28 PRINCIPLES OF SWINE BREEDING 
as fast or faster than you go right in the other case. If it is 
true that in-breeding intensifies weakness of constitution, lack 
of vigor, or too great fineness of bone, as we all belicve, is it 
not as reasonable and as certain that you can intensify strength 
of constitution, heavy bone, or vigor, if you have those traits 
well developed in the blood of the animals you are in-breeding 
with? The latter is certainly my belief and experience... . 
I believe there is little or nothing to fear from kinship of 
animals mated if they are suited to be mated together.” 
Mr. Gentry states that he has not used a boar other than 
his own breeding for twenty years, and describes the good 
results from using the great boar Longfellow 16,335, and 
Longfellow’s sons and grandsons in his herd. One instance 
is a boar he showed at the World’s Fair in Chicago in 1895. 
This boar weighed 660 pounds at 13 months and 6 days of 
age, and possessed as much action, strength, vigor, and mas- 
culine development as any boar he ever saw. The sire of 
this boar was a son of Longfellow, the dam was a daughter of 
Longfellow, and the sire of the dam was by the sire of Long- 
fellow. This is an example of very close in-breeding producing 
remarkably good results. 
Prominent swine breeders resort to in-breeding at times. A 
very successful breeder told the writer that he did not care to 
practise very close breeding as a rule, but he would not hesitate 
to mate animals as closely related as cousins. Mr. Gentry 
states that at first he practised in-breeding through necessity, 
not being able to find boars outside his own herd which he 
thought suitable for his use. No doubt many a breeder has 
found himself in a similar position at times, and there is no 
doubt that a certain amount of in-breeding would be preferable 
to using unrelated males which were of inferior quality. 
The history of animal breeding shows that in-breeding has 
