104 SWINE 



indefinitely. This is quite evident from observation of 

 pigs of the same litter, some of which may be entirely 

 different in general form, quality, etc., from the rest of the 

 litter. This being true, it is clearly evident that inbreed- 

 ing, — as for instance, when brother and sister, because 

 they happen to belong to the same litter, are mated, is 

 not necessarily inbreeding in the strictest sense of the 

 term because the pair may not be closely related in re- 

 spect to all the characters. Granting that inbreeding, 

 because of mating individuals whose characters are re- 

 lated, results in the production of inferior offspring, 

 such matings may still produce outstanding individu- 

 als, while at other times, which would happen more often, 

 they would produce very poor results. However, it has 

 not as yet been demonstrated that the mating of indi- 

 vrduals all of whose characters are closely related neces- 

 sarily produces inferior offspring. Such being the facts, 

 it is quite clear that proper breeding consists primarily in 

 the mating of good individuals. In general the best in- 

 dividuals of the breed should be used for breeding pur- 

 poses, and the more closely they are related the better 

 they should be selected because the more likely they are 

 to combine and transmit their characteristics to the off- 

 spring. If a sire and dam both have weak points in com- 

 mon, these will be combined and transmitted to the off- 

 spring. If they have strong points in common, they will 

 be transmitted likewise. 



GRADING. 



The method of grading as a form of breeding consists 

 in mating animals one of which is pure bred and the other 

 a scrub, grade, or cross bred animal. The sire usually 

 is the pure bred. The dam may be of any breeding other 

 than pure bred. Thus if a man starts with a herd of scrub 



