A. E. PALMER 
985 
entry, while 65.6 percent of 154 were shedding 
28 days later. There is no attempt to eliminate 
coccidia except when diarrhea is accompanied 
by oocyst shedding. 
Since the majority of the dogs quarantined 
are used in cardiovascular research, the elimi- 
nation of microfilaria-infected dogs is of 
major concern in the quarantine program. A 
single examination, using both direct micro- 
scopic examination and the modified Knott's^ 
test, has proven inadequate to identify all of the 
infected dogs. No attempt is made to distin- 
guish microfilaria of Dirofilaria immitis from 
Dipetalonema spp; all dogs with microfilariae 
are rejected. Results from single and multiple 
examinations for microfilaria are shown in Table 
I. Multiple examinations increase the incidence 
of microfilaria detection. Single examinations re- 
vealed microfilaria in 4.1 percent of the dogs 
while 3 examinations revealed microfilaria in 7.6 
percent of the dogs. To reduce the number of 
microfilaria positive animals received from the 
vendor, the laboratory examines dogs for micro- 
filaria while they are held in the vendor's facil- 
ity. Blood is collected, placed in the Knott's 
solution, and shipped to the laboratory for eval- 
uation. The intent of the program is to examine 
each dog at least 3 times prior to its delivery to 
NIH. Of 2,756 animals examined under this 
program, 1,757 received 2 examinations and 41 
were examined 3 times. However, the NIH has 
diagnosed microfilariasis in an additional 5.8 
percent of the 1,377 dogs delivered since the ini- 
tiation of this procedure. 
Various disease conditions exist with low in- 
cidence among quarantined random source 
Table I. — Results of Microfilaria Screening of Random 
Source Dogs 
Positive No./Percent 
Category 
Number 
tested 
Test 1 
Test 2 
Test 3 
Total 
1 Test 
2,750 
113/4.1 
113/4.1 
3 Tests (weekly) 
895 
23/2.6 
36/4.0 
9/1.0 
68/7.6 
At Vendor 
1 Test 
2.756 
212/7.7 
212/7.7 
2 Tests 
1,757 
103/5.9 
103/5.9 
3 Tests 
41 
3/6.8 
3/6.8 
After Testing 
At Vendor 
3 Tests 
1,377 
41/3.0 
17/1.3 
20/1.5 
78/5.8 
DIRECT SMEAR 
1,377 
35/2.5 
MODIFIED KNOTTS 
1.377 
41/3.0 
dogs. Those frequently seen include dermatitis 
(including parasitic, fungal, bacterial and idio- 
pathic), otitis, opthalmic problems, fight 
wounds, metabolic diseases and, rarely, neuro- 
logical diseases. These are insignificant in com- 
parison to the respiratory disease problems 
since they rarely cause mortality. 
Cat Morbidity and Mortality 
Cats are purchased unconditioned and are held 
for a 45-day quarantine period in the NIH facil- 
ities. During fiscal year 1971, 35.1 percent of 
2,510 cats became ill and 14 percent died. Fig- 
ure 4 presents the monthly rates for morbidity 
and mortality from all causes during this pe- 
riod. Morbidity was highest during the winter 
and lowest during spring and autumn months. 
Mortality rates were variable, with November 
and July being peak months. The same data are 
shown by week of quarantine in Figure 5. More 
than half of the morbidity and mortality occurs 
during the first week; 80 percent during the 
first 3 weeks. A large number of early deaths 
are caused by feline panleukopenia, while ill- 
ness and death occurring later in the quarantine 
is often caused by respiratory or enteric dis- 
ease. 
Respiratory disease is the major cause of 
morbidity among random source cats. The 
course of the disease syndrome is usually simi- 
lar in the early stages to the condition seen in 
dogs ; however, the mortality rate is lower. Sev- 
eral viruses have been identified as causes of fe- 
MORBIDITY AND MORTALITY OF RANDOM SOURCE CATS DURING QUARANTINE, 
BY MONTH - FY 1971 
60 
55 
50 
45 
40 
H35 
UJ 
O30 
lij 
0- 25 
20 
15 
10 
5 
0 
I I Morbidity 
^ Mortality 
235 
TOTAL JUL AUG SEPT OCT NOV DEC JAN FEB MAR APR MAY JUNE 
2510 282 198 287 177 180 243 218 257 199 154 190 125 
MONTH 
Figure 4. 
