Journal
Fish Mortality Causes Robert
in the Mississippi
Catfish
M. Durborow,’3
Peter
The
ABSTRACT:
in
words: catfish,
catfish,
diseases
1988
fish
mortality
summary
talities.
and
mortality punctatus,
in 1988:
aquacultural
the
acreage
to
tatus)
culture
channel
United
with
value health
et of
care
over
al.
the
Mississippi
vice
(MCES;
USA
and Belzoni, Mississippi the catfish industry
in
billion
Ser38776,
39038, USA) several million
catfish disease gens and other
during management
tributing to fish mortalities and appear in Table 1. The
reported
in 1988 occurrences diseases
others;
to MCES
and are
for
represent diagnostic
the
example,
winter
kill
(Table 1) were regarded to the fish’s diseased always solely responsible
is often
ESC
affects
all
ESC
significant per day 1,000,000
mortalities in ponds fish. The
in catfish
has
mune
as constate and for mor-
Additionally,
1987)
cat-
with
June,
major
peak
Septem-
epizootics
and
may
cause
to 2,000 80,000 of by
Plumb
contributor
fish to ESC
Jarboe
et
(1985),
and
to chan-
was Internal
external CytophAeromonas sp.
ranked
third.
bacteria.
for
mor-
in fingerlings
described
mortality
system
the
catfish
of 500 containing pathogenicity
been
bacteria
difficult
was
of channel
et a!.,
second
most
and
often
in May,
occurring October.
is
(Freund et a!., 1990). occur between 22 and
and Aeromonas portunistic and cause the Fall and Spring. temperatures (about
not
sizes
more
sp.
feel that All listed
the
(ESC)
to channel
it occurs
complex
of
than
occurred
cases)
outbreaks
The
cases
all
contributor
nel catfish aga sp.
laboratories
many farmers treatment.
of
28 C (Francis-Floyd
recorded
do not reflect actual disease in the catfish industry. Some submitted less frequently than
submitted because there is no effective etiologies tributing were not
data
were
causes
catfish
ictaluri
(48%
and
as
ictaluri (Hawke, 1981; MacMillan,
al.,
et
al. (1984), Miyazaki Shotts et al. (1986).
1988. Pathofactors con-
cases
Hawke
Edwardsiella
ber
dollars each year based on an estimated $1,000.00 to $10,000.00 savings to the farmer per diagnosed case. MCES fish disease diagnostic laboratories examined 2,456
fish’s
cases caused
higher
of
(up to 15 centimeters) Epizootics of ESC
by
the
Many this
potential
Edwardsiella
1985).
but
or
di-
number.
1979;
fish,
dol-
Extension Mississippi
1 to be
Table
feed
were regarded
mortality. etiologies;
septicemia
talities.
not
of
by
leading
to
were
number
frequently
with
but
in case
caused
provided
Cooperative Stoneville,
submitted
cause of multiple
total
of
example,
contributors
the sole involved mortality
depunc-
1989),
,
2.1
service
acres
major
state,
Enteric
States
91 ,583 (Ictalurus
catfish (Brunson
estimated Fish
as
1), for
diseased
the
aquaculture.
amount
(Table
agnosed
investigations, farm-raised
treatment,
leads
voted
Insufficient
crowding
total Fish Icta!urus
Mississippi
saves
Industry
M. David Crosby,’ and Timothy D. Santucci,’ ‘Department of Wildlife Extension Service, P.O. Box 142, Stoneville, Mississippi 38776, USA; 2 Department Cooperative Extension Service, P.O. Box 631, Belzoni, Mississippi 39038, Research Center, Kentucky State University, Frankfort, Kentucky 40601, USA
1988.
Key channel
lars.
27(1), 1991, pp. 144-147 Disease Association 1991
W. Taylor,2
for the catfish (Icta!urus punctatus) industry in Mississippi is presented. In 1988, 2,456 cases were submitted to Mississippi Cooperative Extension Service fish disease laboratories at Belzoni and Stoneville. Bacterial infection caused by Edwardsie!!a icta!uri was the leading cause of catfish mortality. Descriptions and treatments are presented for bacterial, parasitic, viral and other diseases affecting Mississippi farm-raised
an
Farming
DIseases, © Wildlife
and Treatments
and Fisheries, Mississippi Cooperative of Wildlife and Fisheries, Mississippi USA; Present address: Aquaculture
catfish
of Wildlife
is optima! bacterial during
Cytophaga
sp. complex are opmortalities mostly in During hot summer 30 C) the catfish immaking pathogens cold
winter
it
more
to thrive. temper-
atures (below 14 C) bacterial pathogens are seldom able to affect catfish and are 144
SHORT
TABLE catfish
1. Etiologies contributing examined by the Mississippi
tension
Service
in
to mortalities Cooperative
of Ex-
1.
