74 DAIRY FARMING 



cestors of the bull. It should also be observed to what 

 extent the bulls have sired high-producing cows. A well- 

 bred bull should have a large number of these records in his 

 pedigree. 



Many persons overvalue an animal that carries a small 

 fraction of the blood of one noted animal. A pedigree that 

 shows moderately good parents and grandparents is better 

 than one that has one or two unusually good ancestors and 

 the rest mediocre. A noted animal farther back than grand- 

 parents has no very great significance if the nearer relatives 

 are not good. 



It is doubtful if the conformation or appearance of the 

 bull in any way indicates his value as a sire of superior milk- 

 ing cows. On the other hand it is possible to judge from his 

 conformation to some extent as to the probable type of his 

 daughters. The only really safe plan for the owner of a 

 highly developed herd is to select a bull having daughters 

 in milk so that he may know the characteristics that the 

 bull transmits to his offspring. This, of course, can only 

 be done in a few cases but is always advisable when possible. 

 Care must be taken not to introduce disease by obtaining 

 a bull from a diseased herd. 



57. Cross-breeding. Crossing means the mixing of the 

 blood of two distinct breeds. It is a practice that is com- 

 mon among American farmers. The object sought is to 

 combine the most desirable characteristics of the two breeds. 

 The practice has nothing to recommend it. Breeds have 

 been developed and are kept pure in order that certain char- 

 acteristics may be transmitted regularly to the offspring. 

 When two distinct breeds are crossed the chain of inheritance 

 is broken and all possible combinations of the characteristics 

 of the two breeds appear. For example, a farmer having 



