588 ACUTE GENERAL INFECTIOUS DISEASES 



a flock. The postmortem examination and the micro- 

 scopic findings will be sufficient to make the distinction 

 between them. Parasites in the bowels sometimes pro- 

 duce similar symptoms, particularly Trichosoma collare, 

 but an examination of one or more of the affected birds 

 would make a clear differentiation. Chronic cases are some- 

 times mistaken for tuberculosis and arthritis urica, but the 

 autopsy and microscopic examination would at once make 

 clear the difference. Inoculations with the blood into healthy 

 birds may be made to assist in making the diagnosis . 



Prognosis. — The mortality is 80 to 95 per cent. Fre- 

 quently the entire flock will die. In some outbreaks the 

 disease runs a milder course, the virulence of the infection 

 not being high. 



Treatment. — Medical. — Treatment consists in the adminis- 

 tration of bowel antiseptics and disinfectants. The course 

 of the disease is usually too rapid for any medical treatment 

 to be of value. It is advisable to administer to the entire 

 flock a solution of iron sulphate (1 per cent.), which they 

 should be allowed to drink of freely; or a solution of tannic 

 acid (0.5 to 2 per cent.), which may be administered with 

 a medicine dropper (1.0-2.0) to each bird twice daily. Some 

 have claimed excellent results with sulphocarbolates (0.2-0.6) 

 once daily. Various other medicines have been recommended 

 but none has proved to be specific. 



Vaccines and Sera.— The treatment of sick fowls with 

 vaccines and sera has not been successful to date. 



An immune serum has been made which produces a 

 passive immunity lasting for a period of one to two weeks. 

 This is recommended as a preventive when the disease 

 makes its appearance in a flock, or when a flock of birds is 

 exposed to infection. 



Vaccines (autogenic and polyvalent) have been used. 

 The results have been unsatisfactory where the birds were 

 already infected. On the other hand, very good results 

 have been reported from the use of autogenic and polyva- 

 lent vaccines to prevent the disease in the healthy birds of 

 an infected flock. Vaccines seem to establish immunity in 

 healthy flocks, preventing the disease or reducing the 



