Diseases of the Respiratory System 161 



birds. Thus in infected flocks an outbreak of roup usually 

 follows catarrh caused by exposure and this fact has led some 

 poultrymen to think that the disease may be caused directly 

 by exposure. In some flocks it appears annually with the 

 cold damp weather of late autumn and breaks out again at 

 every radical change of temperature and moisture conditions 

 throughout the winter. Vigorous and properly nourished 

 birds are better able to resist catarrh and consequently roup 

 than those that are delicate and improperly fed. 



Treatment. — The best treatment is prevention. The dis- 

 ease can be prevented by stopping all sources of infection. 

 Some things to keep in mind are : 



1. In introducing new birds always procure them from 

 uninfected flocks. 



2. Isolate all new birds and all birds that have been ex- 

 hibited at shows for two or three weeks to make sure that 

 they do not develop the disease. 



3. Exclude from uninfected house and yards poultry and 

 all other animals, including men, coming from those that are 

 infected. 



4. Do not use implements as hoes, shovels, etc., that have 

 been used on infected premises. 



5. Keep the birds in a good hygienic condition, well nour- 

 ished and in dry well ventilated houses and roomy yards. 



When the disease has been introduced into the flock careful 

 precaution may prevent its spread. 



1 . Immediately separate from the flock any bird that shows 

 symptoms of the disease. 



2. Disinfect the yards and houses with a 5 per cent solu- 

 tion of carbolic acid or better the cresol solution described 

 in chapter II. Remove the litter from the houses and dis- 

 infect freely. This disinfecting solution may also be fol- 

 lowed by whitewash. 



3. Use potassium permanganate in all drinking water. 



