs. The dams were both in the lowest group for 

 butter-fat percentage (class D) and this sire raised his daugh- 

 ter from these dams to the highest group (Class A). 



Among the sires with a fair number of daughter-dam 

 pairs which raised the butter-fat percentage to a marked degree 

 might be mentioned Irene's King Pogis 73182; Merry Maiden's 

 Grandson 71003; Pogis 75th of Hood Farm 94501; Jacoba's 

 Emanon 84177; and Golden Fern's Son 78687. 



Hood Farm Pogis 9th leads in number of daughter-dam 

 pairs with 42. This bull raised the butter-fat percentage of his 

 daughter on the average of 0.243 per cent over the butter-fat 

 percentage of the dams of their daughters. 



The sires mentioned as superior in the milk transmitting 

 ability, Hood Farm Torono and Spermfield Owl, do not check 

 up so well in their ability to transmit high butter-fat percent- 

 age. Hood Farm Torono caused his daughter on the average 

 to be 0.225 per cent of butter-fat below what the dams of these 

 daughters produced. Spermfield Owl only raised his daughters 

 on the average 0.027 per cent of butter-fat over what the dams 

 of these daughters produced. 



There are 224 sires of known transmitting ability for net 

 butter-fat given in table 6. Of this number only 99 sires raise 

 the butter-fat production of their daughters over that of their 

 dams. The sires which raised the production of their daughters' 

 butter-fat most were Sans Aloi 81012, Signal's Successor 72758, 

 and Golden Glow's Chief 61460. The sires which made the 

 deepest impress on the breed by raising the butter-fat of the 

 largest number of daughters over that of their dams was Hood 

 Farm Torono with 34 pairs and an average increase for each 

 daughter of 121. 51 pounds of butter-fat. The next bull, Sperm- 

 field Owl, with 26 pairs raised the butter-fat production 97.71 

 pounds on the average for each of his daughters. Some of the 

 bulls lowering the production of their daughters markly were 

 Gertie's Son of Washington 83799, Hood Farm S. Tormentor 

 9631 1, and Oxford Lad's Owl 75599. 



The information summarized above was arranged in table 

 7 to reveal the transmitting qualities for milk production, but- 



