Written by Soledad Francke
Although there is connection and communication between the aquaculture industry and science, there is still lost energy; ideas not reaching their proper destination and the potential for new commercialized products not becoming a reality.
There are several drivers considered to establish priority and locate the best candidates for new species to be produced. These drivers include consumer preference, cycle length and growth speed, cultivation conditions, diet composition, space, and water requirements to name a few.
Innovation is obviously another valid driver criterion and tends to look at species with unique characteristics to enhance differentiation in the market - like tambaqui fish farmed in Brasil, which is an intramuscular boneless fish. Tambaqui is of high interest not only for its sole production but for the genetic possibilities it brings.
Species of interest are not just for consumption — Ballan Wrasse (Labridae) have been used for sea lice control in salmonid production for more than 30 years. Lately lumpfish, which continue to feed on sea lice at low temperatures, has generated a boost in cleaner fish production and research lines in Norway. These species are a sustainable and welfare focused way to contain the sea lice problems.
The four most promising aquaculture species are Atlantic cod, Atlantic halibut, Artic charr and Sablefish. These industries forecasted a combined net worth of $880 million by 2020. Today we can confirm that those species are still on track but others, such as Amberjack and Cobia, are positioned to become much more prominent.
But what do these species have in common? Except for a certain level of acceptance Artic charr has to zooplankton at certain times of the year, they are all carnivorous.
The criteria that prevail in this selection are the growth speed, the ease of feeding and the conversion of protein from the diet into protein from the product.
One of the selection criteria that could represent a long-term sustainability solution should be locating herbivorous or omnivorous species that allow greater flexibility in the origin and content of proteins and oil in their diets, thus reducing the need for fishmeal. Fishmeal is becoming more and more scarce; working with herbivorous and omnivorous species would allow better management of raw materials.
In 2007, a study comparing feed consumption of carnivores and herbivores found that production of one kg of fish requires about 500g of protein for mullet (herbivore), and only about 400g for grouper (carnivore).
Herbivore fish, like the mullet, could use low energy, protein diets from vegetable sources since they have a larger stomach for storing higher volumes of feed. On the other hand, the diets of carnivores should be more concentrated in protein and nutrients.
For those not familiar with aquaculture, Feed Conversion rate in salmonids is 1-1.3 kilogram of feed per kilo of fish produced; an incredible ratio compared to mammalian species.
Throughout the years, tremendous research has been done to make carnivorous species more “vegetarian”, but this path has obviously generated new challenges for the health and fatty acid profiles of these species. Complementary strategies are required to maintain robustness, and resistance to environmental stressors for fish welfare.
A greater connection between science and industry is still required to join forces in defining new species to be produced. Technologies exist and it is a matter of allocating these resources to work on adapting them to different environments and requirements. With the help of genetic tools, a more sustainable future and with diversity of species, we can reduce breaks in the food chain due to overproduction and over exploitation.
The views expressed in IMV Technologies’ blog do not necessarily represent the views of the IMV Technologies Group but solely those of the blog post’s author