SYSTEMATIC IMPROVEMENT OF ANIMALS 189 



On this basis, however, the two plans would compare about 

 as follows : 



By grading, the farmer would have a crop of thirty half-blood 

 calves. By pure breeding, his cows being reduced to one third, 

 the number he could have would be but ten ; that is to say, he 

 has more " blood " and therefore more improvement in his thirty 

 half bloods than in his ten full bloods, as well as more animals 



Ik;. 29. Choice (butcher) cow, $6.40 per hundredweight 

 Mumford, in Bulletin 75, Experiment Station, University of Illinois 



to stock his farm and to afford material for selection. On the 

 sire's side the expense has been the same. 



As between grading and mixed or unimproved breeding, the 

 advantage is clearly with the former. The females are the same 

 in both cases. The cost of feed for the sire is the same, and 

 the only difference is in his original cost. A sire suitable for 

 grading purposes can be had for a hundred dollars, which would 

 be but $3.33 extra for each calf, to ctitirely pay for the bull 

 with the first crop of calves. But he will raise successive crops, 



