Failure of Clostridium chauvoei vaccines to protect against blackleg


Reed, G.A.; Reynolds, L.

Australian Veterinary Journal 53(8): 393-393

1977


Following many deaths of cattle from blackleg in Australia between April 1976 and April 1977 a strain of C. chauvoei was isolated which was not covered by the vaccine. This strain has now been included in a vaccine produced in Australia.

been
resident
in
the
area
for
at
least
five
years,
with
no
previously
noticed
major
illness,
and
was
presented
for
treat-
ment
because
of
swelling
of
the
sheath.
Salient
clinical
features
were
depression,
emaciation,
oedematous
swelling
of
the
sheath
extending
along
the
ventral
abdomen
and
thorax
to
the
pectoral
area,
a
loud
systolic
heart
murmur,
pale
mucous
mem-
branes,
penile
protrusion
and
pollakiuria.
The
urine
contained
small
amounts
of
blood
pigment
and
protein
detectable
by
dipstick
analysis.
Haematological
examination
revealed
severe
anaemia
with
mild
leucopaenia.
The
horse
was
killed
by
the
owner
the
following
day,
there
having
been
no
improvement
after
antibiotic
and
diuretic
therapy,
and
was
not
available
for
post-mortem
examination.
Differential
diagnostic
possibilities
include
congestive
heart
failure,
chronic
parasitism
and
malnutrition,
and
urinary
tract
disease.
However,
as
the
clinical
findings
and
haematology
were
consistent
with
an
acute
haemolytic
episode,
plasma
was
submitted
to
Attwood
Veterinary
Research
Laboratory
for
testing
for
EIA
by
the
agar
gel
immunodiffusion
test
(ACID).
The
plasma
reacted
positively
in
this
test.
This
indicated
that
the
horse
was
infected
with
EIA
virus,
an
unusual
finding
in
Victoria,
where,
of
almost
1000
horses
tested,
only
this
animal
has
reacted
positively
(Harrison
1978).
Samples
tested
front
15
other
horses
in
the
immediate
area
had
no
antibodies
detected
by
ACID.
G.
J.
McINTYRE,
509
Greensborough
Road,
Greensborough,
Victoria
3088
25
October,
1978
References
Albiston,
H.
E.
(1966)
Serv.
Pubis.
Dept.
Hlth.
Aust.
vet.
Hyg.
8:
127.
Harrison,
M..1.
(1978)
Aust.
vet.
.1.
54:
597
Lepherd,
E. E.
(1978)
Aust.
vet.
.1.
54:
42.
Oxer,
D.
T.
(1962)
Aust.
vet.
J.
38:
190.
Oxer,
D.
T.
(1965)
Aust.
vet.
J.
41:
1.
Thomas,
R.
.1.
and
Elder,
Jean
K.
(1978)
Aust.
vet.
J.
54:
456.
PRE-NATAL
INFECTIONS
WITH
LARVAL
TAPEWORMS
There
have
been
several
reports
of
the
occurrence
of
pre-
natal
infection
with
larval
tapeworms.
Taenia
saginata
cysticer-
ci
which,
on
the
basis
of
morphological
development,
were
considered
to
have
been
acquired
pre-natally,
have
been
observed
in
very
young
calves
(McManus
1960;
Slais
and
Mann
1976).
They
have
also
been
found
in
calf
foetuses
(McManus
1963).
Similarly
a
hydatid
cyst
has
been
observed
in
a
new
born
lamb
(Oparin
1958).
Taenia
ovis
has
a
distribution
in
the
muscles
of
sheep
similar
to
that
of
T.
saginata
in
cattle.
Ex-
perimental
infections
either
with
eggs
or
injected
embryos
in
sheep
at
various
times
during
pregnancy,
failed
to
induce
pre-
natal
infections
(Gemmel)
1973).
These
ewes,
however,
were
strongly
immune
to
T.
ovis
due
to
repeated
natural
exposure
to
eggs.
