IQO 



DOMESTICATED ANIMALS AND PLANTS 



and the scrub costs something, so that the increased cost of 

 giving a calf half the advantage of pure breeding cannot be over 

 a dollar apiece in a herd of this size. Moreover, this dollar is 

 not on the calf but rather on the mature animal. ^ 



Any way it is estimated, the great fact is, that by the system 

 of grading, a single parent will give to every 07ie of the yoimg of 

 the herd half the advantage of pure breeding m the first genera- 

 tion. When, however, these half bloods reach breeding age, 

 their offspring from a pure-bred sire will be not half bloods but 

 three-quarter bloods, and their offspring will be seven eighths, 

 and so on indefinitely, according to the following table : 



Rate of Improvement by the System of Grading 



By this we see that after five generations of grading the 

 offspring have attained thirty-one thirty-seconds, or nearly 

 97 per cent, of the improvement that is possible by the use 

 of pure blood, and all by the use of a single animal only at 

 any given time. By this we see, too, that the sire alone can 

 in time accomplish practically as much improvement as sire 

 and dam could both accomplish at once, and all at an expense 

 vastly less. 



Too much cannot be said in favor of improvement by grad- 

 ing. It is safe, cheap, and sure, and, moreover, it does not dis- 

 turb the affairs of the farmer. It means only the initial cost of 

 a well-bred sire, and after that the improvement of the herd will 

 take care of itself ; whereas, with scrub parents on both sides, no 



1 Of course, if the herd is being used for dairy purposes, only half the calves 

 would be utilized, which would double the cost. 



