XI 



THE DEPRECIATION AND THE RENEWAL 

 OF THE DAIRY HERD 



Dairying would be a much less complex and 

 exacting business if it were not for the constant 

 necessity of replacing the cows which for one 

 reason or another drop out of the herd. This shift 

 and change in the make-up of the working herd is 

 much greater than one would expect until one 

 considers the various factors involved. 



The cow is fairly long-lived, although not equal- 

 ing the horse in this respect. Many cows are still 

 useful at thirteen to fifteen years of age. The 

 records of registry associations show that an oc- 

 casional individual is still bearing young and 

 milking up to twenty or more years. The bovine 

 wonder of the world so far as age is concerned was 

 the cow Old Grannie recorded as No. 1 in the 

 Aberdeen-Angus herd-book. She is credited with 

 dropping twenty-five calves, the last one in her 

 twenty-ninth year and finally dying at the (for 

 cows) ripe old age of thirty-six. Probably if it 

 were desirable to retain cows to extreme age, many 

 would reach a quarter of a century. Nevertheless, 



107 