The
possibility
exists
that
these
superimposed
infections
failed
to
survive
long
enough
to
reach
the
foetus
in
ewes
with
a
naturally
acquired
immunity.
The
question
arises
as
to
whethet
or
not
pre-natal
infections
can
occur
in
lambs
carried
by
ewes
that
have
lost
their
immunity.
Such
a
situation
might
occur
from
a
breakdown
during
a
control
program.
In
the
experiment
here,
5-year-old
ewes,
which
had
not
recently
been
exposed
to
the
eggs
of
T.
ovis
were
obtained
from
a
farm
in
an
experimental
control
area
in
the
South
Island
of
New
Zealand.
About
one
month
before
lambing,
6000
ac-
tivated
embryos
of
T.
ovis
were
injected
into
the
jugular
vein
of
3
of
the
ewes
and
the
other
3
received
6000
unhatched
eggs
of
T.
ovis
given
orally
in
a
gelatine
capsule.
The
ewes
and
their
lambs
were
autopsied
and
examined
for
T.
ovis
cysts
when
the
lambs
were
about
one
month
old.
The
number
of
T.
ovis
cysticerci
found
in
the
injected
ewes
and
the
orally
infected
ewes
were
I,
9,
13
and
236,
316,
398
respectively
and
in
one
of
them
315
cysticerci
were
viable.
Despite
the
large
numbers
of
cysticerci
found
throughout
the
muscles
of
the
ewes,
no
organisms
developed
in
any
of
their
8
lambs.
Hence,
it
would
seem
unlikely
that
pre-natal
infections
commonly
occur
during
late
pregnancy
even
when
the
ewe
is
fully
susceptible
to
infection.
R.
J.
SUTTON,
M.
A.
GEMMELL,
Hydatid
Research
Unit,
University
of
Otago
Medical
School,
P.O.
Box
913,
Dunedin,
New
Zealand
19
October
1978
References
Gemmel',
M.
A.
(1973)
Aust.
vet.
.1.
49:
344.
McManus,
D.
(1960)
Vet.
Rec.
72:
847.
McManus,
D.
(1963)
Vet.
Rec.
75:
697.
Oparin,
P.
G.
(1958)
Veterinarija
35:
82.
Slais,
J.
and
Mann,
I.
(1976)
Folia
Parasitologica
23:
321.
FAILURE
OF
CLOSTRIDIUM
CHAUVOEI
VACCINES
TO
PROTECT
AGAINST
BLACKLEG
In
the
June
issue
of
the
Australian
Veterinary
Journal,
Woolcock
and
Frost
(1978)
raised
a
number
of
questions
regar-
ding
Cl.
chauvoei
vaccines
and
the
reported
vaccine
breakdowns.
The
letter
raises
many
questions
for
which
there
are
few
answers.
However,
the
ensuing
comments
may
be
of
in-
terest
to
readers
of
the
Journal.
The
potency
test
for
Cl.
chauvoei
vaccines
in
the
current
edi-
tion
of
the
British
Veterinary
Codex
is
not
considered
to
be
en-
tirely
adequate
because
neither
the
challenge
strain
nor
the
size
of
the
challenge
dose
are
specified
for
the
potency
test.
These
points
were
discussed
last
year
at
a
meeting
of
in-
terested
groups
in
Melbourne.
It
was
agreed
that
the
challenge
strain
should
be
one
which
is
capable
of
breaking
through
low
levels
of
protection
afforded
by
poor
vaccines.
Work
carried
out
at
the
Commonwealth
Serum
Laboratories
by
Chandler
and
co-workers
(1970,
1974,
1975
a,
b)
was
discussed.
On
the
598
Australian
Veterinary
Journal,
Vol.
54,
December,
1978
basis
of
this
work
it
was
agreed
that
the
CSI.
Strain
06207
would
be
accepted
as
the
challenge
strain
for
potency
testing
as
it
appears
to
satisfy
the
above
criteria.