TABLE
COMMUNICATIONS
Continued.
1988. Number cases
Etiology Number
Etiology
cases
ictaluri
Miscellaneous
Edwardsiella Cytophaga Aeromonas
sp. external
637
sobria
356
Cytophaga
sp.
221
1,169
systemic
Cytophagaceae
(other
Cytophaga
sp.)
Winter
kill
Severe
anemia
Handling
Inadequate
not
teriostatic fish food
3
tions.
Terramycin Lee’s Summit,
1
New
304 221
Ichthyobodo Trichophrya Chilodonella Ichthyophthirius Heteropolaria
sp.
144
met-30
sp.
143
et a!.
sp.
catfish
virus
disease
Saprolegnia
sp.
Nitrite
pH
stress
oxygen
1985).
3
er, Ichthyophthirius in highest mortalities
efficacy
of Ro-
by Plumb (1986).
Trichodina
Ambiphyrya encountered
Potassium
sp.
205
on alternate three chemicals
1 1
Nutritional
of feed
Channel causes
10
sp. of I. multifilis,
on
preferred Due
catfish
virus in
sulfate
chemicals
ap-
food
fish.
treatment
to the complex it must be treated of the above is achieved.
days with any until control
mortalities
fre-
Howev-
copper
Trichophrya cycle
most
multifihis (Ich) results on a per case basis.
is the
sulfate
for life
hardness
amount
are the protozoans.
permanganate,
356
7
disease
sp.
and formalin are the only proved by FDA to be used
53
depletion
elevation
Insufficient
and
parasites causing sigare protozoa (Rogers,
MacMillan,
quently
26
Gas bubble
orNut-
USA)
demonstrated Bowser et al.
and
quality
Insufficient
been and
4
1 1
Ammonia oxygen
,
Pfizer, Inc., 64081, USA) are
The
of the catfish mortalities
Copper
Dissolved
and Inc.
07110,
made.
8
Fungus
Low
has (1987)
1985;
Virus
External
into infec-
gills
Henneguya sp. Lernaea sp. Apiosoma sp. Gyrodactylus sp. Bodomonas sp.
Water
are
Most nificant
23
incorporated bacterial
(oxytetracycline, Missouri
mendations
gill disease
Channel
Jersey
Bac-
the two antibiotics approved by the FDA for use in catfish. Bacteria recovered from sick fish are examined for sensitivity to these antibiotics before treatment recom-
Proliferative
72
problem.
Romet-30 (sulfadimethoxine metopnim, Hoffman-LaRoche ley,
1
of a disease
antibiotics are for controlling
1 1
127
part
1
376
on
sample
4
6
multifilis
2 121
usually
sp.
6
condition
Unknown
Parasites
Monogenea
9 suspected
“Gas-in-gut”
80
sp.
44
26
Toxicity
154
sp.
278
Crowding
than
A. hydrophila Plesiomonas shigelloides Edwardsiella tarda Pseudomonas sp. Aeromonas sp. Enterobacter sp. Acinetobacter sp. Flavobacterium sp. Pseudomonas fluorescens Escherichia coli Citrobacter sp. Shigella sp. Hafnia sp. Vibrio sp.
of
of
Bacteria
Trichodina Ambiphrya
145
disease
fingerlings
(CCV) 15 cm
in length when pond temperatures are above 20 C (Plumb, 1973, 1978). No treatment exists for this virus, but losses can be reduced agement
significantly (Crosby
and
under proper manDurborow, 1988).
JOURNAL
146
OF WILDLIFE
Saprolegnia winter mortality (Durborow In
sp. is usually syndrome
and
Crosby,
advanced
disease mottled
ESEASES,
associated (winter
with kill)
1988).
stages
of
(PGD), gills appearance
VOL. 27, NO. 1, JANUARY
proliferative
gill
have a red and like ground
white ham-
burger meat, hence the name hamburger gill disease. This ground hamburger appearance results from swelling of the gill and loss of gill filament structure due to a breakdown of cartilage (Duhamel et a!., 1986). The filaments are not well defined structurally A myxosporean cartilage
and and
been
proposed
PGD
(Hedrick PGD
1989).
appear parasite other as
mashed associated parts
the
water
et al., 1989; occurs mostly
water quality
of
from into
quently brings the water level
the
causative
temperatures are between and occurs more often in Fall. Although experimentally pumping
together. with the has of
Groff when
et a!., water
15 and 20 Spring than unproven,
a pond
the
gill agent
with
affected
losses under is increased
C, in
good
pond control about
freafter 0.3 m
1991
(Durborow idizes which
and
Crosby,
1989).
