LUNG PLAGUE OF CATTLE 375 



slow; little fever. On necropsy the presence of Aspergillus 

 fumigatus in the bronchi and consolidated lung tissue is 

 conclusive. 



(d) Verminous Bronchitis. — Affects mainly calves. Cough- 

 ing prominent. Parasites or eggs occur in the ejections. 



Course. — The course of the disease is varied. Many cases 

 recover during the early stage and after only a few days' ill- 

 ness. In others recovery is slow and often imperfect, pul- 

 monary sequestra remaining. Such an animal, as noted, is a 

 dangerous source of infection. 



The course is generally more stormy in young, well-nour- 

 ished patients, although calves are quite resistant. The 

 mortality is usually from 60 to 70 per cent. Not over 20 to 

 30 per cent, fully recover. A number remain chronically 

 affected, but may fatten. 



Depending on circumstances, the disease may persist on a 

 given premises for years. This is particularly true where 

 only those showing clinical symptoms are disposed of, no 

 thorough disinfection practised and later new cattle brought 

 in to replenish the herd. 



Treatment. — Palliative measures are rarely successful and 

 generally lead to the further spread of the disease. To wipe 

 out lung plague all sick and exposed animals should be slaugh- 

 tered and the premises they occupied (barns, sheds, etc.) 

 thoroughly disinfected. Once this drastic method is enforced 

 the disease is soon entirely eradicated. In the Uniteed States 

 and in other countries where it no longer exists, no cattle 

 should be imported from an infected country without passing 

 through a strict (ninety-day) quarantine. 



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