Can Carnivorous Fish Become Vegetarians?
Steelhead or Rainbow trout (Oncorhynchus mykiss). Photo credit: USFWS.
A recent study has determined that carnivorous fish are capable of becoming vegetarians.
Aquaculture is growing in order to meet the increasing demand for seafood. One of the biggest problems with aquaculture is that most of farmed fish are carnivores and require fishmeal and fish oil as feed. These fish can’t be fed a plant-based diet because they don’t grow as much, are not as healthy and can’t produce healthy offspring.
“The availability of products for animal feed will be a central issue in the coming years,” the author wrote.
In this study, the researchers attempted to turn rainbow trout (Oncorhynchus mykiss) into vegetarians. To do so, they immediately switched the trout to a strictly plant-based diet and through selective breeding, were able to successfully convert them to a vegetarian lifestyle after only one generation.
The authors wrote that “domesticated populations of rainbow trout have the genetic potential to adapt to major dietary changes.”
They conclude that by combining environmentally friendly and nutritionally balanced vegetarian diets with selective breeding programs, “it would be possible to improve fish welfare and to ease the transition towards a more sustainable aquaculture production.”
To learn more:
Find the results, published on Sept 28, in the journal PLoS ONE: Selection for Adaptation to Dietary Shifts: Towards Sustainable Breeding of Carnivorous Fish
Steelhead/Rainbow trout. Photo credit: NMFS/NOAA.
Copyright © 2012 by Marine Science Today, a publication of Marine Science Today LLC.