hemoglobin to prevents transport
blood spite water. yates
a 20-25 mg/i their ponds to a sudden nitrite Total hardness should ness
growth
chloride concentration provide protection increase. of catfish hatchery
be at least
5 mg/i
CaCO3.
levels below 5 mg/l, and survival and
as well,
fry eggs
(CaCl2 2H2O) solution to (Durborow et a!., 1989).
form of ammonia exceeds borow, 1988). Frequency nia
occurrences
can
at reasonable rates ha). High ammonia reduced
slightly
0.4 mg/i of high
be reduced
by feeding
(not exceeding concentrations by
(Dunammo-
diluting
112 kg/ can be with
water
from an adjacent pond or well. In addition, fertilizing has been observed to reduce ammonia by increasing phytoplankton growth and activity, resulting in ammonia absorption. High nitrite concentrations can cause brown blood mia) in channel chloride
to nitrite
disease catfish ion
Severe
anemia
listed
in
in channel
ably have
exist. included
water
Table
catfish
Treatment maintaining
to nitrite ratio feed, although
and/or often
1 refers commonly
a!., 1989) have severe anemia. etiologies prob-
recommendations a high chloride changing type of neither of these rec-
ommendations so!ves the problem. In catfish with “gas-in-gut” condition, the intestine was distended three to eight times the normal diameter (Table 1). In these cases, no infection or water qualityrelated talities
problem was were attributed
condition.
No
identified, so morto the “gas-in-gut”
treatment LITERATURE
the
F.
ratio
6:1
tiated sulfonamide
below
have poorer do not hatch
called “white-lip” or “no-blood” disease. Hematocnits are often as low as 1 to 9% (Plumb et a!., 1986). Contaminated feed (Butterworth et al., 1986) and high nitrite
(methemoglobineespecially when falls
water At hard-
hatchery
‘
in the water (Tucker et been implicated in causing However, other unknown
catfish
in against
sometimes becoming enlarged and due to insufficient level of calcium water. The deficiency can be corby adding a calcium chloride
opaque in the rected
ditions.
pond-raised
in the
nitrite ions entering fish through the gills. Catfish farmers in the Mississippi Delta strive to maintain at least a 6 to 1 chloride to nitrite ratio, and frequently keep at least
to a condition
However,
ox-
to organs, thus suffocating fish in of adequate dissolved oxygen in the Adding salt (NaC1) to ponds elechloride concentrations and reduces
(approximately 48 hr of pumping with a re-lift pump into an 8 ha pond). Ammonia occurs in catfish ponds frequently at levels that are considered adverse or even lethal under laboratory conbecome acclimated to high ammonia, and diagnostic laboratories usually implicate ammonia as a disease-causing agent only when the concentration of the un-ionized
Nitrite
methemag!obin of oxygen
BOWSER,
P. STILES,
H.,
A.
D.
AND
has
H.
FRANCIS-FLOYD,
of
Edwardsiella
MAESTRONE.
therapy
found.
CITED
MUNSON,
G.
been
1986.
Poten-
ic-
SHORT
taluri
infection
in channel
ricultural
and
Research
Report.
Mississippi
catfish.
Forestry Mississippi
State,
Mississippi
Experiment State
Mississippi
Ag-
Station
M. W., R. M. DURBOROW, M. D. CROSBY, P. W. TAYLOR. 1989. Status of fish farming in Mississippi-April 1989. In For fish farmers, Extension
Service.
Mis-
sissippi sissippi
State University, Mississippi State, Mis1, 10 pp. BUTFERWORTH, C. E. , JR., J. A. PLUMB, AND J. M. GRIZZLE. 1986. Abnormal folate metabolism in feed-related anemia of cultured channel catfish. Proceedings
of the
Society
for
Experimental
Bi-
ology
and Medicine 181: 49-58. CROSBY, M. D. , AND R. M. DURBOROW. 1988. Channel catfish virus. Mississippi Cooperative Extension Service Information Sheet 1383, Mississippi State University, Mississippi State, Mississippi, 2 pp. G. E. , M. L. KENT, N. 0. DYBDAL, AND H. P. HEDRICK. 1986. Henneguya exilis Kudo associated with granulomatous branchitis of channel catfish Ictalurus punctatus (Rafin-
DUHAMEL,
esque).
Veterinary
Pathology
23:
354-361.
H. M. 1988. Ammonia in fish ponds. Mississippi Cooperative Extension Service Information Sheet 1333, Mississippi State University, Mississippi State, Mississippi, 2 pp. AND M. D. CROSBY. 1989. Brown blood
DURBOROW,
disease. vice
Mississippi
Information
Cooperative Sheet
1390,
Extension Mississippi
of
to increase
water
1989.
