Past and Present

My name is Murray cod, not the "big fish" deep-sea cod called by Qingdao natives, I am a freshwater fish from Australia Murray River genetically. A group of like-minded adoptive parents from the scientific research team of Ocean University of China took me back to China. After years of hard exploration, I successfully settled down in Hetoudian Town, Laixi, Qingdao.

    Now, they all praise me as a strong and brave body, delicious meat, with high value of the "noble fish", I was also honored to be selected by the Ministry of Agriculture and Rural Affairs in 2023 the second batch of National Famous and Excellent New Agricultural Products! I grew up in a land-based circulating water system, in order to raise me, adoptive parents, from beginning to end, spend much money in food, housing and equipment, even the "nanny" are equipped with many. Now, my adoptive parents have prepared the exit qualification for me at the customs, and I can export to the world at any time with my current strength.

Inadvertent Meeting

Why did my adoptive parents take care of me? It's a long story. In 2010, Academician Mai Kangsen and Professor Gong Qingli from the College of Fisheries of Ocean University of China went to Australia to attend a seminar abou the abalone family. During the period, a fish in a Chinese restaurant caught their eyes, and this fish was my native Murray cod.

They kept me in mind at that time, because of the good taste and other excellent characteristics, they have been trying to bring me back to China, after many efforts, finally at the end of 2011, brought me to China. I am also called by other names, such as the Australian spot, the dragon spot, the worm perch. My body is spindle shaped, the back is yellow-black or dark-green, the abdomen is light yellow-white, and the sides of my body have beautiful patterns. My hometown is in the south of Australia, Murray Darling waters. Afraid of light, I am not active during the day and often roost in the dark with sunken wood or water grass in the natural waters, while the most active at night in summer. My population is the largest individual freshwater fish in Austrsaila, the length of grown fish individual would reach 80-100 cm. It is said that one was ever found to be 1.8 meters long, weighing 113 kg and living for hundreds of years of my population.

    The adoptive parents said that because of the waste of water resources and greater risk of traditional aquaculture, the production of food protein for humans needed to be more stable. In consideration of the chicken and pig families have turned into industrial production, the adoptive parents also designed a farming system for me specially, called industrial circulating water culture system, of many advantages such as water saving, risk control, and the most important is to dig my other value.

Now, my family has settled down in Hetoudian town, Laixi City. Qingdao Qicai Seed Technology Co., Ltd. covers an area of 150 acres of land exclusively, and adoptive parents also raises other high-end fish. The mandarin fish family and the salmon family also live here. I'm actually not too worried about my status, my strength determines that my current status will not be shaken.

We are group brood. Group breeding requires a relatively large amount of individuals, and the selection of growth traits is to select the parents with fast growth, good body shape and strong disease resistance as the candidate. In the breeding process of parent fish, the best individual is selected and bred continuously as the final parent. directly importing broodstock from Australia is very expensive. Taiwan ever directly imported parental fish from Australia where a pair of Murray cod parental fish less than 20 pounds cost 150,000. In the natural waters of Australia, we are protected animals and can not be directly fished without permission. Our species only exists in the Murray River, so the Murray cod is also transliterated. In the 1970s, the local government took the lead in protecting the resources of our species. Then they research bresding in wild populations, and by the 1990s we were commercialised on the farmed end and were the largest in all of Australia's freshwater waters.

A happy journey surrounded by nannies

Our population is very low-key, if the light is too bright, we will hide in the shadow, and we are reluctant to eat under the strong light which affects our growth and development. Compared with other freshwater fish, we are relatively fierce, especially when the breeding density is low. Where I occupy, any kind of trespass on my territory that can not be done, we must rush to theory and force them out. In particular, when we are not fed after being selected as commercial fish and in a state of hunger, we're gonna bite everything, head or tail or whatever!

In order to make me more outstanding, my adoptive parents hired a number of nannies to help me improve my physique. There are nutrition nannies, responsible for my nutrition intake, to ensure the quality, but also invited disease treatment nannies, as well as prevention and control, technical equipment nannies, these nannies are very experienced and expert, those much attention to me made me popular.

   People say that we have an earthy smell, which is of course the nature of fish. In order to reduce the smell of  earth on us, scientists have specifically studied the causes of the formation of earthy smell in order to find ways to cope, and they really cocern about it. Now I hear that the NASDAQ capital market has also paid attention to our advanced culture models. And land-based circulating aquacultured salmon has been already listed, which is to compete with me. As good as the salmon is, we are not vegetarian.

