SECTION XI 



Diseases of the Respiratory 

 Passages 



In the fall, winter and spring, these diseases are 

 a scourge to the poultry raiser, unless strict san- 

 itation is observed. 



Obstruction of the Trachea 



This is uncommon, except as a result of gape- 

 worm infestation. Fig. 45 illustrates a case that 

 was sent to the laboratory with the statement that 

 it had "gapes." This bird would extend its 

 head high into the air, gasping for breath as one 

 whose trachea is obstructed by gapeworms ; it was 

 weak and unable to stand squarely upon its feet. 

 It was destroyed for examination. A piece of a 

 grain of corn was found in the trachea, surrounded 

 by an accumulation of mucus caused by the irrita- 

 tion its presence in the trachea caused. The for- 

 eign body and the accumulated mucus were ob- 

 structing the passage of air to the lungs ; hence, the 

 asphyxiation. 



Catarrh, Colds 



Cause. — Sudden changes in the weather, cold, 

 damp weather, roosting in draughts, and chilling 

 by getting wet in cold rains is often a factor in the 

 production of catarrh among birds. Such af- 

 fections are more or less contagious, but bad san- 

 itation plays an important part in their spread. 

 "Weak stock and poorly nourished birds are pre- 

 disposed to this contagion. 



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