The
National
Biological
Standards
Laboratory
is
at
present
preparing
a
spore
suspension
of
C6207
in
a
form
suitable
for
routine
use
by
vaccine
manufacturers.
The
suspension
will
be
freeze
dried
to
preclude
variation
in
the
challenge
strain.
Woolcock
and
Frost
(1978)
questioned
the
use
of
more
than
one
strain
of
organism
in
a
vaccine.
The
reason
for
this
objec-
tion
is
not
clear
and
it
is
not
unusual
for
the
manufacturer
to
include
2
or
more
strains
of
Cl.
chauvoei
in
a
vaccine.
The
National
Biological
Standards
Laboratory
(NBSL)
was
con-
sulted
by
ICI-TV
L
before
inclusion
of
the
Yeerongpilly
isolate
in
the
vaccine.
The
demonstration
that
vaccine
prepared
from
this
isolate
produced
good
immunity
against
challenge
with
the
homologous
organism
was
considered
by
the
N
I3SL
to
justify
inclusion
of
this
strain
in
the
1C1-TVL
vaccine
if
the
company
wished.
The
approach
adopted
agrees
in
principle
with
the
recom-
mendation
of
Woolcock
and
Frost
(1978)
that
any
vaccine
strain
can
only
be
evaluated
by
animal
inoculation
and
subse-
quent
challenge.
There
is
a
dearth
of
information
on
field
strains
of
Cl.
chauvoei.
There
is,
for
example,
no
information
to
indicate
whether
the
recent
outbreak
of
blackleg
was
due
to
changes
in
the
antigenic
characteristics
of
the
field
strains,
to
unusually
heavy
challenge
or
was
due
to
some
other
reason.
An
additional
problem
is
the
lack
of
a
systematic
reporting
system
which
would
give
early
warning
and
information
on
outbreaks
such
as
that
recently
experienced.
Indeed
it
is
not
even
clear
how
many
of
the
available
vaccine
brands
were
im-
plicated
in
the
recent
breakdown
in
vaccine
protection.
1
would
agree
that
there
is
a
need
for
investigation
and
discussion.
L.
F.
DODSON,
Director,
National
Biological
Standards
Laboratory,
Department
of
Health,
9
Morrissett
St,
Queanbeyan,
New
South
Wales
2620
16
October
1978
References
Woolcock,
J.
B.
and
Frost,
A.
J.
(1978)
Aust.
vet.
J.
54:
319.
Chandler,
H.
M.
and
Gulasekharem,
.1.
(1970)
Aust.
.1.
expt.
Biol.
med.
Sc.
48:
187.
Chandler,
H.
M.
and
Gulasekharem,
.1.
(1974)
J.
gen.
Microbiol.
84:
128.
Chandler,
H.
M.
and
Hamilton,
R.
C.
(1975a)
J.
gen.
Microbiol.
88:
27.
Chandler,
H.
M.
and
Hamilton,
R.
C.
(1975b)
J.
gen.
Microbiol.
88:
179.
SARCOCYSTIS
INFECTION
IN
FIJI
As
a
consequence
of
the
lack
of
indigenous
mammals
in
Fiji,
a
high
proportion
of
the
domestic
livestock
is
descended
from
imported
Australian
stock.
The
importation
of
these
animals
also
introduced
a
number
of
parasites.
It
is
possible
that
Sarcocystis
may
have
arrived
in
this
manner.
Sarcocystis
has
an
obligate
2
host
life
cycle.
In
general,
her-
bivores
and
omnivores
act
as
intermediate
hosts
and
carnivores
as
definitive
hosts.
The
domesticated
food
animals
are
com-
monly
infected
and
dogs,
cats
and
man
can
become
infected
by
the
ingestion
of
the
sarcocysts
in
undercooked
meat.
The
importance
of
Sarcocystis
is
largely
unknown.
