io8 PRACTICAL RABBIT KEEPING 



"In-breeding is the mating of close related 

 ones of the same species. 



"With regard to this latter form of breeding 

 the United States Bureau of Animal In- 

 dustry has bred brother and sister mated in 

 sequence order down to the loth generation, 

 cavies being the example, and regarding 

 which Dr. Schroeder writes, 'We have found 

 nothing to indicate that the intensest form of 

 in-breeding, carried on for nine or ten gene- 

 rations, is injurious. That for the preserva- 

 tion and perpetuation of especially fine points, 

 and for the establishment of new breeds 

 through the selection of naturally occurring 

 mutations we are practically forced to resort 

 to in-breeding.' 



"One factor stands out pre-eminently above 

 aM others in its relation to breeding, no matter 

 along what line the latter is practiced — that of 

 health, and the possibilities from heredity. 

 One should never mate specimens containing 

 physical defects, not when affected with dis- 

 ease whose transmission is known to influence 

 the offspring. I am not alluding to physical 

 faults, not to diseases that are curable by 

 proper treatment. These will not transmit 



