Physical Condition of Animal 15 



unusual amount of exercise, or any one of many 

 other causes, may be sufficient to decrease the secre- 

 tion of milk one -half in any one day. The effect 

 of such disturbances is usually quickly overcome, but 

 their frequent recurrence leads to a permanent diminu- 

 tion of the secretion. The nervous organization 

 of the animal is a most important factor in deter- 

 mining the effect of these various disturbing influ- 

 ences. Many of the animals in which the powers of 

 digestion, nutrition and secretion are most highly de- 

 veloped are possessed also of a highly developed and 

 sensitive nervous system, and hence are easily affected 

 by any disturbing condition. With all such animals 

 it is of the utmost importance that every condition 

 surrounding the animal should be as regular and 

 uniform as possible. Other animals of equal capacity 

 show a remarkably quiet and phlegmatic nervous 

 temperament, and are consequently slightly or not at 

 all affected by such disturbing influences. Such an- 

 imals are of great value to the milk producer, for 

 with the utmost care and regularity there are always 

 disturbing influences beyond the control of the 

 dairyman. 



