THE DIAGNOSIS OF DOURINE BY COMPLEMENT 
FIXATION 
By John R. Moheer, Adoeph Eichhorn, and John M. Buck, 
Pathological Division , Bureau of Animal Industry 
INTRODUCTION 
Dourine is a specific infectious disease affecting under natural condi¬ 
tions only the horse and the ass, transmitted from animal to animal 
by the act of copulation, and due to a single-celled animal parasite or 
protozoan, the Trypanosoma equiperdum . It is characterized by an 
irregular incubation period, the confinement of the first symptoms to 
the genital tract, the chronic course which it runs, and by finally pro¬ 
ducing complete paralysis of the posterior extremities, with a fatal 
termination, as a rule, in from six months to two years. 
HISTORY OF DOURINE IN THE UNITED STATES 
In the United States the disease was first suspected in 1885 and 
recognized in 1886 by Dr. W. L. Williams, who was then a veterinary 
practitioner at Bloomington, Ill. Officials of the State of Illinois took 
hold of the outbreak, and as a result of rigid prophylactic measures the 
disease was eradicated from the State in 1888, but not before an affected 
stallion had been shipped to Gordon, Nebr., thereby starting up a new 
center of infection in that locality. 
In 1892 dourine was again brought into public notice by an outbreak 
among the breeding horses of northwestern Nebraska, the history of 
which suggested that it originated with this Gordon stallion. After an 
expenditure of about $5,500 by the Bureau of Animal Industry the 
disease was considered to have been eradicated from that section of 
the country. Five years later the infection again made its appearance 
in the same part of Nebraska, and early in 1899 the Bureau again began 
the work of eradication. Many inspections were made, and those 
animals which were found diseased were purchased and killed. Many 
obstacles were encountered, and the disease evidently kept smoldering 
during 1900. 
In 1901 the infection reappeared with increased vigor, this time in 
the Pine Ridge and Rosebud Indian Reservations in South Dakota, in 
addition to northern Nebraska, and more stringent measures were 
immediately inaugurated to control the spread of the disease. However, 
eradication in this region was extremely difficult, owing to the wildness 
Journal of Agricultural Research, 
Dept, of Agriculture, Washington, D. C. 
( 99 ) 
Vol. I, No. 2 
Nov. 10, 1913 
A—a 
