Farmed salmon can spread deadly illness to wild counterparts

If you’re the type who just buys wild fish and doesn’t touch the produce, be aware that the two may not be as far apart as you might think. New arrival the study Published on Science Advances on Wednesday Fish orthoreovir-1, Or PRV-1 may have spread from the Atlantic Ocean Salmon aqua farm For wild Pacific salmon.

PRV-1 is a common virus in salmon Cause Atlantic salmon A population with inflammation of the heart and skeletal muscle.Also associated with Another illness It is becoming more and more common in Pacific salmon, especially wild chinook salmon. Population is declining..

In Chinook salmon, PRV-1 jaundice/anemia, This causes the red blood cells in the fish to burst, turning the abdomen and areas under the eyes yellow. More importantly, it can lead to fatal liver and kidney damage in wild salmon.

Atlantic salmon farm has emerged Pacific Northwest, Including near Area where wild salmon run.. So far, salmon farms have played a role in the dissemination of PRV-1 to wild salmon. region It’s a big question mark. To To clarify, the authors studied various gene sequences of PRV-1 (or all nucleotides that make up all chromosomes of the virus) around the world, dating back to 1988.

“We sequenced the genomes of viruses that infect 86 different fish in BC. [British Columbia], And we combined these with previously published sequences to perform the analysis, “said Gideon Mordecai, lead author of the study and professor at the University of British Columbia. EEarth, sea, And the Atmospheric Science Department, I wrote by email.

By sequencing The order of the nucleotide genomes that make up the DNA of a virus allows scientists to track its evolution.Differences in gene sequence can be provided Clues about how the virus originated and spread to different locations..We have a lot application, How scientists Have got Traced covid-19 mutation..

“This was done on a different scale to track the transmission of salmon between different populations off British Columbia, not just between the oceans, but more locally.” Mordecai said.

The author’s findings indicate that the strain of virus found in the Chinook population in the northeastern Pacific comes from the same strain as the case found in the Atlantic Ocean. They estimate that this spread occurred in 1989.

It’s much faster than the first report of jaundice /Anemia caused by the virus in 2002. However, the timeline makes sense, as it suggests that the virus arrived in the Pacific at about the same time that salmon farms in the region imported Atlantic salmon eggs from Europe. When the eggs fertilized and hatched, the fish may have carried the disease to the wild Chinook population.But Include The authors do not prove that eggs have caused the virus in Pacific salmon. The timing is right.

Currently, PRV-1 is rampant on farms Atlantic salmon Raised.. The authors found that more than 97% of all Atlantic salmon farm fish were infected with the virus by 18 months before the aquaculture cycle. From those farms, the author’s findings suggest that PRV-1 is constantly spreading to wild Pacific salmon.

The method of spreading the virus is pretty terrible. It is transmitted through infected fish droppings and carried through water.It then infects other fish through the gills and skin, And the intestines.

This is not just disgusting. IIt can also be devastating to the wild Chinook population. Already facing many threats Invade humans like overfishing Development, and loss of habitat. The authors suspect that infectious diseases may also contribute to their decline.

According to Mordecai, the decline in chinook salmon populations has caused havoc to indigenous peoples. Those who depend on them for the nutrition and fishing economy. The decline has also driven the ecosystem out of destruction. A variety of wildlife, including killer whales, bears and seals, prey on fish. Thankfully, the author also suggests several ways policymakers can tackle these issues.

“Our study emphasizes the need for strong regulation of aquaculture that may prevent future loss of wild populations, which is exacerbated by PRV-1 and other emerging infectious diseases. It’s possible, “the author writes.

For example, PRV-1 is very common in Canadian Atlantic salmon farms. However, the country does not classify the virus as a pathogen.Mordecai, the country said, to better regulate the spread of the disease should Formally recognize The role of PRV in salmon disease. He said there is again An ever-increasing number of phones Move the fish farm from sea to land Or otherwise contain them In some way..

“These will largely solve the problem of transmitting the disease to wild fish,” he said.