150 Maine Agricultural Experiment Station. 1919. 



Hambie, Gertrude's Jap, Fairy Glen's Raleigh, and Fontaine's 

 Caiest are not entirely correct as the pedigrees of these bulls 

 are not complete since they run into foundation stock. 



The coefficients of inbreeding for the pedigrees of these 

 inferior bulls show that out of the 47 sires only two have re- 

 peated ancestors in the second ancestral generation. One of 

 these sires is of island breeding. The other is not. The in- 

 breeding in the two succeeding generations increases markedly. 

 The total inbreeding as measured by Z T ? ranges for the dif- 

 ferent bulls from nothing to 41.18 per cent of the total possible 

 inbreeding. The average is 9.65 per cent for the forty-seven 

 sires. This average is 2.57 higher than is the total inbreeding 

 for the superior sires. The superior sires are consequently less 

 inbred than the inferior sires. 



Of the forty-seven sires eighteen show ancestors in the 

 sire's side of the pedigree which are repeated in the dam's side 

 making the sire and dam related. The pedigrees for the supe- 

 rior sires showed 10 where the sire and dam were related. Con- 

 sidering the difference in the numbers of these two series there 

 is, proportionately, about the same number of related sires and 

 dams bred together to give either set of sires. 



The pedigree analysis for island breeding shows that there 

 are five which have no island ancestry either males or females 

 up to the fifth generation. There are six sires which have 

 island ancestry only through one side of the pedigree. As 

 already pointed out the sires of superior merit have only two 

 sires in this class (as few island ancestors). To this extent, 

 at least, the superior sires have more island blood than do the 

 inferior sires. The mean number of males of island breeding 

 occurring in the pedigrees were 6.94 and the mean number of 

 females of island breeding 6.55 for these inferior sires. The 

 figures for the sires which increased the production of their 

 daughters as previously quoted are 8.07 for the males and 7.79 

 for the females. There are consequently more island bred 

 males and more island bred females in the pedigrees of the best 

 class of sires than in the class of sires which lower the produc- 

 tion of their daughters. 



This information as to island ancestry is classified also as 

 to whether the island ancestor occurs in the sire's or dam's side 

 of the pedigree. The largest possible number of island ances- 



