Exotics Top Topics - Reportable Aquatic Diseases Flashcards
what government entity is the main regulator of aquaculture in the united states? what is responsible for global monitoring of reportable diseases?
USA - USDA-APHIS
globally - world organization for animal health (OIE)
how many aquatic questions should you count on for the NAVLE?
3 that matter
T/F: most of the reportable aquatic diseases have a temperature range & susceptible species that can be used to rule in or rule out any differentials
true
what 6 fish diseases are of regulatory concern in both the USA & canada?
- viral hemorrhagic septicemia
- infectious hematopoietic necrosis
- spring viremia of carp
- epizootic hematopoietic necrosis
- infectious salmon anemia
- koi herpes virus
what is the classic case presentation of viral hemorrhagic septicemia? what species is it endemic in?
acute hemorrhaging, exophthalmia, ascites, & neuro form with spinning
endemic in salmonids, haddock, & cod in PNW & emerging in great lakes region
what is the classic case presentation of infectious hematopoietic necrosis? what species is it endemic in?
lethargy with sporadic bouts of rapid swimming, ascites, protruding vent, fecal casts, & high mortality in fish under 1 year of age
endemic - salmonids in the PNW & alaska & also seen in europe, asia, & western us
what is the classic case presentation of spring viremia of carp? what species is it endemic in?
also occurs in aquarium fish, koi, & goldfish - nonspecific signs but may appear similar to a motile aeromonad infection
not in the US since 2007 - seen in china, middle east, eastern europe, & russia
what is the classic case presentation of epizootic hematopoietic necrosis? what species is it endemic in?
acutely high death rates, hemorrhage around nares, ataxia in redfin perch > rainbow trout
what is the classic case presentation of infectious salmon anemia? what species is it endemic in?
severe anemia, petechiae, ascites
endemic - northeastern US, atlantic canada, norway, & scotland
what is the classic case presentation of koi herpes virus? what species is it endemic in?
aquarium fish & koi, goldfish can also be infected but don’t get sick (asymptomatic carriers) - severe patchy gill necrosis, rapid mortalities
sporadic throughout the US in carp & hybrids
what 6 fish diseases are reportable in the US only?
- red sea bream iridoviral disease
- salmonid alphavirus
- epizootic ulcerative syndrome
- gyrodactylus salaris infection
- tilapia lake virus
- strains of virulent aeromonas hydrophilia of farmed channel catfish
what is the classic case presentation of red sea bream iridoviral disease? where is it seen/endemic in?
severe lethargy, anemia in red sea bream
what is the classic case presentation of salmonid alphavirus? where is it seen/endemic in?
pancreas disease or sleeping disease - at necropsy, see necrosis of the heart, skeletal muscles, & exocrine pancreas
not seen in the US - seen in europe
what is the classic case presentation of epizootic ulcerative syndrome? where is it seen/endemic in?
mycotic granulomatosis - also seen in aquarium fish - caused by the oomycete aphanomyces invadens (water mold) - deep ulcers with granulomatous reactions
sporadic thoughout US & worldwide
what is the classic case presentation of gyrodactylus salaris infection? where is it seen/endemic in?
external parasite that causes huge losses in naive trout & salmon
not seen in US - seen in finland, russia, & a big problem in UK & ireland
what is the classic case presentation of tilapia lake virus? where is it seen/endemic in?
non-specific signs of lethargy, loss of appetite, decreased schooling behavior, popeye (exophthalmia), darkening ulcers, & hemorrhages
seen in US, asia, africa, central america, & south america
what is the classic case presentation of strains of virulent aeromonas hydrophilia of farmed channel catfish? where is it seen/endemic in?
strain ST251 - phylogenetic differences in between ST251 strains of vAh (hypervirulent Ah) & non-virulent a. hydrophila (non-Ah)
disease caused by vAh is similar to that caused by non-vAh - but differences in disease epidemiology, pathogenesis, & presentation
currently identified in 3 states (arkansas, alabama, & mississippi) & 6 chinese provinces
what is the classic case presentation of infectious pancreatic necrosis? where is it seen/endemic in?
skin darkening, swimming in a corkscrew pattern, ataxia, anorexia, & exophthalmia
seen worldwide except for australia & iceland
what is the classic case presentation of ceratomyxosis? where is it seen/endemic in?
slow swimming, anorexia, darkening, ascites, erythematous, protruding vent, & exophthalmia
seen in british columbia
what is the classic case presentation of whirling disease? where is it seen/endemic in?
fish chase their tails/whirl when startled, skeletal deformities, & darkening of tails/peduncle
seen in US, canada, europe, & south america
what is the classic case presentation of white sturgeon iridoviral disease? where is it seen/endemic in?
anorexia, weight loss, erratic swimming, erythema of the belly, swollen pale gills, & death
what is the only USDA APHIS reportable monogenean in the US? what is the classic case presentation?
monogenean infections in fish from gyrodactylis salaris salmonid specific monogenean
what is the etiology of monogenean infections in fish? how is it diagnosed?
gyrodactylis salaris salmonid specific monogenean
skin scrape or fin & gill biopsy with ID of parasite based on morphology/movement
how are monogenean infections in fish treated?
commonly managed by bath/immersion treatment & attention to environmental cleaning, species tolerance, & legal/environmental considerations
formalin, fda approved products, praziquantel, organophosphates, & hydrogen peroxide
freshwater dips for marine species or long-term immersion for euryhaline species
saltwater dips for freshwater species
how does treatment differ for gyrodactylids causing monogenean infections in fish?
live-bearing, so killing adults kills juveniles & one treatment should work but may need additional treatment for microenvironments
how does treatment differ for dactylogyrids, ancyrocephalids, & capsilids causing monogenean infections in fish?
they are egg layers - focus on environmental management (eggs) so multiple treatments are required to kill emergent, susceptible juvenile stages
what is important for reducing the impact/introduction of monogenean infections in fish?
good screening/quarantine/biosecurity practices
what 4 fish diseases are reportable in the US only?
- infectious pancreatic necrosis
- ceratomyxosis (ceratomyxa shasta)
- whirling disease - myxobolus cerebralis
- white sturgeon iridoviral disease
what is the lifecycle of monogeneans that cause infections in fish?
direct life cycle (unlike related digenea which requires at least 2 live hosts)
