Jun 5, 2022
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What do salmon bite and where

What do salmon bite and where

Photo: Yuri Smityuk/TASS

Salmon feed is purchased mainly from Norway, Denmark and Finland. Due to the current complication in relations with Western countries, the import of fish feed for this valuable species tends to zero.

According to the Federal Agency for Fishery, for certain areas of fish farming, including salmon, 90–95% of feed is imported. In this regard, the department proposes to subsidize the construction of factories producing fish feed. But this will take from 16 months to 2-3 years, therefore, in order to provide fish farmers, the Federal Agency for Fisheries proposes to organize work with existing producers of compound feed for the needs of agriculture.

— Import substitution of feed for salmon species is a super-relevant project. Because today the supply of fish feed from abroad has either become much more expensive, or has completely stopped, – believes Alexander Kolomeytsev, Head of Science and Innovation Department, Krasnoyarsk State Agrarian University:

– Fish is mainly an ocean resource, but it is quite renewable with proper technology. And here we came to the conclusion that we need to work on import substitution of feed for two reasons.

Firstly, the main part of fish food is also fish, but less valuable. This calls into question the inexhaustibility of these resources. Therefore, we offer another option – non-traditional protein raw materials. And this, no matter how unpleasant it may sound, is a fly larva or gammarus (a small benthic crustacean that lives in fresh and brackish water bodies – ed.), which is found in large numbers in our Khakass lakes.

Our partners from the Krasnoyarsk Scientific Center of the Institute of Biophysics of the Siberian Branch of the Russian Academy of Sciences have calculated that the reserves of gammarus will be enough for the development of aquaculture in the region. So, as a protein component, they took a gammarus or a fly larva, which is also enough in nature.

In addition, we used a combination of our original Siberian plant selection. This is a camelina, which has unique properties, it has a very good balance of fatty acids, and its protein content is very decent. And we also have two unique varieties of soybeans – these are “Eos” and “Zaryanitsa”. It is unique not for its special productivity, but for its composition, the same proteins, fats and carbohydrates. And on the basis of twelve components that are produced in the Krasnoyarsk Territory, we have compiled eleven feed formulas for aquaculture.

Now we are testing them. That is, we have completely worked out the composition: both vitamins and minerals – for salmon, for trout – everything turned out very well, we are proud of this achievement. It remains only to decide on purely physical properties (all the necessary properties must be observed so that the feed does not soak and sink as it should), and it is possible to transfer the recipe and manufacturing technology to production. Our proposal is being considered by the Krasnoyarsk feed mill and the Krasnoyarsk holding Goldman Group. We will conclude an agreement with them and exercise architectural supervision.

“SP”: – What types of salmon are bred in the Krasnoyarsk Territory?

— Trout is bred in closed aquaculture reservoirs. The famous fish of the Yenisei group – grayling is found in our country, this is our original fish. It is salmon, although its meat is not red. However, it’s salmon. In general, we have one of the largest farms – “Ruslov” deals with many types of fish – from sterlet to trout, we like to cooperate with them, we are glad that they do not go to France for technology, but turn to us. In general, we have seven fish farms operating on the territory of Eastern Siberia – this is Khakassia, the Krasnoyarsk Territory and Tyva. But there is room to grow. And the market is growing, and the population has a clear need.

“SP”: – The government has already resolved the issue of opening new factories for the production of high-quality fish feed. What recipe will provide this quality?

– Feed formulations are usually not published in the public domain. But from the obvious to date, there are two main ways. This is the use of other fish, such as anchovies, to make flour. I have already mentioned the depletion of fish resources about the disadvantages of this. And the manufacture of meat and bone meal – from the meat of livestock or poultry. In this sense, our technology is simple, environmentally friendly and sufficiently tested in the reproduction of aquatic fly larvae.

“SP”: – The presence of flies in what will eventually become food for humans is somehow embarrassing …

– There is such a thing – “bioconversion” of feed. That is, what you ate, and, accordingly, what your body received when eating a certain type of food. For salmon, a very important property is the balance of fatty acids – polyunsaturated and saturated. So, for a person, polyunsaturated acids are very important, he also cannot produce them with his body, but must receive them with food. And such a source, one of the richest, are salmon fish.

And this is the first and most important prevention of cardiovascular and metabolic diseases. Studying the biology and physiology of the fly larvae, we saw that when adding fly larvae to the food substrate, we can increase the content of those same polyunsaturated fatty acids in it, which, again, get through the fish feed, and it can use all its genetic capabilities, which in it is “wired”, to implement. Thus, we get a full-fledged salmon fish containing polyunsaturated fatty acids, but not caught in the wild, but produced under artificial conditions.

And gammarus is interesting and unique in that it is found in sufficient quantities in the Khakassian lakes of the Krasnoyarsk Territory. And most importantly, it turned out that the gammarus has no natural enemies and competitors in these reservoirs. Therefore, our current experiments confirm that its population quickly recovers after being caught.

That is, there is no negative environmental effect that we get when catching anchovy. Thus, two of our advantages are revealed. First, we have learned how to prepare a special substrate for the fly larvae and it turns out to be enriched, and the “bioconversion” of the feed is set up so that significant amounts of polyunsaturated fatty acids are formed in it.

And then they get into the food and get into the fish. And secondly, gammarus is highly nutritious in terms of proteins, vitamins, and the same fatty acids.

Of course, we understand that we will not completely solve the problem either with a larva or a gammarus, but with these two raw materials, the problem with mixed feed for salmonids will be removed. Such feeds will be balanced and attractive to salmon – unlike feeds that have added meat and bone meal of agricultural origin – from livestock. The fish has a well-developed sense of smell, and its feeding habits are based on olfactory sensations. And if something that smells like cattle gets into the reservoir, then the salmon is unlikely to be interested in this. But if it smells like a fish or a fly larva, which, as all fishermen know, “pecks” perfectly, then feed instincts work.

“SP”: – Is your recipe universal? Is it suitable for all regions of the country?

— There are eleven agricultural, agroecological zones in our country. And each of these areas has its own characteristics. Therefore, we are ready to make a recipe based only on the raw material base of the region in which the fish farm is located. The regimes for keeping fish under aquaculture conditions are, in principle, the same, standardized from Kamchatka to Kaliningrad. But feed raw materials have different properties. Therefore, we will need to study the quality of raw materials in order to optimize these diets. It’s just a small adaptation.

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