Aquatic parasites, bacteria, fungi Flashcards
What causes Marine Ich?
Cryptocaryon Irritans, a ciliate parasite
“White Spot Disease”
What causes Ich in Freshwater fish?
Ichthyophthirius multifilis, a ciliate parasite
How to diagnose Marine or Freshwater Ich?
Skin scrape
shows ciliates with visible macronucleus
What causes Velvet disease?
Amlyloodinium spp (marine fish)
Oodinium in fresh water fish
(a dinoflagellate parasite)
How do you treat Velvet disease in fish?
- Bath treatments with saline
What causes hole in head disease?
Hexamita spp.
CS of Hexamita in fish?
- 1st CS is slimy, white mucousy feces even when eating and acting normal
- Hiding in corner
- Swimming backwards
- Head above eyes gets thin
- Gets blackened in color
“Hole in Head disease”
How to treat Hexamita in fish?
- Metronidazole
(Hole in Head disease)
What causes whirling disease in fish?
Myxobolus cerebralis
What fish are most susceptible to Whirling disease?
- juvenile Salmonids, specifically Rainbow Trout in both farmed and wild populations
CS of whirling disease in fish?
- Erratic tail chasing
- Blackened caudal area
- Lifelong skeletal abnormalities, targets SC + CNS
What causes proliferative kidney dz in fish?
Tetracapsuloides bryosalmonae
one of the most serious parasitic diseases in salmonid populations, responsible for collapse of Arctic Char
How to diagnose Kudoa spp. in fish?
Sample predilection tissue, typically found in skeletal muscle but can be found anywhere
What causes post mortem myoliquification in fish?
Kudoa spp (Myxosporeans)
food safety concern, ass. w raw fish (tuna, amberjack)
What CS can be seen in fish infected with Kudoa spp.?
- White cysts in muscle
- Post mortem myoliquification
SLICE is an avermection parasiticide for treatment of?
Salmon louse
resistance has already been reported…
What fish parasite has a direct lifecycle?
Class Monogenea
(Looks like a fluke/trematode but in a different class)
How to treat Monogenea ectoparasites in fish?
- Skin flukes
- Tx with Praziquantel or H2O2 baths
List most IMPT things to know about Class Monogenea in fish?
- Direct life cycle
- Attach via hooks
- Tx with Praziquantel or H2O2 baths
What causes saddleback disease in fish and how does it appear?
- Caused by Flavobacterium columnare
- Moldy, cottony appearance, often mistaken for a fungal infection
- Gray patches on the body of fish
- Affects aquarium/pet fish
- Ass with shipping, warmer temps, poor water quality
What bacteria causes a moldy, cottony appearance on the body of aquarium fish?
- Flavobacterium columnare (Saddleback Disease)
What CS can be seen with Tenacibaculosis/Flavobacteriosis in farmed marine fish?
- Ulcers, necrotic lesions, and corrosion of the tail and fins
What can be a consequence of bacterial or parasitic infections causing a fish to have a pinecone like appearance?
Dropsy/Bloat
How to treat Francisellosis in farmed fish?
- Oxytetracycline
What causes furunculosis in fish?
Aeromonas salmonicida
Note: Aeromonas hydrophila causes motile aeromonas septicemia.. different than furunculosis
What is the difference between Aeromonas salmonicida and Aeromonas hydrophila?
- A. salmonicida is NON motile and causes furunculosis
- A. hydrophila is MOTILE
What causes raised muscle lesions resembling skil boils in fish?
Furunculosis / Aeromonas salmonicida
What can cause a C or S shaped body posturing in both marine or freshwater fish?
Streptococcus
(iniae or agalactiae)
What fish are resistant to Streptococcus?
Goldfish, Carp, channel catfish
What are risk factors for streptococcus infection in fish?
- High stocking density
- Poor water quality
- Warmer water temperatures
What vaccines are available for prevention of bacterial infections?
- Furunculosis (Aeromonas salmonicida)
- Streptococcus
- Vibrio (Red pest of eels/Hemorrhagic syndrome/Hitra dz)
What CS can be seen with Vibriosis?
- Red spots, swollen, dark lesions on skin that bleed
- Internal hemorrhage
- White/Grey lesions on intestines and spleen
What causes bacterial kidney dz in fish?
Renibacterium salmoninarium
REPORTABLE!!, no treatment
What is phaeohyphomycosis caused by?
Exophilia spp. (dematiaceous fungi)
“Black yeast”
What disease targets fish eggs and juvenile fish in hatcheries?
Saprolegniasis (water mold, not a fungus)
What fish species are most affected by Saprolegniasis (water mold, not a fungus)?
fish eggs and juvenile fish in hatcheries
What causes gill rot and what species are affected?
- Branchiomycosis (water mold, not a fungus)
- Ornamental and freshwater koi, eel, bass, perch affected
CS of Branchiomycosis?
- Gill rot
- Acute infection of gills with high mortality
- Respiratory distress
- Patchy, marbled appearance of gills
(Water mold, not a fungi)
Risk factors for Branchiomycosis / Gill rot?
- Low pH
- Low DO2
- Overcrowding
- High algal bloom
Causative agent of cotton shrimp disease?
Microsporidiosis
What causes xenomas in fish?
Microsporidiosis “Cotton Shrimp Disease”
CS of Cotton shrimp disease?
- Xenomas (single hypertrophied cell containing millions of spores)
- Infections are chronic, spores persist for years in tanks and ponds
List IMPT facts about Spring Viremia of Carp
- Infectious swim bladder inflammation
- NOTIFIABLE DISEASE
- Causative agent: Rhabdovirus
- Kidney, Spleen, Liver affected
- Loss of water balance
- Impairment of immune response
What species of fish is affected by infectious swim bladder inflammation?
Carp - Spring Viremia of Carp
NOTIFIABLE DISEASE
What fish species is affected by Herpesvirus-3?
KOI
What fish species is resistant to Herpesvirus-3 infection?
Goldfish are unaffected
Disease of Koi /Cyprinids!
What diseases are goldfish unaffected by?
- Koi / Cyprinid Herpesvirus-3
- Streptococcus
CS of Koi Herpesvirus-3?
- Red and white patches on gills
- Sunken eyes
- Acute mortality
CS of infectious salmon anemia virus?
- Widespread hemorrhage
- Anemia, pale heart and gills
- Gasping at the surface
REPORTABLE/NOTIFIABLE TO WOAH, Tx is by killing all fish in the tank, must eradicate
What emerging disease in salmon predisposes to gas bubble disease?
Salmon Gill Poxvirus
CS of Salmon Gill poxvirus?
- Respiratory distress
- Gas bubble disease
- Gasping at surface
- Increased operculum movement
List Reportable viral diseases to WOAH
- Infectious Salmon Anemia virus
- Spring Viremia of Carp
- Viral hemorrhagic septicemia
- Infectious haematopoetic necrosis virus
- Salmon Alpha virus (Pancrease dz)
Risk factor for Salmon gillpox virus?
Increased DO2 / Supersaturation of nitrogen or O2
(Gas bubble disease)
