SECTION LI. IMPROVEMENT OF LIVE-STOCK 



THE principal animals that add to farmers' profits are 

 horses, mules, cattle, sheep, and swine. All of these ani- 

 mals have been greatly changed by man in order that 

 they may better serve his uses. The active, slender, long- 

 legged wild hog has been changed into the round-bodied, 

 short-legged Berkshire or Poland-China. The angular, 

 long-horned wild cattle of earlier days have been trans- 

 formed into immense masses of flesh. 



The changes that have occurred in domestic animals 

 have been brought about chiefly by selection of the ones 

 best suited to their owner's main purpose. Improvement 

 in the kind and amount of food has also helped to make 

 these changes. 



Improving common or scrub live-stock. A breed is a 

 large group of animals that resemble each other and 

 whose offspring inherit the same qualities. A pure-bred 

 animal is one both of whose parents belong to the 

 same breed. Scrubs or natives are animals having no 

 ancestors that belonged to any distinct breed. Grades 

 are animals descended from both pure-bred and scrub 

 ancestors. 



Fortunately for the farmer, the pure-bred parent has 

 more influence than the scrub parent in determining the 

 form, color, and useful qualities of the grade offspring, 



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