Infectious Hemapoietic Necrosis

(IPN)

Viral disease of trout & salmon. Survivors are often carriers of the infection.

Symptoms:  1) lethargic

2) display of sporadic whirling or other abnormal swimming activity

3) abdominal swelling

4) exopthalmia

5) pale gills, fin hemorrhaging, dark body coloration.

6) Internal examination reveals pale liver, spleen, & kidneys.

Treatment: No known cure for fish, but eggs may be treated.

Sometimes these are problems in fish culture situations. In carps there are 3 that are of Asian origin (Bothriocephalus opsarchthydis. B. aicheilograthi, & B. gowkongensis). These can cause intestinal blockage, and eventually the fish starve to death. In black bass, Proteocephalus ambioplites can be a problem.

Symptoms: 1) intestinal blockage

2) starvation

Diphllobothrium latum

Brood Fish Tapeworm

(walleye & bass)

Treatment: w/ a food additive known as di-N-butyl tin oxide

Ectoparasites on gills & body of fishes. They feed on body fluids of fish. Eragsilus parasitizes the gills of fish & can lead to respiratory impairment, reduced growth, and mortality. Argulus & Lernea attach to the body surfaces of fishes & can lead to mortality of small fishes. Treatment is with Dylox. (crusteaseans- "sealice" & "fish tick"- Argulus- anchor worms!)

Lesions/wounds can lead to secondary infections

Symptoms:

1)shallow ulcers that are reddish or grayish in color.

2) inflamation of tissues surrounding the mouth.

3) exopthalmia

4) abdominal distention

5) bloody or opaque fluid in the intestine

Treatment: Terramycin added 2 food -or-

furacin (yellow powder put in the water) <- illegal

Symptoms:

1) Black spot (Neascus, Uvulifer) found in the epidermal & muscle tissue.

2) White grub (Posthodiplostomum minimum) found in the liver & heart.

3) yellow grub (Clinostomum marginatum) often found in the muscle tissues.

Treatment: By control of snail populations

Symptoms:

1) body discoloration

2) shallow ulcerations

3) gills may have eroded filaments & lamellae

Note: secondary infection takes advantage of abrassions caused by spawning

Treatment: furacin or diquat added to the water

(economical but not approved)

Symptoms: none.

Affects the kidneys

Treatment: Erythromycin

Viral Hemmorrhagic Septicemia

(VHS)

Symptoms: Infected fish...

1) are lethargic

2) avoid water currents

3) seek edge of holding facility

4) Fish body becomes darker w/ progession of the disease

5) As fish become older, they become more resistant to the disease

Treatment: No known treatment for fish.

Eggs can be treated with Wescodyne.

Icthyopthirius multifilis

("ICH")

Symptoms: fish "itch" & flash

1) thickening of epithelia & excessive mucous

2) infected fish congregate around flowing water & have small white pustules on their bodies

Treatment: Formalin & Malachite green<- illegal!cargenogen.

Only 2 treatable stages: tomite (infects the fish) & tomalite (free-swimming stages)

if the stage encysts, it's protected

Treatment is effective when the pustules completely dissappear

Symptoms:

1) White cottony growths on infected fish or on egg masses.

Treatment: Eggs: malachite green

Fish: can be treated with formalin

Both: hydrogen peroxide

Symptoms: Not specific, therefore, to diagnose the bacteria must be isolated. Usually mimmicks furunculosis, but without the lesions.

Treatment: Sulfurmerazine (very potent!)

Symptoms

1) irregular white blotches on head & dorsal surface of fishes (body, fins, or gills)

2) fraying of fins, loss of appetite, or excess mucous production. * dorsal fin is the fav. spot!

Treatment: salt (NaCl)

acetic acid

formalin

hydrogen peroxide

Symptoms:

1) grayish- white or blue cast on the fish

2) excessive mucous production & necrosis of epidermal tissue.

3) rapid mortality may result

4) attacks gills and external body surface

Treatment:

acetic acid

-or-

formalin dip treatments

Symptoms:

1) white cysts on the skin, barbels, or gills (look like tumors)

Treatment: spores are resistant to treatment

Symptoms:

1) fish swim near the water surface with their head down & tails protruding above the surface

2) Fish swim at the surface with the backs exposed

3) Fish swim erractically on their sides

4) Fish swim upside down with the swim bladder distended.

Treatment:
Driving off excess gas from the water by aeration or agitation

Channel Catfish Virus

(CCV)

Symptoms:

1) Fluid in abdominal cavity

2) exopthalmia

3) anemia

4) hemorrhaging of gills, fins, skin, kidneys

5) absence of food in the intestine due to lack of feeding

Treatment: No known cure

Symptoms:

1) found on gills, body, fins of freshwater fishes

2) gill flukes (ex. gyro)

Treatment: formalin & hydrogen peroxide

Viral Hemorrhagic Septicemia

(VHS)

Icthyopthirius multifilis

(ICH)

Channel Catfish Virus

(CCV)