30 DISEASES OF DOMESTICATED BIRDS 
blood stained feces and mucus. The lungs show circumscribed areas 
of congestion. On opening the cranium a profuse subdural exudate 
is observed. The meninges are injected and the ventricles contain 
an abnormal amount of discolored serum. 
Symptoms. Information regarding symptoms is limited to ob- 
servations made on the behavior of inoculated cases only. A short 
time after inoculation, birds display evidence of depression. There 
is staggering gait with effort to balance with the aid of the wings. 
If the birds are not disturbed they will lie in one place until death 
occurs in coma. Sometimes diarrhea occurs immediately before 
death. 
Pathogenesis. Fowls are susceptible to intravenous or subcu- 
taneous inoculation and by the feeding of cultures. The mortality 
is heavy among fowls when the disease is spreading under natural 
conditions. Pigeons, rabbits and mice are susceptible. Intravenous 
inoculation of the duck may cause loss of coordination and death 
with endocarditis. Sparrows are more resistant than pigeons and 
chickens but succumb to large intramuscular and intraperitoneal 
doses. In the dog, intravenous inoculation causes rise of tempera- 
ture and lameness apparently due to a transitory arthritis. Ab- 
scesses may occur in the dog, a point of interest in that suppuration 
has not been ebserved in other animals. Guinea pigs, swine and 
sheep prove refractory. Cats may succumb to intraperitoneal in- 
oculation. Horses exhibit a disturbance of health following intra- 
venous inoculation. 
Immunization. It is possible to immunize a fowl by intra- 
venous inoculation of killed culture so that the bird will tolerate 
an otherwise fatal dose of virulent culture. Successive injections 
of virulent culture cause the blood serum to take on protective prop- 
erties. Norgaard and Mohler have found this serum administered 
intravenously in a .5 c.c. dose, protective against a .1 c.c. intra- 
venous inoculation of culture. 
SLEEPING DISEASE 
Synonym. Schlafkrankheit, Schlafsucht, (German) ; maladie du 
somneil, (French). 
Characterization. The disease is a septicemic infection of 
fowls characterized by symptoms of sleepiness and caused by an 
encapsulated streptococcus. 
History. The disease was first described by Dammann and 