Use
hardness
of calcium in catfish
SerState
Sphaerospores
observed
in the
kidney
of
Systematic
8: 389-392.
1973.
of
Effects
fingerling
of temperature channel
on
1978.
.
disease.
Epizootiology Marine
, S. A. HOROWITZ, Feed-related anemia (Ictalurus punctatus).
MAESTRONE,
W.
cipal
A.
(ed).
225,
Station,
Auburn E.
B.,
40:
virus
26-29.
W. A. ROGERS. in cultured channel
AND
Aquaculture
B. sulfonamide
51:
Protozoan
1986.
catfish 175-179. 1987.
QUINLAN.
to control
infection in Aquaculture
of farm
Southern
Number SHOTTS,
1985.
diseases
catfish
Review
AND
Use of a potentiated wardsiella ictaluri (Ictalurus punctatus). ROGERS,
of channel
Fisheries
channel 62:
Ed-
catfish 187-194.
In Prin-
parasites.
raised
mor-
(Ictalurus with chanResearch
catfish
punctatus) experimentally infected nel catfish virus. Journal of Fisheries Board of Canada 30: 568-570.
G.
of
Journal
31 : 396-400. T. MCDOWELL,
Diseases
J. A.
chloride hatcheries.
International
, AND J. M. GROFF. Sphaerospora ictaluri n. sp. (Myxosporea: Sphaerosporidae) observed in the kidney of channel catfish, Ictalurus punctatus Rafinesque. Abstract in Fish health workshop. American Fisheries Society, Annapolis, Maryland, p. 21. JARBOE, H. H. , P. H. BOWSER, AND H. H. ROBINETTE. 1984. Pathology associated with a natural Edwardsiella ictaluri infection in channel catfish (Ictalurus punctatus Rafinesque). Journal of Wildlife Diseases 20: 352-354. MACMILLAN, J. H. 1985. Infectious diseases. In Channel catfish culture, C. S. Tucker (ed). Elsevier, New York, New York, pp. 405-496. MIYAZAKI, T. , AND J. A. PLUMB. 1985. Histopathology of Edwardsiella ictaluri in channel catfish, Ictalurus punctatus (Rafinesque). Journal of
tality
Mississippi Cooperative Extension Service Information Sheet 1388, Mississippi State University, Mississippi State, Mississippi, 2 pp. FRANCIS-FLOYD, H., M. H. BELEAU, P. WATERSTRAT, AND P. R. BOWSER. 1987. Effect of temperature on the clinical outcome of infection with Edward.siella ictaluri in channel catfish. Journal of the American Veterinary Medical Association 191: 1413-1416. FREUND, J. D., R. M. DURBOROW, J. H. MACMILLAN, M. D. CROSBY, T. L. WELLBORN, P. W. TAYLOR, AND T. E. SCHWEDLER. 1990. Utilizing diagnostic laboratory records to monitor the occurrence of entenic septicemia of channel catfish in Mississippi. Journal of Aquatic Animal Health. In press. GROFF, J. M., T. MCDOWELL, AND H. P. HEDRICK. 1989.
FHS/AFS
1989.
Fish
Mississippi State, Mississippi, 2 pp. . 1988. Monitoring winter kill conditions can cut losses. The Catfish Journal December 1988: 9. ,T. L. WELLBORN, JR., P. W. TAYLOR, AND CROSBY.
catfish.
Bacteriology HEDRICK, H. P.
AND
D.
punctatus).
5.
J. P. 1979. A bacterium associated with disease of pond cultured channel catfish, Ictalurus punctatus. Journal of the Fisheries Hesearch Board of Canada 36: 1508-1512. ‘ A. C. MCWHORTER, A. G. STEIGNERWALT, AND D. J. BRENNER. 1981. Edwardsiella ictaluri sp. ; the causative agent of entenic septicemia
PLUMB,
University,
M.
(Ictalurus
17:
147
HAWKE,
University,
1 1, 3 pp.
AND
Cooperative
catfish
Newsletter
BRUNSON,
Mississippi
channel
COMMUNICATIONS
J. A. Plumb
catfish,
Cooperative Services Bulletin Alabama Agricultural Experiment University,
V. S. BLAZER,
Alabama, AND
W.
pp.
D.
24-32.
WALTMAN.
1986. Pathogenesis of experimental Edwardsiella ictaluri infections in channel catfish (Ictalurus punctatus). Canadian Journal of Fisheries and Aquatic Sciences 43: 36-42. TUCKER, C. S., H. FRANCIS-FLOYD, AND M. H. BE1989.
LEAU.
