Aquaculture improving?..The Fish Farm Thread

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Infectious agent detections in archived Sockeye salmon (Oncorhynchus nerka ) samples from British Columbia, Canada (1985-94)

Articlein Journal of Fish Diseases 2019(1):1-15 · February 2019with 102 Reads 
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The article can be found at:
https://onlinelibrary.wiley.com/doi/10.1111/jfd.12951

and it should be noted that they did NOT test for ISAv nor would I expect them to find PRv in archived samples. Remember the longitudinal study - and how it showed that the fish host was clear of the virus by the time that HMSI lesions were noticed? Which is why DFO & the industry denied PRv was causing HMSI for so long - even tho they were yet again wrong? These samples were preserved AFTER HMSI appeared would be expected to be clear of PRv by then.

nice try...
 
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Never mentioned prv did I but the conclusion r the same only for the last 10 years have they been able to test for PRV and according to peer reviewed science done on samples it appears it was here before the industry. Just because you don’t like the peer review science does not make it untrue.

Molecular testing of archived fish tissues in BC has shown that PRV was present in wild and farmed salmonids since 1987 and may have been present as early as 1977 in one sample from steelhead trout (19)


The ENGO pundits would lead people to believe, That all these virus are here as a result of fish farms but again the latest PEER REVIEWED SCIENCE IS SAYING THAT'S NOT TRUE. its okay tho, there distractions and miss truths all see to be for donations. So remember to donate to them!

Infectious agent detections in archived Sockeye salmon (Oncorhynchus nerka ) samples from British Columbia, Canada (1985-94)

Articlein Journal of Fish Diseases2019(1):1-15 · February 2019with 102 Reads 

In response to concerns that novel infectious agents were introduced through the movement of eggs as Atlantic salmon aquaculture developed in British Columbia (BC), Canada, we estimated the prevalence of infectious agents in archived return‐migrating Sockeye salmon, from before and during aquaculture expansion in BC (1985–94). Of 45 infectious agents assessed through molecular assays in 652 samples, 23 (7 bacterial, 2 viral and 14 parasitic) were detected in liver tissue from six regions in BC. Prevalence ranged from 0.005 to 0.83 and varied significantly by region and year. Agent diversity ranged from 0 to 12 per fish (median 4), with the lowest diversity observed in fish from the Trans‐Boundary and Central Coast regions. Agents known to be endemic in Sockeye salmon in BC, including Flavobacterium psychrophilum, Infectious haematopoietic necrosis virus, Ceratonova shasta and Parvicapsula minibicornis, were commonly observed. Others, such as Kudoa thyrsites and Piscirikettsia salmonis, were also detected.Surprisingly, infectious agents described only recently in BC salmon, Ca. Branchiomonas cysticola, Parvicapsula pseudobranchicola and Paranucleospora theridion, were also detected, indicating their potential presence prior to the expansion of the aquaculture industry. In general, our data suggest that agent distributions may not have substantially changed because of the salmonaquaculture industry.
 
Here's a important and telling quote from the study you quote above; Discussion, p.12:

" A previous study by Marty et al. (2015), which utilized archived formalin‐fixed and embedded material to detect the virus via qPCR, originally suggested that the virus may have been in BC since 1977; however, this was a weak detection (Ct 38.3). From Marty et al. (2015), the strongest support for PRV detection was in 1992 in Chinook salmon samples, the first (post‐1977) detection of PRV in duplicate assays and confirmed by sequencing. Furthermore, from 1992 onward, PRV was detected in duplicate samples, and at CT values of less than 35, some even <30.

We did not detect PRV in any of our archived Sockeye salmon samples, and while recent data (since 2005) from our laboratory have detected PRV in Sockeye salmon (e.g., Miller et al. (2014)), it was also detected in three of the post‐1992 archived samples of Sockeye salmon analysed by Marty et al. (2015). A recent study by Purcell et al. (2018) did not detect PRV in 394 samples of Sockeye salmon tested, while Morton, Routledge, Hrushowy, Kibenge, and Kibenge (2017)showed that the prevalence of PRV in Sockeye salmon, relative to other salmonid species, was particularly low (2.3%, n = 344). These studies suggest, in general, that prevalence of PRV is low in Sockeye salmon compared to Chinook or Coho salmon. Our data are limited because of the use of single tissue sample in adult salmon to infer, with any degree of confidence, either the presence or absence of PRV during our study period."
 
so when did the NORWEGIAN industry arrive in BC? early 1970s?

and the virus of NORWEGIAN origin was found in 1992?

and the most plausible origin of that virus is?
 
