PROPOSED IHNV BROODSTOCK SAMPLING PROGRAM FOR IDFG STEELHEAD DOUG MUNSON And DR. PHIL MAMER LSRCP MEETING 2012

CONVERSATIONS WITH EXPERTS MOVE EGGS NOT FISH…SCOTT LAPATRA IF YOU HAVE IHN, YOU HAVE A BIO-SECURITY PROBLEM…SCOTT LAPATRA AND GAEL KURATH TO DATE THERE IS NO EVIDENCE OF VERTICAL TRANSMISSION OF IHN, THE PROBLEM IS YOU CANNOT PROVE A NEGATIVE…SCOTT AND GAEL

SUSCEPTABLE SPECIES (to natural infection) All Pacific Salmon (Sockeye, Chinook, Coho, Pink, Chum, (Masu & Amago) Steelhead/rainbow trout Atlantic salmon Brook trout* Brown trout* Cutthroat trout* *More resistant to clinical disease

“U” clade Sockeye Salmon “M” clade Steelhead/Rainbow “L” clade Chinook Salmon

INFECTIOUS HEMATOPOIETIC NECROSIS VIRUS (IHNV) Native to salmonids in NW North America. Rhabdovirus (bullet- shaped, ssRNA). Attacks the hematopoietic tissues of the kidney. Transmission fish-to- fish and via egg surface contamination.

TRANSMISSION CLINICALLY INFECTED AND COVERT CARRIERS – CULTURED, FERAL, AND WILD VIRUS IS SHED – URINE, OVARIAN FLUIDS, EXTERNAL MUCUS – KIDNEY, SPLEEN, OTHER INTERNAL ORGANS – GILL AND BRAIN VECTORS – INSECTS, ANNELIDS, CRUSTACEANS – WATER DROPLETS (FOMITE) AND EQUIPMENT CLINICAL OUTBREAKS AT 10⁰C – NOT NATURALLY ABOVE 15⁰C

Lethargy Darkened color Pop-eye (exophthalmia; often with hemorrhage)  Anemia (loss of red color in gills and internal organs)  Spleen normal size  Mortality rate often exponential CLINICAL SIGNS OF IHN

DIAGNOSTIC TOOLS

PCR CONFIRMATION

Management for IHN Avoidance – Broodstock sampling Test all parent females at spawning and cull eggs from positive individuals. – Egg disinfection Iodophor is an effective surface disinfectant for both water hardening and eyed stages. – Isolation/Quarantine A pathogen-free water source is critical! Do not bring a source onto your hatchery.

Management for IHN Successful example: – Clearwater Hatchery: test 100% brood, disinfect, and quarantine. – Water source without anadromous fish. Moderate success: – Niagara Springs Hatchery: test and disinfect, but isolation is not always complete. – IHN outbreaks usually in fry shipments.

Culture Opportunities Bio-Security/Integrated Fish Health Management Disease free water supply Disinfection and quarantine Compartmentalization: spread the risk within and between facilities Hatchery personnel charged with decision to destroy infected groups

CLEARWATER STEELHEAD RECEIVE ONLY EGGS FROM IHN NEGATIVE FEMALES IODOPHOR GREEN EGGS AT SPAWNING IODOPHOR EGGS UPON ARRIVAL AT CLEARWATER TO DATE, NO DETECTIONS OF IHN IN JUVENILE STEELHEAD

BIO-SECURITY BROODSTOCK TESTING IODOPHOR DISINFECTION OF EGGS – ADDITIONAL DISINFECTION IF EGGS ARE MOVED TRANSPORT EGGS CERTIFICATION TESTING BEFORE TRANSPORT OF FISH – Phase out DISINFECTION OF EQUIPMENT AND RACEWAYS – FOOT BATHS AND HAND SANITIZER PERIODIC JUVENILE INSPECTION BIO-SECURITY AUDITS

PREDICTIONS Virus will become widely established in the basin Additional host species will become involved Virus will persist in low-level carriers much of the year Stressors will exacerbate latent infections and disease Disease will occur on periodic basis – especially in the spring Recovered fish will become immune, leading to disease occurring primarily in younger age classes Disease will have population-level effects for some species Disease will become less explosive in most years Disease will impact both management and commercial activities It will be important to prevent the spread of the virus to other freshwater systems in the U.S. and Canada, as well as to the commercial aquaculture industry

CONCLUSIONS APPLY CLEARWATER PLAN THOUGHOUT IDFG – MORE FISH TO SAMPLE AND SPAWN – MORE HOURS SPAWNING, SAMPLING, PROCESSING – MORE $ (INCREASE COST OF DOING BUSINESS) MOVE EGGS – CAN DISINFECT EGGS – CANNOT DISINFECT FISH MAINTAIN HIGH LEVEL BIO-SECURITY

MORE HEALTHY FISH TO RELEASE MORE HEALTHY FISH RETURNING SO MANY, EVEN TRAVIS WILL BE SUCCESSFUL NO EXOTIC IHNV TYPES INTO HAGERMAN VALLEY