Character in Old Breeds. 127 



culation and nutrition both dependent upon the muscular 

 tissues and their extent, according to that of the general 

 muscular structure. In some cases, disproportionate size 

 is caused in certain parts by largely increased use of the 

 muscles, and increased blood supply, according to increased 

 motion and demand. This is seen in the large hind- 

 quarters of cows that yield much milk for their size ; the 

 large supply of blood in the hind-quarter artery system, 

 and the capacity of the arteries being augmented by in- 

 creased quantities of blood to supply the increasing de- 

 mand in forming milk. In such formed cows the gradual 

 increase of blood in the hind parts leaves the fore parts 

 reduced in proportion, so giving rise to the wedge-shaped 

 form. 



This modification of form may take place to some ex- 

 tent after maturity ; but generally at mature age, which 

 varies somewhat, full growth is attained. Hence, though 

 the proportion of parts may be somewhat altered, there is 

 no general increase in growth after mature age; and as a 

 widely general rule the general muscular development in 

 cattle of any breed is according to the extent of their regu- 

 lar activity during the growing period, or until mature age 

 is reached. 



Abundance of accessible feed undoubtedly reduces the 

 extent of voluntary exercise, causing a corresponding re- 

 duction in muscular proportion to total size, in this way 

 developing the fat-forming tendency by reducing activity. 

 But in reducing muscular proportion by reducing activity, 

 thus increasing size at the expense of muscle, the circula- 

 tion, vigor, activity, and breeding capacity are all dimin- 

 ished. 



When enlargement in size takes place, with reduced ac- 

 tivity, vigor and constitutional vitality, or power to live, 

 is reduced as muscular proportion is diminished. 



