The effect of triploidy on the performance, gut microbiome and behaviour of juvenile Atlantic salmon (Salmo salar) raised at low temperature

•Impact of triploidy is assessed in juvenile Salmon raised at low temperature.•Farming performances, behavioural traits and gut microbiome are compared.•Differences between triploid and diploid salmon are reduced by low temperature.•Diploid and triploid fish display similar swimming activity and boldness traits.•Gut microbiome seems to be quite similar between both fish categories.