Behind the scenes>>

Ten years to introduce fish, ten years to breed fish

Professor Gong Qingli of the College of Fisheries of Ocean University of China is also the head of Qingdao Qicai Seed Technology Co., Ltd. He said that good taste is the primary prereqisition for marketization. After returning to China in 2010, they discussed with relevant leaders of the Science and Technology Department of the Ministry of Agriculture. When the leaders heard the idea of introducing Murray cod, they were also very excited and supportive.

    Zhang Xianliang, former president of the Chinese Academy of Fishery Sciences, said: "Owing to the particular richness of sea fish species in China, the significance of introducing a sea fish is very limited. While the freshwater fish species are relatively monotonous and normal, there is an urgent need for some high-grade freshwater fish." In our country, most people (about 1.2 billion people) consuming fish live in the inland, only 200 million people live on the coast, and the people who eat freshwater fish are much more than the people who eat seawater fish."

    Therefore, the introduction of murray cod has been strongly supported by all parties in China. Since 2011, China has introduced fish fry from relevant institutions in Australia and carried out aquaculture. Professor Gong Qingli referred that Academician Liu Shaojun said in the academician forum in Shenzhen in May 2023: "We should use a global vision to look for some species with excellent biological germline and traits around the world, bring them back to develop our breeding industry, and meet the needs of the people in our country to continuously improve their living standards." The era of industrial aquaculture is coming.

Professor Gong Qingli introduced that the Laixi Park in the first phase of construction can raise 200,000 adult fish per year, and it can raise 500,000 to 600,000 adult fish in the second phase, and it will reach 4 million to 5 million in the end, which provides a solid foundation for promoting the "seed industry revitalization" plan and solving the problem of "jam neck" in the seed industry.

The project uses industrial recirculating aquaculture in order to improve the utilization efficiency of water resources. The water of aquaculture passes through multiple use and returns to the fish culture system after treatment. The proportion of recycling water reaches more than 95%, basically realizing the full utilization of water resources, which belongs to the advanced water-saving fish culture industry. At present, the domestic industrial circulating culture is in a infancy stage, there are not many companies with this technology. And the internationally leading high breeding density is even more rare, so Qicai belongs to the technology-leading company.

    In addition, Professor Gong Qingli said that people's preference for marine fish and freshwater fish is because of the difference in taste, both types of fish are rich in protein, people in inland areas think that the sea is fishy, and people in the seaside think that the freshwater fish is heavy. In order to lighten the earthy taste and make the fish taste better, their team also carried out an investigation and research on the source of earthy taste, analysing what ingredients are made of, which bacteria produce them, and study how to eliminate them and improve some of the factors that taste good.

High quality and high price, 200 yuan a kilogram

Professor Gong Qingli told reporters that digitization is the trend of aquaculture, developing from mechanization, manpower to information, attention was paid to the collection of information, and then to intelligence, through the collection of information, through automated means and feedback back to achieve the purpose of control. The next step of aquaculture in China is to achieve information and intelligence. It will take a certain amount of time to be fully intelligent, but information can be done.

    The aquaculture industry uses industrial circulating aquaculture system to raise fish, and the future aquaculture products must be sold all over the world, and the "key" of global market sales must be obtained. With the help of the Entry-exit Commodity Inspection and Quarantine Bureau of China's Customs at the beginning of the construction,  the Laixi Park passed through the "Entry-exit Aquatic Animal Farms" approved by General Administration of Customs, turning a Chinese fish into international.

    Professor Gong Qingli said that the development of aquatic breeding industry is closely related to the aquaculture industry, and Qingdao is also very concerned and very supportive. In the future, the Blue Seed Research Institute and Aquaculture Breeding Park will be established in Qingdao to effectively promote the further development and promotion of Qingdao aquaculture industry.

Liu Ming, general manager of Qingdao Qicai Seed Technology Co., LTD., is also a member of the scientific research team of Ocean University of China. Liu Ming introduced that what were directly imported from Australia in 2011 were newly hatched fries. In the five years from 2011 to 2015, the team introduced a total of five million murray cod hatchlings, also known as splash, and bred them in the breeding process. At present, murray cod has achieved full artificial breeding, the broodstock is selected out and cultured in the fully closed cycle breeding system of Qicai.

