HEIFERS DURING PREGNANCY AND SUBSEQUENTLY IO3 



to hasten increase in numbers in the herd. The same 

 objections, however, apply to the rearing of progeny 

 from those heifers of immature development that apply 

 to the rearing of progeny of immature heifers for the 

 dairy. Those who buy such, therefore, should give care- 

 ful attention to the question of the age of the dams that 

 produced them at the time of reproduction. It would 

 be interesting, could it be known, how much the standard 

 of the average pure-bred has been lowered through im- 

 mature breeding from parents, both male and female. 



The lessons to be drawn are clear and may be 

 summed up as follows: (i) The aim should be to avoid 

 breeding heifers so that they will be well advanced to- 

 ward maturity before producing their first calf. But it 

 should be understood that development as used here 

 means completed physical growth and not maximum 

 performance in a particular line, as where, for instance, 

 a cow or a horse becomes capable of making their best 

 records for milk production or speed respectively. (2) 

 When heifers are bred thus early, the aim should be to 

 avoid rearing the progeny for breeding, lest the standard 

 should be lowered in performance and also in breeding. 

 (3) The aim should be to select for future production 

 to the greatest extent possible animals produced by both 

 parents when they are possessed of a maximum vigor. 



