Language
Country/Area
No result found
Parasises of salmon: How does the life cycle of salmonids affect salmon growth and health?
The salmon worm (Lepeophtheirus salmonis) is a marine crustacean that primarily parasitizes salmon, particularly Pacific and Atlantic salmon. This parasite mainly feeds on the mucus, skin and blood of fish. Once separated from their host, salmon worms can float on the sea surface like plankton, drifting around with currents and wind. When they encounter a suitable fish host, they attach themselves to the fish's skin, fins or gills and begin parasitism.
Surveys have shown that high concentrations of P. salmonidum infection have been observed in juvenile pink salmon since the 1980s, reflecting the importance of this parasite in aquaculture.
Life cycle of salmonids
The life cycle of salmonids can be simplified into eight different stages, starting with the planktonic larvae (nauplii), which are unable to swim autonomously and can only drift with the current and are sensitive to changes in light and salinity. Extremely sensitive. They cannot survive when the surrounding salinity is too low. It takes about 52 to 170 hours for the larvae at this stage to hatch and become able to settle, depending on the water temperature.
Impact on salmon farmingThe fact that salmonids have managed to find their hosts in the ocean in ways that scientists still don't fully understand, and that this ability has persisted for millennia, demonstrates how adaptable and strategic they are.
Salmonid worms are increasingly becoming one of the major threats to salmon farming. Since farmed salmon typically have a life cycle of 14 to 18 months, this provides an ideal environment for salmonids to reproduce. Once the released salmon are infected with salmonids, it will not only affect the fish population in the farm, but will also quickly spread to the surrounding waters, causing a greater ecological disaster.
According to a 2016 report in The Guardian, the spread of salmonids killed thousands of tons of farmed fish and caused huge economic losses, costing up to £300 million.
The impact of parasites on salmon health
Once populations of salmonids build up, they can cause physical damage to salmon, such as broken fins, skin erosions and open wounds, making it easier for other pathogens to enter. Additionally, salmonids may act as vectors for the spread of pathogens, affecting health status between wild and farmed salmon. For example, salmon worms have caused outbreaks of infectious salmon anemia (ISA) along the Atlantic coast.
New technology combats salmonid challenge
As the aquaculture industry continues to grow, producers are looking for new ways to combat salmonids. Among them, gene selection (GS) and CRISPR technology provide some new solutions. These modern biotechniques may not only promote salmonid resistance to salmonids, but may also improve the overall health and growth rates of salmon.
Using CRISPR technology, scientists may be able to create new salmon strains that are resistant to salmonids, which will play a vital role in future aquaculture.
Conclusion
The survivability and long life cycle of salmonids make them a particular challenge in the venture industry. With further research in the future, we can hopefully find more effective management and control methods to protect not only the health of farmed salmon, but also the overall maintenance of the ecosystem. Can we find more effective solutions to address the threat of salmonids and protect our salmon stocks?