Nitrite-induced
anemia
catfish, Ictalurus punctatus Rafinesque. letin of Environmental Contamination icology 43: 295-301. Received
for
publication
12 January
1990.
in channel
The Buland Tox-
Fish Mortality Causes Robert
in the Mississippi
Catfish
M. Durborow,’3
Peter
The
ABSTRACT:
in
words: catfish,
catfish,
diseases
1988
fish
mortality
summary
talities.
and
mortality punctatus,
in 1988:
aquacultural
the
acreage
to
tatus)
culture
channel
United
with
value health
et of
care
over
al.
the
Mississippi
vice
(MCES;
USA
and Belzoni, Mississippi the catfish industry
in
billion
Ser38776,
39038, USA) several million
catfish disease gens and other
during management
tributing to fish mortalities and appear in Table 1. The
reported
in 1988 occurrences diseases
others;
to MCES
and are
for
represent diagnostic
the
example,
winter
kill
(Table 1) were regarded to the fish’s diseased always solely responsible
is often
ESC
affects
all
ESC
significant per day 1,000,000
mortalities in ponds fish. The
in catfish
has
mune
as constate and for mor-
Additionally,
1987)
cat-
with
June,
major
peak
Septem-
epizootics
and
may
cause
to 2,000 80,000 of by
Plumb
contributor
fish to ESC
Jarboe
et
(1985),
and
to chan-
was Internal
external CytophAeromonas sp.
ranked
third.
bacteria.
for
mor-
in fingerlings
described
mortality
system
the
catfish
of 500 containing pathogenicity
been
bacteria
difficult
was
of channel
et a!.,
second
most
and
often
in May,
occurring October.
is
(Freund et a!., 1990). occur between 22 and
and Aeromonas portunistic and cause the Fall and Spring. temperatures (about
not
sizes
more
sp.
feel that All listed
the
(ESC)
to channel
it occurs
complex
of
than
occurred
cases)
outbreaks
The
cases
all
contributor
nel catfish aga sp.
laboratories
many farmers treatment.
of
28 C (Francis-Floyd
recorded
do not reflect actual disease in the catfish industry. Some submitted less frequently than
submitted because there is no effective etiologies tributing were not
data
were
causes
catfish
ictaluri
(48%
and
as
ictaluri (Hawke, 1981; MacMillan,
al.,
et
al. (1984), Miyazaki Shotts et al. (1986).
1988. Pathofactors con-
cases
Hawke
Edwardsiella
ber
dollars each year based on an estimated $1,000.00 to $10,000.00 savings to the farmer per diagnosed case. MCES fish disease diagnostic laboratories examined 2,456
fish’s
cases caused
higher
of
(up to 15 centimeters) Epizootics of ESC
by
the
Many this
potential
Edwardsiella
1985).
but
or
di-
number.
1979;
fish,
dol-
Extension Mississippi
1 to be
Table
feed
were regarded
mortality. etiologies;
septicemia
talities.
not
of
by
leading
to
were
number
frequently
with
but
in case
caused
provided
Cooperative Stoneville,
submitted
cause of multiple
total
of
example,
contributors
the sole involved mortality
depunc-
1989),
,
2.1
service
acres
major
state,
Enteric
States
91 ,583 (Ictalurus
catfish (Brunson
estimated Fish
as
1), for
diseased
the
aquaculture.
amount
(Table
agnosed
investigations, farm-raised
treatment,
leads
voted
Insufficient
crowding
total Fish Icta!urus
Mississippi
saves
Industry
M. David Crosby,’ and Timothy D. Santucci,’ ‘Department of Wildlife Extension Service, P.O. Box 142, Stoneville, Mississippi 38776, USA; 2 Department Cooperative Extension Service, P.O. Box 631, Belzoni, Mississippi 39038, Research Center, Kentucky State University, Frankfort, Kentucky 40601, USA
1988.
Key channel
lars.
27(1), 1991, pp. 144-147 Disease Association 1991
W. Taylor,2
for the catfish (Icta!urus punctatus) industry in Mississippi is presented. In 1988, 2,456 cases were submitted to Mississippi Cooperative Extension Service fish disease laboratories at Belzoni and Stoneville. Bacterial infection caused by Edwardsie!!a icta!uri was the leading cause of catfish mortality. Descriptions and treatments are presented for bacterial, parasitic, viral and other diseases affecting Mississippi farm-raised
an
Farming
DIseases, © Wildlife
and Treatments
and Fisheries, Mississippi Cooperative of Wildlife and Fisheries, Mississippi USA; Present address: Aquaculture
catfish
of Wildlife
is optima! bacterial during
Cytophaga
sp. complex are opmortalities mostly in During hot summer 30 C) the catfish immaking pathogens cold
winter
it
more
to thrive. temper-
atures (below 14 C) bacterial pathogens are seldom able to affect catfish and are 144
SHORT
TABLE catfish
1. Etiologies contributing examined by the Mississippi
tension
Service
in
to mortalities Cooperative
of Ex-
1.
