Did put in any wild-(lake) caught freshwater fish in your tank? I hope you don't have the "VIRUS" form of it:
Millions of hatchery-raised salmon and trout have been saved from possible destruction because DNA probes developed by USGS biologists can now be used to distinguish between European and North American strains of a highly feared fish disease agent, viral hemorrhagic septicemia virus (VHSV).
During a severe epizootic among the snakehead fish, Ophicephalus striatus, in Thailand, a virus belonging to the Rhabodviridae was isolated in cell culture. The virus was bacilliform 60-70 nm in width and 180-200 nm. in length and was surrounded by a lipid envelope. The virus replicated optimally at 24-30 0C in snakehead fin and carp cell lines. Exponential growth on Epithelioma papulosum cyprini (EPC) cells at 270C began after a 4 h latent period and continued during the next 6 h. After 14 h of incubation, all of the cell-associated virus had been released. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed five virion structural proteins, the L,G,N,M1, and M2 similar to those of the salmonid rhabdoviruses, infectious hematopoietic necrosis virus and viral hemorrhagic septicemia virus. The estimated molecular weights of the five snakehead rhabdovirus polypeptides were > 150, 69, 48.5, 26.5, and 20 Kilodaltons (Kd.). The 69 Kd Molecular weight protein was glycosylated. The virus has been named the snakehead rhabdovirus. While the virus characterized in this report was isolated from diseased fish, there is no data indicating it is the cause fo the disease.
(Bacteria is easier to deal with) Try
another antibiotic like Tetracycline etc..
B
Bacterial Disease
1) Aeromonas hydrophila (Bacterial Hemorrhagic Septicemia)
A) Gram negative motile rods
B) Effects many freshwater species and usually is associated
with stress and overcrowding.
C) The clinical signs and lesions are variable.
The most common finding is hemorrhage in skin, fins,
oral cavity and muscles with superficial ulceration of
the epidermis. Occasionally cavitary ulcers (similar to
A. salmonicida) are observed. Exophthalmus is
occasionally observed.
D) Diagnosis is rendered by culturing the organism from affected
animals: Remember this is a common water saprophyte with a
great variation in virulence in serotypes.
E) Disease is transmitted via contaminated water or diseased
fish.
2) Pseudomonas fluorescens
A) Gram negative rod
B) Lesions similar to Aeromonas hydrophila
3) Vibrio
A) Gram negative rod, lives primarily in a marine environment
B) Vibrio septicemia: V. alginolyticus / V. anquillarum
Septicemia has similar lesions to Aeromonas hydrophila.
c) Ulcer Disease of Damselfish: V. damsela
a. Deep skin ulcers and necrotizing myositis.
b. Lesions similar to Aeromonas salmonicida.
4) Edwardsiella tarda (Edwardsiella septicemia)
A) Gram negative motile rod
B) The disease affects primarily channel catfish but also
observed in goldfish, golden shiners, largemouth bass, and
the brown bullhead. This organism is the most serious
disease involving the eel culture of Asia.
C) The lesions are similar to A. hydrophila with small cutaneous
ulcers and hemorrhage observed both in the skin and muscle.
Muscle lesions often develop into large gas filled
(malodorous) cavities. Diseased fish lose control over the
posterior half of their body yet continue to feed.
5) Edwardsiella ictaluri (Enteric septicemia of catfish)
A. Gram negative rod
B. Disease affects primarily fingerlings and yearling catfish
C. Clinical signs of enteric septicemia of catfish closely
resembles those of other systemic bacterial infections. The
most characteristic external lesion is the presence of a
raised or open ulcer on the frontal bone of the skull between
the eyes (Hole in the head disease).
6) Aeromonas salmonicida (Furunculosis, Ulcerative disease of goldfish)
A. Gram negative rod
B. This bacteria affects primarily salmonids but other
freshwater fish can be affected.
C. Clinically the disease may be demonstrated as a septicemia
with hemorrhage in the muscles and other sites. The major
lesion is a subcutaneous swelling that often causes an
ulcerative dermatitis. These lesions may cavitate into the
adjacent musculature. Histologically there is necrosis of
the affected tissue with abundant colonies of bacteria and
few inflammatory cells due to the bacteria's leukocytolytic
exotoxin.
D. The disease is transmitted by contact with diseased fish,
contaminated water, fomites, and infected eggs.
7) Yersinia ruckeri (Enteric red-mouth)
A. Gram-negative motile rod
B. The bacteria affects salmonids; rainbow trout are the most
susceptible.
C. Clinically this disease manifest itself as a septicemia with
hemorrhage and ulceration of the jaw, palate, and operculum.
Histologically numerous bacterial colonies admixed with
inflammatory cells are observed in many areas of necrosis
involving the liver, spleen and kidney.
D. The disease is transmitted by contact with diseased or
carrier fish, and contaminated water.
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Joe
www.cichlidfish.com