PRAIRIE FARMER'S POULTRY BOOK 



A temperature test of a number of chickens showed a 

 temperature of 101°. The average for man is 98.6°. In a 

 chicken the heart beat averages 150 per minute; in man it is 

 72 per minute. This explains why respiration is more rapid in 

 fowls than in many other animals and why they soon get out of 

 condition if kept in stuffy, ill-ventilated quarters. The average 

 respiration per minute of a number of chickens was found to 

 be 33. Human respiration averages about 16 times per minute. 

 Several diseases attack the circulatory system of fowls and 

 the blood, such as dropsy, inflammation and enlargement of the 

 heart; thrombosis; cholera; anaemia, infectious leukaemia; and 

 sleeping disease. 



The lymph is a colorless fluid of value to the blood and 

 originates in the region of the capillaries, being an exudate 

 of serum from the blood into the intercellular spaces. It is 

 collected in very small tubes (lymph capillaries) which convey 

 it to two main vessels, one on each side of the spine, thence 

 upward to the base of the neck, where it is emptied into the 

 general circulation. The lymph vessels in the intestines are 

 called lacteals on account of the whitish color of the lymph 

 fluid, known as chyle. 



The Digestive System 



The digestive sj^stem, as its name suggests, receives the 

 crude food, grinds it, and prepares it for absorption into the 

 blood and for assimilation. It is the great workshop of the 

 factory, working over the raw material for replenishing old 

 cells and for the manufacture of new. 



The organs of the digestive system are : 



1. Pharynx, or throat, which receives the food from the beak and 

 mouth and forces it into the oesophagus. 



2. CEsophagus, or gullet, an elongate tube capable of vermicular 

 muscular action by which the food is forced downward into the crop. 



3. Crop, a dilation of the oesophagus, where the food is softened 

 and held in reserve for the further processes of digestion. 



4. Proventriculus, or stomach. This is the enlarged pouch to which 

 the food passes from the crop. It is provided with glands which secrete 

 the gastric juice, a digestive fluid whose action is to change the food 

 into a condition known as- chyme. 



5. Gizzard, a receptacle of the food as it passes from the proven- 

 triculus. The gizzard is provided with a tough inner membrane and 

 powerful muscular walls which assist in grinding the food and mixing 

 it with the digestive fluid, so that before leaving it is reduced to a 



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