TABLE
COMMUNICATIONS
Continued.
1988. Number cases
Etiology Number
Etiology
cases
ictaluri
Miscellaneous
Edwardsiella Cytophaga Aeromonas
sp. external
637
sobria
356
Cytophaga
sp.
221
1,169
systemic
Cytophagaceae
(other
Cytophaga
sp.)
Winter
kill
Severe
anemia
Handling
Inadequate
not
teriostatic fish food
3
tions.
Terramycin Lee’s Summit,
1
New
304 221
Ichthyobodo Trichophrya Chilodonella Ichthyophthirius Heteropolaria
sp.
144
met-30
sp.
143
et a!.
sp.
catfish
virus
disease
Saprolegnia
sp.
Nitrite
pH
stress
oxygen
1985).
3
er, Ichthyophthirius in highest mortalities
efficacy
of Ro-
by Plumb (1986).
Trichodina
Ambiphyrya encountered
Potassium
sp.
205
on alternate three chemicals
1 1
Nutritional
of feed
Channel causes
10
sp. of I. multifilis,
on
preferred Due
catfish
virus in
sulfate
chemicals
ap-
food
fish.
treatment
to the complex it must be treated of the above is achieved.
days with any until control
mortalities
fre-
Howev-
copper
Trichophrya cycle
most
multifihis (Ich) results on a per case basis.
is the
sulfate
for life
hardness
amount
are the protozoans.
permanganate,
356
7
disease
sp.
and formalin are the only proved by FDA to be used
53
depletion
elevation
Insufficient
and
parasites causing sigare protozoa (Rogers,
MacMillan,
quently
26
Gas bubble
orNut-
USA)
demonstrated Bowser et al.
and
quality
Insufficient
been and
4
1 1
Ammonia oxygen
,
Pfizer, Inc., 64081, USA) are
The
of the catfish mortalities
Copper
Dissolved
and Inc.
07110,
made.
8
Fungus
Low
has (1987)
1985;
Virus
External
into infec-
gills
Henneguya sp. Lernaea sp. Apiosoma sp. Gyrodactylus sp. Bodomonas sp.
Water
are
Most nificant
23
incorporated bacterial
(oxytetracycline, Missouri
mendations
gill disease
Channel
Jersey
Bac-
the two antibiotics approved by the FDA for use in catfish. Bacteria recovered from sick fish are examined for sensitivity to these antibiotics before treatment recom-
Proliferative
72
problem.
Romet-30 (sulfadimethoxine metopnim, Hoffman-LaRoche ley,
1
of a disease
antibiotics are for controlling
1 1
127
part
1
376
on
sample
4
6
multifilis
2 121
usually
sp.
6
condition
Unknown
Parasites
Monogenea
9 suspected
“Gas-in-gut”
80
sp.
44
26
Toxicity
154
sp.
278
Crowding
than
A. hydrophila Plesiomonas shigelloides Edwardsiella tarda Pseudomonas sp. Aeromonas sp. Enterobacter sp. Acinetobacter sp. Flavobacterium sp. Pseudomonas fluorescens Escherichia coli Citrobacter sp. Shigella sp. Hafnia sp. Vibrio sp.
of
of
Bacteria
Trichodina Ambiphrya
145
disease
fingerlings
(CCV) 15 cm
in length when pond temperatures are above 20 C (Plumb, 1973, 1978). No treatment exists for this virus, but losses can be reduced agement
significantly (Crosby
and
under proper manDurborow, 1988).
JOURNAL
146
OF WILDLIFE
Saprolegnia winter mortality (Durborow In
sp. is usually syndrome
and
Crosby,
advanced
disease mottled
ESEASES,
associated (winter
with kill)
1988).
stages
of
(PGD), gills appearance
VOL. 27, NO. 1, JANUARY
proliferative
gill
have a red and like ground
white ham-
burger meat, hence the name hamburger gill disease. This ground hamburger appearance results from swelling of the gill and loss of gill filament structure due to a breakdown of cartilage (Duhamel et a!., 1986). The filaments are not well defined structurally A myxosporean cartilage
and and
been
proposed
PGD
(Hedrick PGD
1989).
appear parasite other as
mashed associated parts
the
water
et al., 1989; occurs mostly
water quality
of
from into
quently brings the water level
the
causative
temperatures are between and occurs more often in Fall. Although experimentally pumping
together. with the has of
Groff when
et a!., water
15 and 20 Spring than unproven,
a pond
the
gill agent
with
affected
losses under is increased
C, in
good
pond control about
freafter 0.3 m
1991
(Durborow idizes which
and
Crosby,
1989).
