208 Cattle Frollems. 



in nine months; while in cases of doubling the yield in 

 eight or ten weeks, as is well known to be done in some 

 cases, the danger of relaxing the udder-supply arteries is 

 increased by hundreds per cent over what it would be if 

 sixteen to twenty months were occupied in doubling the 

 yield. 



The reason of the greater danger from over-rapid thin- 

 ning of the artery walls, is the reduced and too short 

 length of time for repair, as the rate of renewal by repair 

 in the artery walls is a gradual process, which cannot be 

 hastened, like increase of milk yield. The more rapid 

 the increase of yield, the greater the clanger of engorge- 

 ment and relaxation, and the longer the period required 

 for artery rest, and renewal of the relaxed and weakened 

 walls or tissues. But the time for repair of the relaxed 

 artery walls, by assimilation, is actually reduced and 

 shortened according to the degree of rapidity at which 

 yield becomes excessive, the artery walls being excessively 

 thinned by increased engorgement, and correspondingly 

 relaxed. Hence the danger and liability to relaxation 

 and the tendency to abortion are increased according to 

 the degree of rapidity at which feed, and artery blood, 

 and yield, are increased. 



The yield of the cows of Holland was slo^vly increased, 

 their great (Sapacity being only gradually developed 

 and established, as any one knowing the necessarily scant 

 resources of the early Netherland settlers, who developed 

 the capacity of Netherland cows — and the careful habits of 

 the German people, must admit. 



The "new," or "stranger," cow class, \N'hich makes 

 up a majority of the cows in nearly all new cheese-factory 

 districts, thougli yielding only moderately, are, by far, 

 more liable to abort from artery relaxation than cows that 

 are raised on dairy farms, and have been subject to full 

 feeding from the first. The dairy farm cows are usually 



