LABORATORY OBSERVATIONS ON THE INSUSCEPTIBILITY OF RACCOONS TO Dirofilaria immitis Author(s): BRUCE M. CHRISTENSENMARY E. SHELTON Source: Journal of Wildlife Diseases, 14(1):22-23. Published By: Wildlife Disease Association DOI: http://dx.doi.org/10.7589/0090-3558-14.1.22 URL: http://www.bioone.org/doi/full/10.7589/0090-3558-14.1.22
BioOne (www.bioone.org) is a nonprofit, online aggregation of core research in the biological, ecological, and environmental sciences. BioOne provides a sustainable online platform for over 170 journals and books published by nonprofit societies, associations, museums, institutions, and presses. Your use of this PDF, the BioOne Web site, and all posted and associated content indicates your acceptance of BioOne’s Terms of Use, available at www.bioone.org/page/terms_of_use. Usage of BioOne content is strictly limited to personal, educational, and non-commercial use. Commercial inquiries or rights and permissions requests should be directed to the individual publisher as copyright holder.
BioOne sees sustainable scholarly publishing as an inherently collaborative enterprise connecting authors, nonprofit publishers, academic institutions, research libraries, and research funders in the common goal of maximizing access to critical research.
22
Journal
LABORATORY
OBSERVATIONS TO
BRUCE
Department
MARY Ames,
M. CHRISTENSEN,
E. SHELTON, Department Iowa 50011. USA
ON THE
Diro fl/aria
OF RACCOONS
of Wildlife
Diseases
Vol.
14, January,
1978
INSUSCEPTIBILITY
immitis
of Entomology
of Veterinary
Anatomy,
Pharmacology,
and
Physiology,
Iowa
State
University,
Abstract: Two raccoons, Procyon lotor, were exposed to Dirofilania immitis by subcutaneous injection of infective third stage larvae obtained from experimentally-infected Aedes fnivittafus. Nematodes were not recovered from either raccoon when examined at necropsy 223 and 254 days postexposure. Large numbers of adult D. immitis were found in six dogs used as controls. These data indicate that raccoons cannot support the development of D. immitis.
INTRODUCTION
This
Dirofilania immif is has been recovered from the domestic dog (Canis familianis), timber wolf (C. lupus), coyote (C. latnans), red fox (Vulpes fulva), domestic cat (Felis domesfica), muskrat (Ondatra zibethicus), sea lion (Zalophus californianus), orangutan (Pongo pygmaeus), black bear (Ursus amenicanus), beaver (Castor canadensis), wolverine (Gulo luscus), domestic horse (Equus caballus) and man (Homo sapiens). These reports in hosts other than dogs are, almost exclusively, natural infections; the only exception has been the experimental infec-
tion
of domestic
cats.2
natural transmission uncertain, but the rant hosts in which not become sexually
Their
role
in the
of D. immitis is majority are aberthis parasite does mature.
Procyon lotor has never been recorded as a host for D. immif is, but its ability to support a related filarioid nematode, D. fenuis, and its close association with the
Canidae
of the
it might function dog heartworm. near urban areas, large concentrations
Di Journal Paper No. 1955.
Carnivora
suggest
that
as a reservoir host for Raccoons also live in close proximity to of domestic dogs.
No. J-8930
of the Iowa Agriculture
certainly
justifies
to determine function immitis.
the as
MATERIALS
an
ability
definitive
AND
experiment
of raccoons hosts
to
for
D.
METHODS
Two laboratory-reared female raccoons, each two years old, were used in the experiment. They had been previously exposed to infection with a strigeoid trematode (Fibnicola crafena) on
several occasions. They were never exposed to, nor detected as having any other helminth infection. Six mongrel dogs, whelped during the winter and maintained in mosquito-proof mammal rooms, were used as controls. Aedes tniviffatus were maintained as previously described’ and served as the source for D. immif is. Mosquitoes had
become infected by feeding on an infected dog. At 16 days postexposure mosquitoes were dissected in Hank’s balanced salt solution and infective third stage D. immitis recovered from the head and labium were injected subcutaneously
gion with
and Home
into
the
inguinal
re-
of both the dogs and the raccoons a tuberculin syringe and 20-guage Economics
Experiment
Station,
Ames,
iowa.
Project
Journal
of Wildlife
needle. rinsed curate immitis
Diseases
Vol. 14, January,
1978
The syringe and needle several times to insure count of the number injected.
23
were an acof D.