hemoglobin to prevents transport
blood spite water. yates
a 20-25 mg/i their ponds to a sudden nitrite Total hardness should ness
growth
chloride concentration provide protection increase. of catfish hatchery
be at least
5 mg/i
CaCO3.
levels below 5 mg/l, and survival and
as well,
fry eggs
(CaCl2 2H2O) solution to (Durborow et a!., 1989).
form of ammonia exceeds borow, 1988). Frequency nia
occurrences
can
at reasonable rates ha). High ammonia reduced
slightly
0.4 mg/i of high
be reduced
by feeding
(not exceeding concentrations by
(Dunammo-
diluting
112 kg/ can be with
water
from an adjacent pond or well. In addition, fertilizing has been observed to reduce ammonia by increasing phytoplankton growth and activity, resulting in ammonia absorption. High nitrite concentrations can cause brown blood mia) in channel chloride
to nitrite
disease catfish ion
Severe
anemia
listed
in
in channel
ably have
exist. included
water
Table
catfish
Treatment maintaining
to nitrite ratio feed, although
and/or often
1 refers commonly
a!., 1989) have severe anemia. etiologies prob-
recommendations a high chloride changing type of neither of these rec-
ommendations so!ves the problem. In catfish with “gas-in-gut” condition, the intestine was distended three to eight times the normal diameter (Table 1). In these cases, no infection or water qualityrelated talities
problem was were attributed
condition.
No
identified, so morto the “gas-in-gut”
treatment LITERATURE
the
F.
ratio
6:1
tiated sulfonamide
below
have poorer do not hatch
called “white-lip” or “no-blood” disease. Hematocnits are often as low as 1 to 9% (Plumb et a!., 1986). Contaminated feed (Butterworth et al., 1986) and high nitrite
(methemoglobineespecially when falls
water At hard-
hatchery
‘
in the water (Tucker et been implicated in causing However, other unknown
catfish
in against
sometimes becoming enlarged and due to insufficient level of calcium water. The deficiency can be corby adding a calcium chloride
opaque in the rected
ditions.
pond-raised
in the
nitrite ions entering fish through the gills. Catfish farmers in the Mississippi Delta strive to maintain at least a 6 to 1 chloride to nitrite ratio, and frequently keep at least
to a condition
However,
ox-
to organs, thus suffocating fish in of adequate dissolved oxygen in the Adding salt (NaC1) to ponds elechloride concentrations and reduces
(approximately 48 hr of pumping with a re-lift pump into an 8 ha pond). Ammonia occurs in catfish ponds frequently at levels that are considered adverse or even lethal under laboratory conbecome acclimated to high ammonia, and diagnostic laboratories usually implicate ammonia as a disease-causing agent only when the concentration of the un-ionized
Nitrite
methemag!obin of oxygen
BOWSER,
P. STILES,
H.,
A.
D.
AND
has
H.
FRANCIS-FLOYD,
of
Edwardsiella
MAESTRONE.
therapy
found.
CITED
MUNSON,
G.
been
1986.
Poten-
ic-
SHORT
taluri
infection
in channel
ricultural
and
Research
Report.
Mississippi
catfish.
Forestry Mississippi
State,
Mississippi
Experiment State
Mississippi
Ag-
Station
M. W., R. M. DURBOROW, M. D. CROSBY, P. W. TAYLOR. 1989. Status of fish farming in Mississippi-April 1989. In For fish farmers, Extension
Service.
Mis-
sissippi sissippi
State University, Mississippi State, Mis1, 10 pp. BUTFERWORTH, C. E. , JR., J. A. PLUMB, AND J. M. GRIZZLE. 1986. Abnormal folate metabolism in feed-related anemia of cultured channel catfish. Proceedings
of the
Society
for
Experimental
Bi-
ology
and Medicine 181: 49-58. CROSBY, M. D. , AND R. M. DURBOROW. 1988. Channel catfish virus. Mississippi Cooperative Extension Service Information Sheet 1383, Mississippi State University, Mississippi State, Mississippi, 2 pp. G. E. , M. L. KENT, N. 0. DYBDAL, AND H. P. HEDRICK. 1986. Henneguya exilis Kudo associated with granulomatous branchitis of channel catfish Ictalurus punctatus (Rafin-
DUHAMEL,
esque).
Veterinary
Pathology
23:
354-361.
H. M. 1988. Ammonia in fish ponds. Mississippi Cooperative Extension Service Information Sheet 1333, Mississippi State University, Mississippi State, Mississippi, 2 pp. AND M. D. CROSBY. 1989. Brown blood
DURBOROW,
disease. vice
Mississippi
Information
Cooperative Sheet
1390,
Extension Mississippi
of
to increase
water
1989.
