The world's first large-scale artificial breeding technology of Murray cod has achieved a breakthrough

China Ocean University

Murray cod introduction and breeding project research group

Murry cod (Murry cod) produced in the Murry River Basin of Australia, since 2011, by the Ocean University of China and Qingdao Qihao Biotechnology Co., Ltd. joint large-scale introduction of China, the industrial breeding of circulating water research, and and the breakthrough in breeding technology, the successful breeding of Murray cod finished fish quality, delicious taste, the adult fish market is in short supply, the price is high in the forefront of the domestic freshwater fish list.

Maccullochella peelii is taxonomic, belonging to the order Perciforme, percichthyidae of the family Percich, and percichthyidae of the family Percich. This fish originated from the ocean and is one of the largest freshwater fish in the world, with a maximum weight of more than 100 kg. Because the Murray cod has a special appearance and flesh is firm, white and tender, delicious, no fishy taste, and has a faint unique fragrance, the meat is tender and thorny, the taste is far better than the grouper and bamboo shoot shell fish, rich in four kinds of flavor amino acids and EPA and DHA, nutritional value is quite high, in Australia the evaluation is very high, known as Australia's "national treasure fish" reputation.

Murray cod in Australia was developed into a cultured species since about 2000, there are currently about 3 large-scale aquaculture enterprises in Australia in the breeding production, the annual output of about 500 tons, for the Australian market and some exports to the international market. At present, in addition to the large-scale aquaculture of Qingdao Colorful Aoban Aquaculture Company, there are several other companies in China that carry out aquaculture. The culture method is mainly circulating water factory culture, with an annual output of hundreds of tons.

Ocean University of China and Qingdao Qihao Biotechnology Co., Ltd. have cooperated since 2011 to introduce breeding of Murray cod from Australia, and with the support of the "948" project of the Ministry of Agriculture, etc., have carried out scientific and technological research and development of industrial aquaculture of Murray cod circulating water, and have successively carried out the development of breeding system design, water quality monitoring, special feed for Murray cod under circulating water conditions, automatic feeding, disease monitoring and prevention and control, oxygen efficient dissolution, UV-ozone combined disinfection, carbon dioxide removal and high-density breeding. The systematic technology construction for the industrial high-density breeding of Murray cod circulating water has been completed, and the breeding density has reached the current international leading and domestic highest level of 150-200 kg/M3 water body.

The supply of seeds is the main factor restricting the further development of the Murray cod farming industry. Murray cod due to the age of sexual maturity, need more than 6 years of age to achieve sexual maturity, less spawning, breeding environmental factors are demanding, so far the main use of fry production methods or broodstock placed in the fish pond, the construction of fish nests, let it mate naturally, spawn and fertilize, retrieve the fertilized egg mesh curtain for incubation and breeding, basically is a natural egg collection semi-artificial nursery method, it is difficult to obtain a stable number, excellent quality of large-scale commercial fry supply. Domestic large-scale culture of Murray cod still needs to import millions of fry from Australia every year to carry out aquaculture production.

Since the introduction of breeding Murray cod in 2011, the scientific research team of Professor Gong Qingli of the Ocean University of China has begun to carry out the preparation of artificial seedlings, and has introduced 5 million fry for breeding, from which according to the body size, body length, growth performance, disease resistance, body pattern, male and female individuals and other epigenetic traits for screening, after 8 years, from the millions of farmed adult fish to screen out more than 7,000 suitable for broodstock breeding groups. This group has become the world's largest group of broodstock, and the reserves of this broodstock group have made the basic storage for the explosive growth of China's Murray cod industry.

Since 2015, we have explored the research on the influence of external environmental factors on broodstock breeding and gonadal maturation, and in 2018, we basically figured out the influencing mechanism of temperature, light and nutritional conditions on broodstock gonad development, and successfully induced labor and breeding, but due to the timing of induction and other factors, only tens of thousands of fry were obtained, and the large-scale target was not reached.

In 2019, on the basis of the existing results, the scientific research team continued to conduct technical research on the monitoring of Murray cod gonadal development, the selection of oxytocin hormones, the timing of induction and the control of the oxytocind dose, the preservation and activation of Murray cod sperm, the fertilization method, the method of hanging the net of fertilized eggs, the technology of fertilized egg hatching and waterproof mold, the breeding conditions of hatched calves, the biotrophic enhancement of fry opening bait, the preparation of live bait re-intake feed, and the water quality management of the nursery process, and developed a set of technical process routes suitable for full artificial reproduction of Murray cod. In 2018, a total of about 4 million fertilized eggs, about 800,000 hatchlings, and more than 500,000 commercial fry with a body length of 3-5 cm were successfully bred for re-export feed, so far, the large-scale artificial nursery technology of Murray cod has been successful.

The Ministry of Education Science and Technology Innovation Workstation (L16) on the authoritative 24 databases to check the new confirmed that the Ocean University of China and Qingdao Qihao Biotechnology Co., Ltd., Qingdao Colorful Aoban Aquaculture Co., Ltd., Jiangsu Agricultural and Animal Husbandry Science and Technology College to carry out large-scale artificial breeding technology of Murray cod has been successful, the achievement of this industrialization technology for the world's first breakthrough, for Murray cod to further expand the scale of aquaculture industry laid a good technical foundation.

The scientific research team of ocean university of China and related partners will further improve the relevant technical routes and technical processes, rely on technological innovation and breeding of a huge group of broodstock, look for capital docking, and will create a billion yuan large-scale seed industry of Murray cod. In the next 1-2 years, strive to achieve the production of Murray cod fry to reach the order of millions, support the Murray cod breeding industry to reach a scale of 1,000 tons, the output value of the industrial chain to reach hundreds of millions to 1 billion yuan; in the next 3-5 years, the development of Murray cod fry production reached tens of millions of orders of magnitude, support the Murray cod breeding industry to reach a scale of 10,000 tons, the industrial chain output value reached billions of yuan; in the next 5-10 years, the development of Murray cod fry production reached 100 million tail level, Support the Murray cod aquaculture industry to reach a scale of more than 100,000 tons, and the output value of the industrial chain reaches a scale of billions to 10 billion yuan.