Atlantic Salmon farming now supports a multi-billion dollar industry worldwide. In Scotland the Atlantic salmon aquaculture industry has a £1.4 billion turnover, supports 8000 jobs and predicts 30 per cent growth by 2020.
As we attempt to move farmed Atlantic Salmon (carnivores in the wild) to more ecologically sustainable plant-based feeds, understanding the role of their gut bacteria becomes a vital consideration.
Researcher Dr Martin Llewellyn (Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow) and co-workers in Ireland, Scotland, Canada, USA and Wales have now taken a first step towards understanding the role of salmon gut bacteria in salmon health.
After two years intensive sampling from adult salmon feeding grounds in West Greenland, returning adults and freshwater juvenile salmon in Canada and Ireland, the researchers have developed the first compete picture of wild Atlantic Salmon gut bacterial diversity across the distribution of the species.
The data shows that bacterial community composition within the gut was not significantly impacted by geography.
Instead life-cycle stage (parr, smolt, adult) strongly defined both the diversity and identity of gut microbial assemblages in the gut, with evidence for community destabilisation in migratory phases.
Amongst other observations, Mycoplasmas were recovered in all life-cycle stages in huge abundance, suggesting a potentially vital role for this class of bacteria for gut health.
Dr Llewellyn’s data pave the way for fundamental research in this field, including the development of probiotics, pre-biotics and even whole artificial bacterial communities to improve farmed Salmon health and reduce the impact of Salmon aquaculture on wild fish stocks.