5 months postexposure, 1-ml blood samples were drawn approximately every 14 days and examined by a modified Knott’s technique. Animals were examined at necropsy 213 to 291 days postexposure. AND
their
branches
amined surface the
were
for nematodes of the lungs
lungs
were
and
and lesions. was examined
palpated.
on gross
incisions lobe,
the
to
all
made
exparenrecovered
pulmonary were not
were any lesions
employed
of animals
control
were facilitate
carevi-
examination.
method
posure
animals
the exbecause
for
was
reliable became
infected,
and the recovered juveniles Thirty-six
number of adult D. immitis in relation to the number of injected was quite high. to 40 infective third stage D. immitis were injected into each of six dogs and from 9 to 25 adult D. immitis were recovered from each animal when examined at 213 to 291 days postexposure. Raccoons C and B were exposed to 43 and 46 infective third stage D. immitis, respectively.
and examined arteries and opened
of
The
DISCUSSION
removed All major
amination
dent
Both raccoons were consistently negative for n’iicrofilariae; therefore, raccoon G was examined at 223 days, and raccoon B at 254 days postexposure. The heart, lungs, and entire length of the postcava within the
thorax were thoroughly.
each
chyma. D. immitis from either animal, nor diovascular or pulmonary
Beginning
RESULTS
transverse through
ex-
The and
These raccoons
Numerous
data strongly cannot function
suggest that as hosts for
D. immitis.
Acknowledgements
We thank NIATD
Tom provided
LITERATURE 1.
Cook
for
by
supplying
the
the
U.S.-Japan
raccoons.
The
Cooperative
infected
Medical
used
dog Science
in this
Program-
CITED
CHRISTENSEN,
B. M.
transmission
1977.
of Dinofilania
Laboratory studies on the development and by Aedes tnivittatus. Mosq. News 37:367-
immitis
372. 2.
DONAHOE,
J. M. R. J. Parasit. KLEIN, J. B. and E. D. horse. J. Am. vet.
1975. Experimental 61: 599-605.
immitis.
3. 4.
FOIL,
L. and
beaver, 5.
WILLIAMS, Parasit.
T. Castor
C.
ORIHEL.
canadensis.
J. F. and 62:
STODDARD. med. Ass.
171:
1975.
J. Parasit.
A. W. DADE.
infection
of cats
1977. Dinofilania 354-355. Dinofilania
immitis
for publication
Dirofilania
recovered
(Leidy,
1856)
from
a
in the
61: 433. 1976.
Dinofilania
immitis
174-175.
Received
immitis
with
29 August
1977
in a wolverine.
J.
BioOne (www.bioone.org) is a nonprofit, online aggregation of core research in the biological, ecological, and environmental sciences. BioOne provides a sustainable online platform for over 170 journals and books published by nonprofit societies, associations, museums, institutions, and presses. Your use of this PDF, the BioOne Web site, and all posted and associated content indicates your acceptance of BioOne’s Terms of Use, available at www.bioone.org/page/terms_of_use. Usage of BioOne content is strictly limited to personal, educational, and non-commercial use. Commercial inquiries or rights and permissions requests should be directed to the individual publisher as copyright holder.
BioOne sees sustainable scholarly publishing as an inherently collaborative enterprise connecting authors, nonprofit publishers, academic institutions, research libraries, and research funders in the common goal of maximizing access to critical research.
22
Journal
LABORATORY
OBSERVATIONS TO
BRUCE
Department
MARY Ames,
M. CHRISTENSEN,
E. SHELTON, Department Iowa 50011. USA
ON THE
Diro fl/aria
OF RACCOONS
of Wildlife
Diseases
Vol.
14, January,
1978
INSUSCEPTIBILITY
immitis
of Entomology
of Veterinary
Anatomy,
Pharmacology,
and
Physiology,
Iowa
State
University,
Abstract: Two raccoons, Procyon lotor, were exposed to Dirofilania immitis by subcutaneous injection of infective third stage larvae obtained from experimentally-infected Aedes fnivittafus. Nematodes were not recovered from either raccoon when examined at necropsy 223 and 254 days postexposure. Large numbers of adult D. immitis were found in six dogs used as controls. These data indicate that raccoons cannot support the development of D. immitis.
