76 MANUAL OF FARM ANIMALS 



animals ; hence he can move animals from one climate to another 

 without serious results. Many animals show ease of acclima- 

 tization to wide changes of climate. 



Climate has a marked effect on the external coat of the animal. 

 When farm animals are exposed to cold, damp weather, the hair 

 becomes longer and thicker than if protected. This heavy 

 coat is produced at the sacrifice of flesh. In some instances 

 the exposure produces a double coat of hair, an upper one 

 being long and wavy and an under one short, fine, and fur- 

 like. The Galloway cattle furnish a good illustration. 



The food supply is of prime importance in effecting variation 

 and improvement among farm animals. In general, full feeding 

 increases size. No other conditions influence development to 

 a greater extent than the food supply. Large -breeds are devel- 

 oped from small ones largely by increasing the food supply. 

 In addition to the increase in size, there is also an increase in the 

 constitutional vigor when the animal is well fed. Withholding 

 the food supply not only arrests development but weakens the 

 capacity for future development as well. Thus it is that ani- 

 mals passing through such periods of arrested development 

 may never attain the development which they otherwise would 

 reach. In order to secure increased development — develop- 

 ment of productive function — the animal must be supplied 

 with more food than is required for the performance of the nor- 

 mal function. Again, there is a correlation between the food 

 supply and the kind of product. The Islands of Great Britain 

 have developed more high grades of flesh-producing animals 

 than any other country, and we find nutritious pastures over 

 almost all of that country. 



The care that farm animals receive will go a long way towards 

 determining the extent of variation they are likely to undergo. 

 Farm animals that are well cared for, that is, properly housed, 

 fed, watered, groomed, exercised, and the like, cannot fail to 

 respond to such treatment. Many a man has fallen short of 



