E. A. Watson 
171 
To control the inactivation, with each batch of suspected sera several 
known positive dourine sera as well as known (anticomplementary and 
non-specific) negative sera are included and all tested together in the 
final diagnostic test. 
Experiment showing the degree of inactivation of suspected serum 
necessary for specific reactions. 
Dose of serum, 0-2 c.c., unheated and heated at different degrees of 
temperature and tested with trypanosome antigen as in the diagnostic 
test. 
Normal 
healthy horses 
Unheated 
serum 
50 
Serum heated for 
54 
one half hour at degrees Centigrade 
56 58 60 62 64—65 
No. 
1 
+ + + 
+ 
+ + + + 
+ + 
+ 
- 
- 
- 
>9 
2 
+ + + 
+ 
+ + + + 
+ + 
+ 
- 
- 
- 
„ 
3 
+ + + 
+ 
+ + + + 
+ + 
+ 
- 
- 
- 
99 
4 
+ + + 
+ 
+ + + + 
+ + + 
+ + 
- 
- 
- 
99 
5 
+ + + 
+ 
+ + + 
+ 
- 
- 
- 
- 
99 
6 
+ + + 
+ 
+ + + + 
+ + 
(?) 
- 
- 
- 
99 
7 
+ + + 
+ 
+ + + + 
+ + + 
+ + 
- 
- 
- 
99 
8 
+ + + 
+ 
+ + + 
+ 
(?) 
- 
- 
- 
99 
9 
+ + + 
+ 
+ + + + 
+ + 
(?) 
- 
- 
- 
99 
10 
+ + + 
+ 
+ + 
+ 
+ + 
+ 
- - 
- 
- 
Inhibition. 
Non-specific. 
Dourine horses 
No. 1 
(1st year 
of disease) 
+ 
+ + 
+ 
+ -t -f + 
+ + + + 
+ 
+ 
+ + 
„ 2 
( 
99 
99 
) 
+ 
+ + 
+ 
+ + + + 
+ + + + 
+ 
+ 
+ + 
„ 3 
( 
99 
) 
+ 
+ + 
+ 
+ + + + 
+ + + + 
+ 
+ 
+ + 
4 
( 
99 
99 
) 
+ 
+ + 
+ 
+ 
+ + + 
+ + + + 
+ 
+ 
+ + 
„ 5 
( 
9 . 
99 
) 
+ 
+ + 
+ 
+ + + + 
+ + + + 
+ 
+ 
+ + 
„ 7 
( 
j9 
„ 
) 
+ 
+ + 
+ 
+ + + + 
+ + + + 
+ 
+ 
+ + 
„ 7 
(2nd 
99 
99 
) 
+ 
+ + 
+ 
+ + + + 
+ + + + 
+ 
+ 
+ + 
„ 8 
(3rd 
99 
99 
) 
+ 
+ + 
+ 
+ + + + 
+ + + + 
+ 
+ 
+ + 
„ 9 
(4th 
99 
99 
) 
+ 
+ + 
+ 
+ + + + 
+ + + + 
+ 
+ 
+ + 
„ 10 
(5 th 
99 
99 
) 
+ 
+ + 
+ 
+ + + + 
+ + + + 
+ 
+ 
+ + 
Specific complement-fixation. 
Normal mule 
1 
+ + + + 
+ + + + 
+ + + + 
+ + + 
+ 
- 
- 
- 
99 
2 
+ + + + 
+ + + + 
+ + + + 
+ + + + 
+ + 
+ 
- 
- 
Normal donkey 1 
+ + + + 
+ + + + 
+ + + + 
+ + + 
+ + 
+ 
- 
- 
99 
2 
+ + + + 
+ + + + 
+ + + + 
+ + 
+ 
- 
- 
- 
Inhibition. Non-specific. 
+ + + + See page 173 for the meaning of these reaction expressions. 
Note. In the non-specific inhibition reactions the red cells are 
loosely sedimented. In the specific complement fixation reactions the 
red cells are precipitated in a mass or agglutinated in clumps. When 
