162 DAIRY CATTLE AND MILK PRODUCTION 



found to be valuable. An animal which is different from 

 others of its kind by natural variation will in some cases trans- 

 mit the new characteristic to its descendants regularly. 

 Such an individual is called a mutant, and is recognized as 

 of the greatest importance in breeding operations. Other 

 individuals may have desirable characters not common to 

 their kind, but do not transmit these characteristics. In 

 every breed animals have been found that transmitted 

 characters in a remarkable manner. Some noted herds have 

 been developed mostly from the progeny of a single animal. 

 Among dairy cattle Stoke Pogis 3d and Hengerveld DeKol 

 are good examples. 



The breeder in selecting a bull for breeding purposes wants 

 the animal that will transmit certain characters, and the 

 question is how to select such an animal. What has been 

 said explains the fact often learned by experience that in many 

 cases the dairy qualities of a remarkable cow are not in- 

 herited by her offspring. The chances that the characters will 

 be transmitted are greatly increased if found in the ancestry 

 of both parents. This makes it important to select both 

 parents carefully. 



The rule of " like produces like" is only true to a limited 

 extent; and the farther we get away from the original type, 

 the smaller the proportion of cases where it holds good. This 

 accounts for the fact often observed that the offspring of a 

 phenomenal cow may be very ordinary. However, it will 

 be found that on the average there will be more good animals 

 among the offspring of such a cow than among those from a 

 cow of moderate or low dairy capacity. We must always 

 expect to find inferior animals appearing frequently in all 

 herds. No breeder can prevent it; but no good breeder fails 