Use
hardness
of calcium in catfish
SerState
Sphaerospores
observed
in the
kidney
of
Systematic
8: 389-392.
1973.
of
Effects
fingerling
of temperature channel
on
1978.
.
disease.
Epizootiology Marine
, S. A. HOROWITZ, Feed-related anemia (Ictalurus punctatus).
MAESTRONE,
W.
cipal
A.
(ed).
225,
Station,
Auburn E.
B.,
40:
virus
26-29.
W. A. ROGERS. in cultured channel
AND
Aquaculture
B. sulfonamide
51:
Protozoan
1986.
catfish 175-179. 1987.
QUINLAN.
to control
infection in Aquaculture
of farm
Southern
Number SHOTTS,
1985.
diseases
catfish
Review
AND
Use of a potentiated wardsiella ictaluri (Ictalurus punctatus). ROGERS,
of channel
Fisheries
channel 62:
Ed-
catfish 187-194.
In Prin-
parasites.
raised
mor-
(Ictalurus with chanResearch
catfish
punctatus) experimentally infected nel catfish virus. Journal of Fisheries Board of Canada 30: 568-570.
G.
of
Journal
31 : 396-400. T. MCDOWELL,
Diseases
J. A.
chloride hatcheries.
International
, AND J. M. GROFF. Sphaerospora ictaluri n. sp. (Myxosporea: Sphaerosporidae) observed in the kidney of channel catfish, Ictalurus punctatus Rafinesque. Abstract in Fish health workshop. American Fisheries Society, Annapolis, Maryland, p. 21. JARBOE, H. H. , P. H. BOWSER, AND H. H. ROBINETTE. 1984. Pathology associated with a natural Edwardsiella ictaluri infection in channel catfish (Ictalurus punctatus Rafinesque). Journal of Wildlife Diseases 20: 352-354. MACMILLAN, J. H. 1985. Infectious diseases. In Channel catfish culture, C. S. Tucker (ed). Elsevier, New York, New York, pp. 405-496. MIYAZAKI, T. , AND J. A. PLUMB. 1985. Histopathology of Edwardsiella ictaluri in channel catfish, Ictalurus punctatus (Rafinesque). Journal of
tality
Mississippi Cooperative Extension Service Information Sheet 1388, Mississippi State University, Mississippi State, Mississippi, 2 pp. FRANCIS-FLOYD, H., M. H. BELEAU, P. WATERSTRAT, AND P. R. BOWSER. 1987. Effect of temperature on the clinical outcome of infection with Edward.siella ictaluri in channel catfish. Journal of the American Veterinary Medical Association 191: 1413-1416. FREUND, J. D., R. M. DURBOROW, J. H. MACMILLAN, M. D. CROSBY, T. L. WELLBORN, P. W. TAYLOR, AND T. E. SCHWEDLER. 1990. Utilizing diagnostic laboratory records to monitor the occurrence of entenic septicemia of channel catfish in Mississippi. Journal of Aquatic Animal Health. In press. GROFF, J. M., T. MCDOWELL, AND H. P. HEDRICK. 1989.
FHS/AFS
1989.
Fish
Mississippi State, Mississippi, 2 pp. . 1988. Monitoring winter kill conditions can cut losses. The Catfish Journal December 1988: 9. ,T. L. WELLBORN, JR., P. W. TAYLOR, AND CROSBY.
catfish.
Bacteriology HEDRICK, H. P.
AND
D.
punctatus).
5.
J. P. 1979. A bacterium associated with disease of pond cultured channel catfish, Ictalurus punctatus. Journal of the Fisheries Hesearch Board of Canada 36: 1508-1512. ‘ A. C. MCWHORTER, A. G. STEIGNERWALT, AND D. J. BRENNER. 1981. Edwardsiella ictaluri sp. ; the causative agent of entenic septicemia
PLUMB,
University,
M.
(Ictalurus
17:
147
HAWKE,
University,
1 1, 3 pp.
AND
Cooperative
catfish
Newsletter
BRUNSON,
Mississippi
channel
COMMUNICATIONS
J. A. Plumb
catfish,
Cooperative Services Bulletin Alabama Agricultural Experiment University,
V. S. BLAZER,
Alabama, AND
W.
pp.
D.
24-32.
WALTMAN.
1986. Pathogenesis of experimental Edwardsiella ictaluri infections in channel catfish (Ictalurus punctatus). Canadian Journal of Fisheries and Aquatic Sciences 43: 36-42. TUCKER, C. S., H. FRANCIS-FLOYD, AND M. H. BE1989.
LEAU.
Nitrite-induced
anemia
catfish, Ictalurus punctatus Rafinesque. letin of Environmental Contamination icology 43: 295-301. Received
for
publication
12 January
1990.
in channel
The Buland Tox-
