PART II. 

 ANIMAL PRODUCTION 



CHAPTER XXI. 

 IMPROVEMENT OF ANIMALS. 



In man's efforts to secure for his use the best types of 

 live stock or farm animals he has produced the various breeds 

 of horses, cattle, sheep, swine, and poultry. He has intelli- 

 gently selected those animals which showed a tendency to 

 produce the desired quaUties. The correct principles of 

 breeding have been applied, somewhat as an art and some- 

 times also as a science. It is important that we have animals 

 suited to a definite purpose, rather than for several or all 

 purposes. Men want horses for draft and for speed; some 

 cows for milk, others for beef; some sheep for wool, others 

 for mutton; some swine for bacon and lean meat, others for 

 lard; some hens for eggs, others for meat. 



A Breed. — A group of animals which have special charac- 

 teristics of habit, color, and form is called a breed. They have 

 a tendency to transmit such characteristics without much 

 change to their offspring. The best breed to keep is always 

 the one best suited to the desired purpose. There are so many 

 breeds that one may be chosen for each particular need. 



Laws of Breeding. — There are several laws of nature 

 which govern in a large measure the maintenance of good 

 breeds and the improvement of live stock. 



The law of heredity is one of these. It means that animals 

 inherit from their ancestors certain forms, characteristics, 

 qualities, habits, and tendencies. These may be either desir-* 

 able or undesirable and are frequently both. That ^'like 

 produces hke'^ is as true with animals as with plants. If 



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