SOME EFFECTS OF TICK INFESTATIONS ON JUVENILE NORTHERN BROWN BANDICOOT (ISOODON MACROURUS) Author(s): R. T. Gemmell, G. Cepon, P. E. Green, and N. P. Stewart Source: Journal of Wildlife Diseases, 27(2):269-275. Published By: Wildlife Disease Association DOI: http://dx.doi.org/10.7589/0090-3558-27.2.269 URL: http://www.bioone.org/doi/full/10.7589/0090-3558-27.2.269

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.

Journal

of

Wildlife

27(2),

Dtseases,

© Wildlife

SOME

EFFECTS

NORTHERN R. T. Gemmell,1 Department

BANDICOOT

G. Cepon,

P. E#{149} Green,2

University of Primary

Queensland

4105,

The

ABSTRACT:

monitored

in

effect

infested

or

humerosa,

tick

the

Key

Three

species

tasmani

morbidity,

Ixodid and

brown

of

(Francis,

1969) tant

major

enclosures.

bandicoot,

pests

eases

of

observed

both

do1970).

in

Little,

domestic

vectors

festation

blood

with

food

was intake.

microplus

the

also

observed directly

and

reductions

in

haemogtobin

in

values.

similar

effects

effect

have

Several

our

in

(Backhouse

native

and

the

welt

veloped

bandicoot

Haemaphysalis

tick

on

the

a

milk

effects and

to infections

after

weaning

1971;

Stoddart

1983)

knowledge

In

in

Smith,

in

species have

animals

Boltinger,

been

from

1957;

inob-

of

native

post

partum

each

900

Australia

survived

Collins

ural

et

animals

humerosa,

host Ixodes

predators

deaths,

in

present

for tas-

were 269

92

Only

believed in

study, examined

juvenile the

effect

to determine

150

into

the

of

days

enclosures juveniles

Although

the

carpet

natsnake

goanna

responsible that

this

at

the

and

juveniles

g

40%

Ha!!, 1989).

female

1989).

were

(Gordon, 1979;

released

spi!otes) we

immediately wild

600

including

varius)

1979, vulnera-

(Gemmet!,

(Gemmet!,

(Python anus involved

is a recognised

m2.

1964;

Tyndate-Bis-

Braithwaite,

average were

(Dunnet,

the

study, on

from

disease

both

captivity

a previous

de-

changing

especially

and

last their

Tyndale-Biscoe,

and

and

the

completely

1964; are

in

of

when

are

diet

1969;

are

debilitating

during

is not

Bandicoots

ble

parents,

period

Owen,

first

Mortality

they

adult

an

and

coo and 1984).

a

na-

they

the

is greatest

when

to

that

infestations.

control

Thomson

Marks

when to

lactation,

and

1975,

1984).

of their

vulnerable

physiological

(Doube,

suggested

birds,

independent of

in-

captivity.

The

may captivity,

Vos,

have and

and

observed

parasite

being

infestations

parameters,

de

(1966)

of

at., 1986; Mackerras, 1958, 1959; Priestly, 1915; Weilgama, 1986). Parasites also could affect

mammals

of

haematocrit been

Cribb

tive

marsupials

a tox-

these

and

weighing

haemoprotozoans

served

tick

ho! ocyclus and

phase

influenced

that

To not

important

cluding

was tick-

Haema-

enclosures,

that

Ixodes

Stewart

young

depressed that

and

dis-

animals.

native

the

ticks, blood

macrourus,

effects

steers and of tick in-

with

ticks

metabolism

resulted

O’Kelly

of Bos taurus the effects

associated

by

host’s

1982).

