Researchers at São Paulo’s Fisheries Institute, with FAPESP support, compared the growth of rainbow trout of different colours at the salmon farming research centre in Campos do Jordão. The study was published in Aquaculture Reports.
The fish were raised in tanks with the same temperature, water quality and feed. About 8,200 fry hatched and were divided into four colour groups: white, yellow, cobalt-blue and wild. Ninety fish from each group were weighed at 60, 120, 180 and 270 days.
Wild trout grew faster at first, but by six months yellow fish averaged 123 grams, compared with 119 for wild ones, and the gap widened. At commercial slaughter weight, yellow trout reached about 300 grams, compared with 237 for wild and 145 for albino fish.
Brazil produces about 1,600 tonnes of trout a year. The researchers see commercial potential for aquaculture and recreational fishing, and are also working on a trout with orange flesh obtained through special feed and on improving the species’ nutritional value.
