40 METHODS OF IMPROVEMENT 



In-and-in breeding, such as breeding sire to daughter, son to 

 mother, or brother to sister, was another step forward in methods 

 of improving sheep through breeding. Undoubtedly this practice 

 occurred long before Bakewell's time, but, as far as we know, he 

 was the first to employ it as an agency for improvement. We do 

 not know whether he deliberately resorted to in-breeding or whether 

 he took it up because he did not know where to procure animals that 

 would better serve him in accomplishing his desired ends. 



As is well known to breeders with experience, in-breeding is a 

 means by which the degree of development of characters is intensi- 

 fied and fixed. Manifestly, then, it cannot be a means for doing 

 good until there has been a careful study of matings, because it 

 intensifies and fixes the bad as well as the good in an animal, and 

 any breeder who does not possess keen judgment had better not try 

 to make use of it. 



Line Breeding. — Line breeding which involves breeding to- 

 gether animals of the same family or strain, but less closely related 

 than those used in " in-breeding," has appealed to sheep breeders 

 as being less erratic in behavior than in-breeding. It has been a 

 great agency for improvement, especially among the English flocks, • 

 and perhaps it has been depended upon more than any other method 

 in developing and fixing the type of the various breeds prominent 

 in that country. Among great Shropshire breeders in England it 

 has been the prevailing practice for a breeder to select a strain from 

 which he draws his rams year after year, and it is only now and 

 then that he uses a ram that could be considered foreign to the 

 strain adopted. Earns belonging outside of the adopted strain are 

 almost invariably used with caution, and if they do not combine and 

 recombine, " nick " well, as breeders would say, with those characters 

 already prevalent and desirable they and all their offspring are 

 immediately discarded. 



Cross Breeding. — The first step in the making of many of the 

 most prominent mutton breeds of the present time consisted in 

 crossing one breed upon another. It was the improvement secured 

 by crossing the Southdown upon the old Cannock Chase and Morfe 

 Common sheep around Shrewsbury, England, that gave impetus 

 to the formation of the Shropshire breed. When Southdown rams 

 were bred to the old Wilts and Bants ewes in South England the 

 initial step had been taken in the making of the Hampshire. Bake- 

 well's Leicesters were used on the old sheep of the Cotswold Hills 