INTRODUCTION
This
Dirofilania immif is has been recovered from the domestic dog (Canis familianis), timber wolf (C. lupus), coyote (C. latnans), red fox (Vulpes fulva), domestic cat (Felis domesfica), muskrat (Ondatra zibethicus), sea lion (Zalophus californianus), orangutan (Pongo pygmaeus), black bear (Ursus amenicanus), beaver (Castor canadensis), wolverine (Gulo luscus), domestic horse (Equus caballus) and man (Homo sapiens). These reports in hosts other than dogs are, almost exclusively, natural infections; the only exception has been the experimental infec-
tion
of domestic
cats.2
natural transmission uncertain, but the rant hosts in which not become sexually
Their
role
in the
of D. immitis is majority are aberthis parasite does mature.
Procyon lotor has never been recorded as a host for D. immif is, but its ability to support a related filarioid nematode, D. fenuis, and its close association with the
Canidae
of the
it might function dog heartworm. near urban areas, large concentrations
Di Journal Paper No. 1955.
Carnivora
suggest
that
as a reservoir host for Raccoons also live in close proximity to of domestic dogs.
No. J-8930
of the Iowa Agriculture
certainly
justifies
to determine function immitis.
the as
MATERIALS
an
ability
definitive
AND
experiment
of raccoons hosts
to
for
D.
METHODS
Two laboratory-reared female raccoons, each two years old, were used in the experiment. They had been previously exposed to infection with a strigeoid trematode (Fibnicola crafena) on
several occasions. They were never exposed to, nor detected as having any other helminth infection. Six mongrel dogs, whelped during the winter and maintained in mosquito-proof mammal rooms, were used as controls. Aedes tniviffatus were maintained as previously described’ and served as the source for D. immif is. Mosquitoes had
become infected by feeding on an infected dog. At 16 days postexposure mosquitoes were dissected in Hank’s balanced salt solution and infective third stage D. immitis recovered from the head and labium were injected subcutaneously
gion with
and Home
into
the
inguinal
re-
of both the dogs and the raccoons a tuberculin syringe and 20-guage Economics
Experiment
Station,
Ames,
iowa.
Project
Journal
of Wildlife
needle. rinsed curate immitis
Diseases
Vol. 14, January,
1978
The syringe and needle several times to insure count of the number injected.
23
were an acof D.
5 months postexposure, 1-ml blood samples were drawn approximately every 14 days and examined by a modified Knott’s technique. Animals were examined at necropsy 213 to 291 days postexposure. AND
their
branches
amined surface the
were
for nematodes of the lungs
lungs
were
and
and lesions. was examined
palpated.
on gross
incisions lobe,
the
to
all
made
exparenrecovered
pulmonary were not
were any lesions
employed
of animals
control
were facilitate
carevi-
examination.
method
posure
animals
the exbecause
for
was
reliable became
infected,
and the recovered juveniles Thirty-six
number of adult D. immitis in relation to the number of injected was quite high. to 40 infective third stage D. immitis were injected into each of six dogs and from 9 to 25 adult D. immitis were recovered from each animal when examined at 213 to 291 days postexposure. Raccoons C and B were exposed to 43 and 46 infective third stage D. immitis, respectively.
and examined arteries and opened
of
The
DISCUSSION
removed All major
amination
dent
Both raccoons were consistently negative for n’iicrofilariae; therefore, raccoon G was examined at 223 days, and raccoon B at 254 days postexposure. The heart, lungs, and entire length of the postcava within the
thorax were thoroughly.
each
chyma. D. immitis from either animal, nor diovascular or pulmonary
Beginning
RESULTS
transverse through
ex-
The and
These raccoons
Numerous
data strongly cannot function
suggest that as hosts for
D. immitis.
Acknowledgements
We thank NIATD
Tom provided
LITERATURE 1.
Cook
for
by
supplying
the
the
U.S.-Japan
raccoons.
The
Cooperative
infected
Medical
used
dog Science
in this
Program-
CITED
CHRISTENSEN,
B. M.
transmission
1977.
of Dinofilania
Laboratory studies on the development and by Aedes tnivittatus. Mosq. News 37:367-
immitis
372. 2.
DONAHOE,
J. M. R. J. Parasit. KLEIN, J. B. and E. D. horse. J. Am. vet.
1975. Experimental 61: 599-605.
immitis.
3. 4.
FOIL,
L. and
beaver, 5.
WILLIAMS, Parasit.
T. Castor
C.
ORIHEL.
canadensis.
J. F. and 62:
STODDARD. med. Ass.
171:
1975.
J. Parasit.
A. W. DADE.
infection
of cats
1977. Dinofilania 354-355. Dinofilania
immitis
for publication
Dirofilania
recovered
(Leidy,
1856)
from
a
in the
61: 433. 1976.
Dinofilania
immitis
174-175.
Received
immitis
with
29 August
1977
in a wolverine.
J.
