COMMON POULTRY DISEASES 311 



Roup is an infectious disease, which generally attacks the 

 mucous membrane lining the nose, and the orbit of the eye. 

 The affected parts become red, and, as the disease develops, 

 are distended, owing to the formation of pus. When the 

 disease is fully developed in the orbit, the pus pushes the 

 eye forward, and makes it bulge. Birds of poor vitality 

 are especially liable to roup in the winter and spring, damp 

 weather and poorly ventilated houses leading to its develop- 

 ment. Roup is transmitted from bird to bird largely through 

 the drinking water. The germs from the affected birds 

 drop into the water, and thus get on the body of well birds 

 that come to drink from the same vessels. The best mode 

 of prevention is to put hi the drinking water a small amount 

 of copper sulfate, potassium permanganate, or kerosene 

 to kill the germs. Birds attacked with roup should be 

 isolated, and the affected parts of the body thoroughly 

 washed with a five per cent solution of creolin or peroxide 

 of hydrogen. Roup may be cured; but it is dangerous 

 to put birds back into the laying pens before they have 

 entirely recovered. 



Canker is somewhat similar to roup in its appearance 

 and is believed to be caused by the same organisms. Yel- 

 lowish-white spots appear on the inside of the mouth and 

 throat. Close inspection shows that they are formed of a 

 hard, cheesy material. Its effect on the birds is almost wholly 

 to suspend production, and greatly to lower the vitality. 

 It is caused by keeping the birds in damp, poorly ventilated 

 quarters in which the germs rapidly multiply. Canker may 

 be treated by scraping off the white deposit, and washing 

 the parts with a 50 to 100 per cent solution of creolin or 

 hydrogen peroxide. Observation shows, however, that 

 relief is rarely permanent. When such birds are treated, 

 and put back into the laying flock, there is danger of carrying 

 the infection over from one season to another. Roup and 

 canker are usually found closely associated one with another. 