Our data are limited because of the use of single tissue sample in adult salmon to infer, with any degree of confidence, either the presence or absence of PRV during our study period."

Glade we can agree on that, jury is still out and that is what the PSF says.
 
so when did the NORWEGIAN industry arrive in BC? early 1970s?

and the virus of NORWEGIAN origin was found in 1992?

and the most plausible origin of that virus is?

The studies don’t call it Norwegian origin only you do and you claim it’s the most plausible.

Sounds more like engo propaganda then anything to do with science.
 
Here's another good one indicating that risk to wild salmonids:

Piscine orthoreovirus‐3 is prevalent in wild seatrout (Salmo trutta L.) in Norway
https://onlinelibrary.wiley.com/doi/10.1111/jfd.12943

and the most plausible origin of that virus is?

Seems like the most plausible is of it being from the Pacific ocean just like how transplanted trout spread IHNV to europe could they also of spread PVR.


“While European origin Atlantic salmon have been introduced to B.C. and Washington State, there has also been extensive transplantation of native Pacific salmon and trout eggs into Europe and elsewhere [19]. Transplanted rainbow trout contributed to the spread of infectious hematopoietic necrosis virus (IHNV), a salmonid virus endemic to western North America, to Europe and Asia [20, 21]. If PRV was endemic to western North America, it is equally probable that movement of infected Pacific salmon or trout eggs could have concomitantly spread PRV in Europe. There have been no published retrospective studies of archived samples conducted in Norway to determine how long the virus has been present in that country. However, Atlantic salmon tissues from Norway collected in 1988 tested positive for PRV RNA (Rimstad pers. comm.) suggesting that the virus was present at least a decade prior to the first reports of HSMI. There has been little surveillance for this virus outside Norway and Western North America. Thus, it is premature to speculate about transmission pathways given the lack of understanding of the global distribution of PRV.”
https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0141475
 
Doubt is certainly the most valuable commodity used as a weapon for defending the open net-pen industry. Thanks for illustrating that, WMY.

1992 is the date in question, WMY - not 1982. The reason the pro-lobby (Marine Harvest & the private lab - the authors) wants to roll back that date of 1992 to 1982 is to support the assertion they are proposing that it happened 1st here - then in Norway.

No conflicts of interest in that assertion (sarcasm)...
 
So when you agree with the "may" in peer reviewed science its "most plausible and fact"
When you disagree with the "may" in peer reviewed science its "doubt is the most valuable commodity"

Thanks for illustrating that...
 
Always amazes me how quickly FF pundits seem to forget things & so easily:

https://virologyj.biomedcentral.com/track/pdf/10.1186/1743-422X-10-230
"The Canadian PRV diverged from Norwegian sub-genotype Ia around 2007"

https://virologyj.biomedcentral.com/articles/10.1186/s12985-019-1148-2
"the PRV strains present in the escaped farmed Atlantic salmon were very similar to PRV in farmed Atlantic salmon in Iceland, the reported country of origin of the Atlantic salmon eggs used in commercial aquaculture in Washington State. This finding of Icelandic PRV in egg samples taken from the escapees in Washington State completes the infection cycle of PRV in farmed Atlantic salmon. It is also the first direct evidence of international movement of PRV via Atlantic salmon eggs."

other PRv- related articles:
https://www.psf.ca/sites/default/files/ISH Manuscript + Suppl mat.pdf
https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0188793
https://www.facetsjournal.com/doi/10.1139/facets-2018-0008
https://journals.plos.org/plosone/article/related?id=10.1371/journal.pone.0171471
 
It amazes me how quickly ENGO pundits seem to forget this so easily....Guess it must be that time of year for tax donations.