Boo philus

They

in secreted

suggest

particularly

impor-

rickettsiat the

that

festation

of

examined

composition

demonstrated

the

at.,

et

(1970)

results

become the

Johnston,

1963;

also

and

(Stewart

Seifert

These

Isoodon

(Roberts,

haemoprotozoan

in

parameters release into

rate.

animals

are

observed

blood after

inacrourus.

are

they

and various rnacrourus)

were

1979;

1960;

and

ticks

mani

effects

Australia

and Ixodes holocyclus. Bandicoots released into tick-infested rate (1.8 versus 2.5 g/day increase in body weight), a reduced and an increased number of white blood cells when compared

animals are two-fold: heavy infestations have a serious debilitating effect on host

4067, Brisbane, Institute,

INTRODUCTION

wild

Pathogenic

I.

growth

ticks

mestic

juvenile

Northern

words:

mortality,

of

St. Lucia, Research

on body weight bandicoots (Isoodon

brown

enclosures.

Ixodes

health

MACROURUS)

and N. P. Stewart2

infestations

enclosures showed a reduced growth haematocrit value (27.4 versus 40.0%) with bandicoots released into tick-free influence

(ISOODON

of Queensland, Industry, Animal

northern

tick-free

ON JUVENILE

Australia

of

juvenile

physalis

INFESTATIONS

BROWN

of Anatomy, Department

2

Yeerongpilly,

OF TICK

pp. 269-275 Association 1991

1991,

Disease

other

(Varfor

factors

mortality. of tick

some were In

the

infestations whether

they

270

JOURNAL

OF WILDLIFE

contributed venile

to Isoodon

DISEASES,

the

high

VOL. 27, NO. 2, APRIL

mortality

in

MATERIALS

(Gemmetl,

the effect

of ticks

wild bandicoots with those enclosures, similar samples weekly

AND METHODS

Methods of capture and maintenance northern brown bandicoot, have been previously

ju-

macrourus.

1991

1982,

1989).

on juvenile

of the published

To

examine

bandicoots,

moth-

ers with young 45- to 50-days-old were removed from the external breeding enc!osures and housed in cages. Young were weaned at day 60 of lactation, at which time each young was individually housed and thereafter weighed

from

been

housed

sures

for

eight

adult

in the

at least

were released into tick-infested encloand six juveniles into adjacent tick-free enclosures. The latter enclosures were surrounded by a water moat to prevent the entry of ticks. sures

The

yards

weekly

and

with

bandicoots

Taktic

were

EC

(Schering

sprayed Pty.

bi-

Ltd.,

57-

79 Anzac Parade, Kensington, 2033, Australia), 15 ml in 2 1 of water. Both groups of bandicoots received similar food and water ad libitum (Gemmell,

1982,

1989).

Bandicoots were lightly anaesthetised with a ‘Hatothane’ (ICI Australia Operations Pty. Ltd., Melbourne, 3000, Austra!ia)-oxygen mixture for ease of handling, blood sampling and weighing. Blood samples were obtained weekly from the 13 juveniles by heart puncture 3 wk prior to

release into the external enclosures after release. Blood samples were 9 wk after release. Each bandicoot

and for 6 wk also obtained was returned

to the enclosure Leukocytes

examination. an improved

(Carolina ton,

immediately were counted

Biological

North

Carolina

after using

Supply 27215,

Company, USA)

Neubauer

Burlinghae-

matocytometer. The haematocrit va!ue was measured using gold seat heparinized micro haematocrit tubes (Clay Adams, Beeton Dickinson and Company, Parispanny, New Jersey 07054, USA). Blood films for differential white cell counts and red cell morphology were stained with Jenner-Giemsa stain (McClung, 1939).

Differences

in body

weight,

haematocrit

val-

ue and the number of white blood cells in both groups of juveniles were analysed by ANOVA to determine whether the differences were significant. The level of a was estabtished at P 0.05. Blood samples were obtained from 15 adult bandicoots trapped in the environs of Brisbane, Queensland, Australia (27#{176}24’S, 152#{176}45’E). On the day of capture each bandicoot was lightly anaesthetised with ‘Hatogen’-oxygen mixture, weighed and a blood sample obtained by cardiac

puncture.

To

compare

these

samples

from

bandicoots

outside

which

tick-infested

had

encto-

6 mo.

