What characterizes a feed-efficient fish?

Foods of Norway researcher Hanne Dvergedal

Foods of Norway researcher Hanne Dvergedal

Photo
Liv R. Bjergene
Aquaculture has increased from 7.7 million tons of farmed fish in 1985 to 70.1 million tons in 2013. The estimate for global demand for fish by 2030 is 150-160 million tons. One way to increase production is to select the most efficient animals for future generations in aquaculture production.

Fast growing and high feed intake

It is well known that individual variation in growth efficiency may partly be explained by differences in social status or variability in digestion, absorption, utilization and metabolism. Today, the traditional way of selecting animals for feed efficiency is through indirect methods such as growth rate, based on the assumption that growth rate correlates with feed utilization. The outcome is faster growing fish, but also fish with a higher feed intake. Thus, overall result need not be increased feed efficiency.

Measure protein turnover

“In my research, the aim is to develop direct methods to select for feed efficiency in Atlantic salmon. Protein metabolism is a major determinant in the conversion of feed into growth. I therefore measure protein turnover in muscle, liver and mid-intestine of Atlantic salmon”, Foods of Norway’s PhD-student Hanne Dvergedal explains.

Altogether 510 fish will be tested in the pilot project. Dvergedal aims to distinguish the genetic variation within and between families in their ability to produce high quality fish products on as little feed as possible and still promote good health of the fish.

“A possible direct way to select for feed efficiency is therefore to develop a method to measure protein turnover at an individual level and compare families”, Dvergedal says.

Published 13. October 2016 - 11:19 - Updated 10. March 2017 - 14:27