498 
Journal of Agricultural Research 
Vol. XXVI, No. 10 
adherent to the testicular coverings and could be stripped out only 
with great difficulty. The right testicle was normal. The thoracic 
organs and the liver, kidney, and intestines were normal. The spleen 
was slightly thickened and showed areas of hemorrhagic infarction. 
There was a gelatinous infiltration in the dorsal and lumbar portion of 
the spinal canal. 
COMPLEMENT FIXATION TESTS OF SERUM 
Samples of serum were drawn from this animal from time to time 
between the years 1913 and 1921 and were subjected to the complement- 
fixation test for dourine. Quantitative tests of the serum were made, 
starting with 0.2 cc. and decreasing to 0.03 cc. 
TECHNIC OF THE TEST. 
The hemolytic system consists of 1 cc. of a 3 per cent suspension of 
washed sheep corpuscles, 2% units of hemolytic amboceptor, and 1X 
units of complement, the latter being titrated each day a test is made. 
The antigen consists of a suspension of Trypanosoma eqmperdum , the 
causative agent of the disease, and is recovered from the blood of arti¬ 
ficially infected rats, as described in a previous paper, 3 Two to three 
units of antigen are used in the test, provided four times this amount 
shows no anticomplementary action. The serum is inactivated at 58° 
C. for 35 minutes in physiological salt solution. 
Table I .—Samples of blood serum of horse 128 tested at intervals during IQ13-IQ21 
Date. 
Varying quantities of serum (cubic centimeters). 
Se¬ 
rum 
con¬ 
trol 
(cu¬ 
bic 
cen- 
ti- 
me- 
ters). 
0.03 
0.04 
0.05 
0.06 
0.07 
0.08 
0.09 
O.I 
O.I 5 
0.2 
0.2 
Nov. 15,1913. 
<* SI. 
SI. 
&I+ 
1+ 
c 2 + 
2 * 4 * 
2 + 
<4+ 
4 "t” 
4+ 
Dec. 23,19x3.. 
si. 
si. 
1+ 
2*t” 
2-f- 
*3+ 
2 ~f- 
4 + 
4+ 
_ 
Mar. 6,1914. 
SI. 
SI. 
SI. 
1+ 
1+ 
3 + 
_ 
May 22, 29x4,.... 
SI. 
si. 
1+ 
J-f 
J 
1+ 
2 + 
3 + 
4 + 
4 * 4 ^ 
_ 
Aug. 13, 1914... 
SI. 
2~f* 
3 + 
4+ 
4 + 
1+ 
4 + 
4+ 
4+ 
3+ 
4 + 
it 
4 + 
4 + 
4+ 
__ 
Beb. 28,1916. 
3 + 
1+ 
3 + 
2*f~ 
3+ 
, 
Jan. it, 1917. 
_ 
_ 
SI. 
SI. 
I-f 
4+ 
_ 
Dec. 14,1917. . 
_ 
SI. 
2 + 
2 "f“ 
3 + 
SI. 
4 + 
1+ 
4 + 
1+ 
4+ 
4+ 
3 * 4 " 
_ 
Mar. 14.19x9. 
_ 
SI. 
2+ 
_ 
Mar. 19,1920. 
_ 
SI. 
si. 
SI. 
SI. 
Sl. 
1+ 
3+ 
2-f 
3+ 
3+ 
_ 
Nov. 2,1921... 
_ 
1+ 
1+ 
1+ 
2 + 
_, 
<* SI.—less than 25 per cent fixation of complement. 
& 1+—25 per cent fixation of complement. 
« 2+— so per cent fixation of complement. 
* 3+—75 per cent fixation of complement. 
* 4+—100 per cent, or complete fixation of complement. 
As will be seen from Table I, the serum of horse 128 at no time gave 
a 4 + reaction with a quantity lower than 0.06 cc., and with this amount 
only on one occasion. The serum titrations in general show a fairly 
constant result with several exceptions. Whether these exceptions 
(August 13, 1914, and December 14, 1917) are indications of a fluctu- 
* Reynolds, F. H., and Schoening, H. W. an improved method for recovering trypanosomes 
FROM THE BLOOD OF RATS FOR ANTIGEN PURPOSES IN CONNECTION WITH COMPLEMENT FIXATION. In Jour. 
Agr. Research, v. 14, p. 573-576. 1918. 