To determine numbers and species of ticks present on animals in enclosures the following procedure was adopted. Each week, either two or three adult bandicoots were transferred from an enclosure and placed in wire mesh cages (30 x 40 x 50 cm) surrounded by a water moat. All ticks fatting from each bandicoot over a 7 day period from October 1984 and March 1986 were collected for identification.

weekly. Thirteen juvenile bandicoots, each approximately 600 g, were examined for 3 wk prior to release into external enclosures. Seven juveniles

from bandicoots in also were obtained

RESULTS

Three species of from adult bandicoots H. humerosa, These ticks

were

ticks

were obtained the enclosures,

in

I. tasrnani found

and I. ho! ocyclus. throughout the year

with the majority of adult present in the latter one-half

stages being of the year

(January Blood volume

1). packed of adult

through parameters, and white

bandicoots side

and

enclosures

When

June, Table including cell count adults were

juvenile

housed

by

in body housed

the

(Table

bandicoots

ferred from cages into weight decreased initially tick status but recovered levels

in

similar

cell wild out2).

were

trans-

enclosures, body irrespective of to pre-enclosure

3 wk (Fig. 1). Although variation weight was greater in bandicoots in tick-free enclosures, the growth

rate of this group was greater than that of the juveniles housed in enclosures with ticks. Within 6 wk of release, the mean body weights of bandicoots housed in tickfree

enclosures

resenting bandicoot/day

increased

104

by

g,

rep-

a mean weight gain of 2.5 g/ (Fig. 1). Over a similar pe-

nod, seven bandicoots released into tickinfested enclosures had a total mean body weight gain of 74 g, or 1.8 g/bandicoot/ day (Fig. the white matocrit During significant bers for

1). There also blood cell count values between the

3 wk

difference the seven

was variation in (WBC) and haethe two groups.

in cages

there

between bandicoots

to be housed in enclosures the six bandicoots which

WBC which with

were

was

no

numwere

ticks, and to be housed

GEMMELL

1.

TABLE

to March

The 1986

number expressed

of bandicoots

and species of ticks as the number of

examined

per

present larvae,

ET AL-EFFECTS

on bandicoots nymphs, males,

OF TiCKS

ON BANDICOOTS

housed in enclosures and females obtained

271

from October 1984 from the number

month. Number

Hae maphys L’

ails humerosa

Nb

Ixodes

M

Fd

Ixod

lasmani

L

N

F

M

of bandicoots

es hoiocycius

L

N

M

F

exammed

2

27

11

8

8

1984

Oct

-

153

901

71

32

68

-

1

Nov

18

6

39

182

120

10

-

34

-

1

Dec

19

25

14

27

120

23

25

28

-

-

10

16

19

-

12

109

1

-

-

-

3

-

-

14

-

-

7

1985 Jan

26

226

Feb

4

9

10

3

151

30

Mar

6

4

-

1

145

34

Apr

2

33

-

6

303

123

-

-

4 -

1

52

49

-

-

1

57

223

-

-

8

43

166

-

May

-

Jun

-

Jul

17

35

Aug

-

13

4

15

97

-

4

5

18

33

37

-

1

7

46

55

21

4

Sep

1

Oct

-

-

8

-

225

1

313

103

-

-

8

2

11

474

-

-

10

5

>1,000

21

7

213

1

6

13

51

1

4

8

6

222

1

6

10

2

3

8

-

44

4

8

10

-

20

-

4

8

30

-

9

-

1

8

-

-

1

-

1

8

-

1

10

9 1

10

4

Nov

7

3

7

11

31

12

-

Dec

8

19

6

11

46

66

-

2

20

-

1986

82

25

78

19

13

-

2

30

2

Feb

3

56

4

36

11

8

-

4

48

12

Mar

8

18

28

29

3

-

Jan

41

50

8

1,200

-

-

-

8

-

-

6

-

-

8

‘L, larva. N,

nymph.

M, male. F, female.

in

tick-free

0.51,

P

nificant

enclosures

2. samples)

2).

in

bandicoots

TABLE

(ANOVA,

Fig.

increase

seven

24

0.05;