    After the sexual maturity of broodstock, the parental fish in good state will be picked out for oxytocin. After  oxytocin, to artificial egg retrieval, artificial sperm retrieval, artificial fertilization, artificial hatching, and artificial cultivation of seedlings are carried out. At present, the feed is divided into two kinds, the small fry that have just opened should feed on biological bait, which is changed to artificial feed for domestication after a period of cultivation, and it is converted into grown-fish feed as it grows up step by step,. At present, Qicai has also developed a special feed for murray cod, which can meet the nutritional needs and growth needs of fish, and also meet some special requirements of high-density circulating water system for feed.

   The murray cod in the first year grows relatively slow, which can basically grow to commodity specifications in the second year, weighting 3 ~ 5 pounds. Generally, it takes about 14 months to grow to the marketable specification with a weight of about two kilograms. At present, the price of murray cod commodity fish in the wholesale market is close to that of high-end seawater fish, because the fish of cultured by Qicai has no antibiotics, no drug residues, and no parasites. So the murray cod in the high-end market has a higher price, and some of which priced of 120 yuan per catty.

    Liu Ming introduced that the team has explored a number of seawater fish species before, but the murray cod is the first freshwater species which can also be cultured in brackish water like some domestic river estuary areas. The murray cod is one of the most difficult fish they've ever cultivated. The first is that the sexual maturition of the murray cod spends too long, basically needing about 8 years, so the period of perparing broodstck is very long. Second, its spawning capacity is very limited, generally female fish of more than 20 pounds produce about 30,000 eggs each time, and a carp of 20 pounds can produce millions of eggs. The reproduction capacity of murray cod relatively weak.

    In addition, in the domestication stage of fish fry, feed conversion is also relatively difficult. In the breeding process, the squama of murray cod is too thin to resist parasites. The current land-based recirculating aquaculture model is very suitable for the growth of murray cod. Because of the high tolerance of murray cod to high density, the breeding density is generally maintained at 100 to 150 kg/m3 water, up to more than 300 kg.

Efficient water saving, and also "earn" food

According to reports, the north factory area of the Laixi Park is a white earth mine. Previously, the white soil was dug to form a pit of about 400 acres, with perennial rainfall and surface water accumulation. At present, the water for daily replenishment in the Laixi Park mainly supplied by relatively deep water of the white earth mine after pre-treatment.

    Liu Ming said: "This is also an effective use of the land area of the mining area, solving the problem of where the facility agricultural land comes from and providing a part of the solution, which is of grest ecological significance." Because the land management in China is very strict, the red line of 1.8 billion mu of arable land cannot be broken. Now facility agriculture has become a starting point for rural revitalization, without the occupation of basic farmland, using waste mining areas and some abandoned land, non-arable land to develop facility agriculture kills two birds with one stone."

    Land-based industrial recirculating aquaculture is also the key development direction of national facility fisheries. This production mode saves land, with high output efficiency, a standard breeding pond is 6 meters in diameter, the annual output of a standard pond is about 10,000 kilograms, equivalent to 5 ~ 10 acres of high standard pond, equivalent to more than 300 acres of water surface production, which is very land saving and efficient.

    According to reports, per capita freshwater in China is generally few, only equivalent to about 20% of the world's per capita freshwater. At the beginning of the designing of the Laixi Park, we ran to the purpose of saving water concerning that Qingdao is a structural water shortage city. In the whole aquaculture system, there is a critical part called mechanical filtration. Mechanical filtration requires high-pressure water to bring out fish manure, leftover feed and suspended solids to keep the breeding environment clean. The daily water exchange of traditional water aquaculture is 600%-1200%, while now the daily water supplement of Laixi Park is only about 2%, which two are not in a magnitude, so land-based recirculating water aquaculture has obvious advantages in water saving.

    And even this 2% of water change every day will not be wasted. After the water takes out the residual feed and feces in the system, it goes through a series of technical treatment to achieve the integration of water and fertilizer, and can be used to grow hydroponic vegetables. In summer, the water enters the lotus pond and the rice field. The lotus pond and the rice in the field grow very well. Water from rice fields can also be poured into dry fields to maximize the use of water resources. Qicai is the first one to grow rice in Laixi City, the water changed every day is not drained away, and the park can consume itself.