“While European origin Atlantic salmon have been introduced to B.C. and Washington State, there has also been extensive transplantation of native Pacific salmon and trout eggs into Europe and elsewhere [19]. Transplanted rainbow trout contributed to the spread of infectious hematopoietic necrosis virus (IHNV), a salmonid virus endemic to western North America, to Europe and Asia [20, 21]. If PRV was endemic to western North America, it is equally probable that movement of infected Pacific salmon or trout eggs could have concomitantly spread PRV in Europe. There have been no published retrospective studies of archived samples conducted in Norway to determine how long the virus has been present in that country. However, Atlantic salmon tissues from Norway collected in 1988 tested positive for PRV RNA (Rimstad pers. comm.) suggesting that the virus was present at least a decade prior to the first reports of HSMI. There has been little surveillance for this virus outside Norway and Western North America. Thus, it is premature to speculate about transmission pathways given the lack of understanding of the global distribution of PRV.”
https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0141475


Articlein Journal of Fish Diseases2019(1):1-15 · February 2019with 102 Reads 

In response to concerns that novel infectious agents were introduced through the movement of eggs as Atlantic salmon aquaculture developed in British Columbia (BC), Canada, we estimated the prevalence of infectious agents in archived return‐migrating Sockeye salmon, from before and during aquaculture expansion in BC (1985–94). Of 45 infectious agents assessed through molecular assays in 652 samples, 23 (7 bacterial, 2 viral and 14 parasitic) were detected in liver tissue from six regions in BC. Prevalence ranged from 0.005 to 0.83 and varied significantly by region and year. Agent diversity ranged from 0 to 12 per fish (median 4), with the lowest diversity observed in fish from the Trans‐Boundary and Central Coast regions. Agents known to be endemic in Sockeye salmon in BC, including Flavobacterium psychrophilum, Infectious haematopoietic necrosis virus, Ceratonova shasta and Parvicapsula minibicornis, were commonly observed. Others, such as Kudoa thyrsites and Piscirikettsia salmonis, were also detected.Surprisingly, infectious agents described only recently in BC salmon, Ca. Branchiomonas cysticola, Parvicapsula pseudobranchicola and Paranucleospora theridion, were also detected, indicating their potential presence prior to the expansion of the aquaculture industry. In general, our data suggest that agent distributions may not have substantially changed because of the salmonaquaculture industry.

https://www.dnr.wa.gov/sites/default/files/publications/PRV whitepaper revised Sept 2017.pdf?3c0h5&9laxp

Summary Conclusion Based on Available Data: The ubiquitous nature of piscine orthoreovirus (PRV), its apparent historic presence in wild Pacific salmonid stocks in the Pacific Northwest and the lack of clear association with disease in Pacific salmonids suggest the virus poses a low risk to wild species of Pacific salmonids.

Molecular testing of archived fish tissues in BC has shown that PRV was present in wild and farmed salmonids since 1987 and may have been present as early as 1977 in one sample from steelhead trout (19)

Why PRV in the PNW is of low risk regarding HSMI in wild Pacific Salmonids
1. The disease “heart and skeletal muscle inflammation” (HSMI) has not been reported in wild salmon populations in Norway or elsewhere and appears to only be a threat to farmed fish
2. While PRV causes HSMI in farmed Norwegian Atlantic salmon, high levels of PRV genetic material have been detected in asymptomatic wild and cultured salmonids with no evidence of HSMI disease
3. Histopathological lesions of HSMI were recently described as statistically correlated with the presence of PRV at one Atlantic salmon farm in British Columbia, Canada (BC) while other studies have detected the presence of PRV genetic material in wild and cultured Chinook, coho and pink salmon and steelhead trout from Washington State, BC and Alaska where years of surveillance have reported no presence of HSMI
4. Molecular testing of archived fish tissues in BC has shown that PRV was present in asymptomatic wild and farmed Pacific salmon since 1987 and may have been present as early as 1977 before Atlantic salmon were imported for aquaculture
5. HSMI has not been reported in Pacific salmon or steelhead in North America to date
6. Laboratory studies with Chinook and sockeye salmon have demonstrated that PRV is infectious and will persist for quite some time but does not cause fish mortality, HSMI, or any other apparent disease
7. Development of HSMI and HSMI-like diseases of farmed salmonids (Atlantic and coho salmon; rainbow trout) infected by PRV may be a result of different viral strains, host specific antiviral responses and environmental stressors that do not appear to be present or active for indigenous salmon on the Pacific Coast
8. The presence of PRV genetic material in Pacific salmon tissues is not sufficient evidence for HSMI disease

