PRAIRIE FARMER'S POULTRY BOOK 



for the blood, after passing through it, is richer in these elements than 

 when it entered. Red corpuscles are also manufactured in the red 

 marrow of the bones. 



The muscular system. Muscles by their contraction and relaxation 

 control the motions of the body. They are composed of fibers, which 

 are striated in the case of voluntary muscles and non-striated, or smooth, 

 in all involuntary muscles except the oesophagus and heart. The peris- 

 taltic movements of the alimentary tract, the pulsation of the heart, and 

 the motions of swimming, flying and walking all depend upon this won- 

 derful system of muscles. It is estimated that there are 12,000 muscles 

 in a goose, including muscles that control the movements of the feathers. 



The excretory system. Excretion is accomplished by the lungs, in- 

 testines and kidneys. The uric acid is eliminated from the blood by 

 the kidneys in the form of urates. These are semi-sohd and are con- 

 veyed to the cloaca by the urinary tubules. The urates are excreted 

 with the droppings, and can be observed as a white layer constituting 

 about one-third of the excreta. The kidneys are located in the back in 

 the cavities of the sacral region and can be recognized as reddish, gran- 

 ular masses. They often become diseased, and their failure to function 

 results in such serious disorders as gout, rheumatism and uraemic 

 poisoning. 



Tegumentary System, or Skin. The skin is the outer covering of' 

 the body consisting of several layers of cells which serve as a protec- 

 tion to the bird. The appendages of the sjcin, such as feathers, spurs 

 and nails are modified scales. The continuation of the skin within the 

 body is known as the mucous membrane. 



A Wonderful Machine 



We have considered the wonderful machinery of the hen's 

 organism. Every system of its machinery has its special 

 organs and every organ has its special w^ork to perform. It is 

 only when all these parts work in harmony that there can be 

 a healthy and productive fowl. 



If by any accident or disease any organ is impaired or put 

 out of action it may seriously affect the working of the whole 

 factory and limit, if not totally curtail, the output of finished 

 products. The importance of understanding these structures 

 is very evident. 



A Practical Lesson 



To show how this knowledge is of practical application in 

 the care of poultry, one illustration is given. Protein is 

 recognized as a very necessary constituent of the food. This 

 nitrogenous food is acted upon by the digestive fluids and 

 changed into peptone. Why? Because peptone is soluble and 

 readily transfuses through the walls of the intestines. But 



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