In
the
intermediate
host,
certain
species
(S.
cruzi
in
cattle:
S.
ovicanis
in
sheep;
S.
porcifelis
in
pigs)
are
capable
of
causing
serious
disease
(Johnston
et
al
1975;
Dubey
1976).
Several
species
may
cause
mild
disease
whilst
others
are
of
unknown
pathogenicity.
Although
Dubey
(1976)
states
that
Sarcocystis
is
non-
pathogenic
to
the
definitive
host,
the
presence
of
Sarcocystis
in
meat
for
human
consumption
must
be
considered
a
potential
health
hazard
(Seniveratna
1977),
As
no
information
was
available
on
the
extent
of
sar-
cosporidiosis
in
Fiji,
a
survey
was
conducted
on
animals
slaughtered
at
the
main
abattoir.
Over
the
6-month
period,
July-December,
1977,
88
cattle
(7
2
years)
and
99
pigs
(83<one
year;
16>one
year)
were
examined
using
the
peptic
digestion
technique
(Jacob
and
Melton
1957).
The
mean
infection
rate
in
cattle
was
76.1(
1
/
4
and
82.8
6
/o
in
pigs.
The
incidence
of
infection
in
cattle
falls
within
the
range
of
figures
quoted
for
other
coun-
tries.
However,
the
use
of
different
methods
(histological,
digestion
and
serological)
renders
comparisons
of
doubtful
value.
In
pigs,
the
relationship
of
age
to
infection
rate
differs
widely
from
the
findings
in
the
USA
(Seniveratna
1975)
and
Tasmania
(Monday
1975).
By
histological
examination
of
diaphragm
and
myocardium,
Monday
(1975)
found
Sarcocystis
in
1.4°/s
of
pigs
less
than
12
months
of
age
and
16.7°/s
of
those
over
12
months.
Seniveratna
(1975)
used
a
digestion
technique
on
oesophagus
but
failed
to
detect
infection
in
pigs
under
one
year
although
12.7%
of
pigs
over
12
months
harboured
the
parasite.
The
present
survey
presents
a
different
picture
with
infection
rates
being
85.5o/a
in
pigs
less
than
one
year
old
and
68.8°/s
in
those
over
one
year.
It
has
been
suggested
by
these
2
authors
that
access,
by
boars
and
sows,
to
contaminated
pastures
accounted
for
the
greater
fre-
quency
of
infection
in
adults
when
compared
to
younger
stock
which
were
usually
housed.
Such
an
explanation
does
not
ex-
plain
the
findings
in
Fiji
where
neither
adults
nor
young
stock
have
access
to
pasture
and
where
there
appears
to
be
a
greater
prevalence
of
sarcosporidiosis
in
the
younger
pigs.
As
yet
the
reasons
underlying
the
higher
infection
rates
and
their
relation-
ship
to
different
age
groups
in
Fiji's
pigs
have
not
been
elucidated.
N.
R.
RAJU,
R.
MUNRO,
Veterinary
Pathology
Laboratory,
Koronivia,
Fiji
22
August
1978
References
Dubey,
J.
P.
(1976)
J.
Atn.
vet.
med.
Ass.
169:
1061.
.lacob,
L.,
Melton,
M.
L.
(1957)
.1.
Parasit.
43:
(Suppl.)
38.
Johnston,
A.
J.;
Hildebrandt,
P.
K.;
Fayer,
R.
(1975)
Ant.
J.
vet.
Res.
36:
995.
Munday,
B.
L.
(1975)
Aust.
vet.
J.
51:
478.
Seniveratna,
P.
(1977)
Meat
Inspection
Guides,
No.
4.
Australian
Bureau
of
Animal
Health.
Seniveratna,
P.,
Edward,
A.
G.
and
DeGiusti,
D.
L.
(1975)
Am.
J.
vet.
Res.
36:
337.
Australian
Veterinary
Journal,
Vol.
54,
December,
1978
599