Laboratory challenges of Chinook, sockeye and Atlantic salmon injected with PRV infected material from Pacific Northwest salmonids resulted in no significant mortality or clinical disease (21, 22). A second study of Chinook salmon also injected with PRV positive material from Pacific Northwest salmonids resulted in virus replication with transient cytoplasmic inclusion bodies in red blood cells causing no reduction in hematocrits and no fish mortality (23). Similar challenge studies in rainbow trout (23) also resulted in no direct mortality following injection with PRV infectious material. These experimental studies suggest PRV in the Pacific Northwest is of low virulence for rainbow trout, Chinook and sockeye salmon.

The PRV strain present in indigenous Pacific salmon in the PNW, historically and experimentally, appears to be relatively benign and unable to produce significant disease or HSMI in native salmonids.
 
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outdated and erroneous grey literature & articles that still claim PRv doesn't cause HMSI - isn't the best way to build the credibility of the industry...
 
If ENGO pundits wish to dispute the claims perhaps they should take it up with the authors.

They seem pretty credible to me. I guess scientist from alaska are also corrupt by industry LOL Typical ENGO distraction. What I find really delusional is the lengths engo will go to run any industry thought the mud. Sat that sportfishing now faces these same accusations by the same ENGO pundits.

PISCINE ORTHOREOVIRUS (PRV) IN THE PACIFIC NORTHWEST APPEARS TO BE OF LOW RISK TO WILD PACIFIC SALMONIDS

This summary report contains the most current information available on PRV risk to wild Pacific salmonids contributed by expert fish health practitioners and researchers in the Pacific Northwest Prepared By The Pacific Northwest Fish Health Protection Committee By T.R. Meyers Alaska Department of Fish and Game Juneau Fish Pathology Laboratory Informational Report No. 10

"The PRV strain present in indigenous Pacific salmon in the PNW, historically and experimentally, appears to be relatively benign and unable to produce significant disease or HSMI in native salmonids."
 
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Im actually enjoying going through the links, oh my, there are so many, I see a post and I'm like wholy crap here comes a see of blue from anti aquaculture pundits then wham, sea of blue! Then I go through what I can, cuz I don't have a whole day or two or sometimes a week, to go through one post of links and I see what's in them. While the sea of blue is over whelming, which is its intent, I find that when one actually gets into, what you can manage, seems for me about 20% of links provided by one side of the "discussion".
This sea of blue, there's another name for it but I received a warning for using it previously, is an interesting presentation. It gives a reader a subtle option to inflict their bias in a manor that relieves a commitment to the facts as contained in allllll the links. Most people aren't willing to, and rightfully so, dedicate much effort into reviewing that much information from a single post however they will chose a side based on the staggering amount of information being put up at once. This is called "unconscious bias".
While the sea of blue gives the impression of a good argument it is far from that, particularly when the volume is so overwhelming that it's pretty clear anyone who wants to respond is going to lose at least a day going through it.
Anyways, enjoying going through what I can and understanding for myself what is true and what is not. As far as going in circles, ya, it is what it is. Just debating if aquaculture is improving and I think it is when you put aside the rhetoric, ie the what seems to be a absolutely urgent effort to stick salmon farming with the introduction of European PVR. The urgency in this is telling.
 
Removing fish farms made it into the mandate letter. The government actually has a decent track record when it comes to implanting things that make it into the letter. It’s easier to leave stuff out of the letters if you don’t want to do then then put it in .

Also note the letter does not say transition to to land it just says transition away from open net farms.

The farms on the east coast will remain

I feel for the people in port Hardy who have been put though a horrible logging strike, reduced salmon and commercial fishing and now this.

Operations like hardy boys who server the sports fishing community do so because 70% percent of their business is from smoking Atlantic salmon.
 
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