684 
Journal o f Agricultural Research 
Vol. XXX, No. 7 
sites, the differentiation being based 
partly on the presence or absence of an 
eosinophilia. This method proved suf¬ 
ficiently satisfactory until a group of 
eight colts, 2 to 4 years of age, was en¬ 
countered. These colts had been in 
and near places where infectious equine 
anemia was known to be present. 
Physical examination showed the usual 
symptoms of this disease, which are 
similar to strongylosis, some of the 
animals running a temperature of 105° 
F. or more. The high temperature 
and the absence of an eosinophilia 
pointed very strongly to infectious 
equine anemia. The disease was diag¬ 
nosed as such, and since the animal had 
been ailing for some time, was con¬ 
sidered of the chronic type. 
The animals were brought to the 
laboratory for further study and treat¬ 
ment. Repeated blood examinations 
over a period of weeks demonstrated 
the usual number of eosinophiles and 
there was no appreciable lymphocytosis, 
the differential count being well within 
the usual boundaries for normal ani¬ 
mals. A pronounced anemia was 
noted in some of the colts, the red cells 
being as low as 3,888,000 per c. mm. 
Eventually, all the animals died or 
were killed when death was imminent. 
With one exception, all showed extreme 
infestations with Strongylus and Cyli- 
costomata; this one exception having 
1,000 Gastrophillus in the pylorus. 
Repeated blood inoculations on many 
susceptible animals failed to reproduce 
the disease and for this reason infectious 
equine anemia can positively be ex¬ 
cluded. In this connection it might be 
said that in one horse which consist¬ 
ently showed from 15 to 17 per cent of 
eosinophiles, but few parasites of any 
kind were present at autopsy. It can 
safely be stated that the presence or 
absence of an eosinophilia is of little 
or no aid in making a diagnosis of infec¬ 
tious equine anemia, the only positive 
diagnosis possible at present being that 
secured by reproduction of the disease 
in an animal by inoculation. 
For the inoculation great care was 
taken to use only healthy animals and 
to see that there was no chance of 
accidental infection. 
No. 2965.—On September 18, black 
gelding 12 years of age, in good flesh 
and spirits, weighting 1,185 lbs., was 
given intravenously 480 c. c. of whole 
blood from No. 2597, a chronic experi¬ 
mental case produced by Berkefeld- 
filtered blood from a typical field case; 
September 25, given intravenously 
150 c. c. of whole blood from No. 2597; 
October 9, given intravenously 200 
c. c. of whole blood from 2597; No¬ 
vember 1, weight, 1,055 lbs.; Novem¬ 
ber 7, weight 990 lbs.; edema of 
abdomen; very weak but appetite very 
good; November 13, unable to stand; 
continued loss of weight; November 14, 
animal died. During the illness this 
animal showed the typical symptoms 
of infectious equine anemia. Blood 
examination on November 1 showed a 
slight decrease in red cells as compared 
with a count made on 
the day of the first 
inoculation. Figure 1 
gives the temperature 
record of this animal. 
No. 2563.—On 
October 22, middle- 
aged gelding in good 
physical condition 
weighing 940 lbs., was 
given subcutaneously 
100 c. c. of defibrinated 
blood from No. 2250, 
a typical acute field 
case. The first symp¬ 
toms of the disease 
were shown on Novem¬ 
ber 5. The animal 
gradually lost weight, 
became weak, the mucous membranes 
of the eyes and the nose took on a 
yellowish-red tinge and on November 
13 its weight was 840 lbs. On Novem¬ 
ber 14 there was some hemorrhage 
from the right nostril. On November 
15 the animal was unable to get^ up, 
there was some edema of the legs, and 
hemorrhage beneath the nasal mucosa. 
The animal died November 17. There 
had been a gradual fall in the number 
of red cells and in the percentage of 
hemoglobin (fig. 2). 
Fig. 1 .—Temperature record of animal No. 2965 
