Artificial breeding of Chinese Sturgeon Gezhouba spawning Tianchi

Original title: past Life and present Life of "Patriotic Fish"

Unveil the mystery of artificial reproduction of Acipenser sinensis

On April 24, the Chinese Sturgeon attracted onlookers at the release site of rare fish on the Yangtze River in Yanzhi Garden, Yichang City, Hubei Province. Photo taken by Sun Ronggang

"he Zhizhang of the Tang Dynasty wrote about himself and the wandering son, but not about the Chinese Sturgeon." he Zhizhang, a Tang Dynasty, wrote about himself and his wandering son.

The Chinese Sturgeon, named after "China", was born in the middle and upper reaches of the Yangtze River and lives in the Yellow Sea and the East China Sea. Chen Lei, director of the Chinese Sturgeon Research Institute of the China three Gorges Group, said that when the Chinese Sturgeon matures at the age of 9-14, it can accurately find the Yangtze River Estuary on the vast sea, go up against the current in summer and autumn, and return to its birthplace to get married and have children.

What is also amazing is that in the year from entering the Yangtze River Estuary to leaving the Yangtze River and entering the sea, it was able to explore 3000 kilometers and find a place for cell clothes, showing an amazing character of enduring hunger and hard work. If you use human feelings to understand this kind of behavior, it is to bring life to the Yangtze River, but take almost nothing from the Yangtze River. Many people call it "returnee" and "patriotic fish".

As a central enterprise with the mission of "building the three Gorges and developing the Yangtze River", the three Gorges Group has invested more than 200 million yuan in the construction of ecological civilization on the Yangtze River to carry out scientific research and protection of Chinese Sturgeon, and has organized 58 release activities of Chinese Sturgeon. A total of more than 5 million Chinese Sturgeon were released, of which more than 17000 were artificially bred, effectively replenishing the species resources of the Chinese Sturgeon in the natural environment.

On April 24, the three Gorges Group invited volunteers from Yueyang and other cities along the Yangtze River to Yichang to release the Chinese Sturgeon. Sun Cheng, deputy general manager of the group, said affectionately: "I wish the Chinese Sturgeon released today a smooth return to the embrace of the sea, and wish them endless life in the mother river of the Yangtze River!"

"living fossil" is endangered, urgent!

Chinese Sturgeon, also known as mackerel, is the most primitive species of existing fish in the world, which can be called "fish living fossils". Over the past 140 million years, it has witnessed the prosperity and demise of dinosaurs and witnessed the formation and changes of the Yangtze River.

In ancient times, it did not call this ethnic name, "Erya" called it the yellow croaker. Chen Lei said that the Chinese Sturgeon is a large river-following migratory fish, unique to China, with the lowest latitude, largest size and fastest growth among more than 20 species of Sturgeon in the world. It is an important reference for the study of fish evolution. It has important scientific value and inestimable ecological, social and economic value in the study of biological evolution, geology, geomorphology, transgression, retrogression and other earth changes.

Due to various reasons, Chinese Sturgeon is on the verge of extinction. The protection of this "living fossil" is of far-reaching significance to the development and rational development and utilization of wildlife resources and the maintenance of ecological balance. In 1976, the state proposed the method of artificial proliferation and release to protect it. The commentator of the Exhibition Hall of the Chinese Sturgeon Research Institute told the reporter that many characteristics of the Chinese Sturgeon are somewhat similar to those of human beings. Its life expectancy is generally 70 or 80 years old, and those who live a long life can also live to 100 years old. In addition, the original spawning ground of the Chinese Sturgeon is in Yibin, Sichuan, which is his hometown. The small fish fry swam 3000 kilometers into the sea from there, and then more than a decade later, they can return to their hometown to give birth exactly. Is this very similar to human feelings for their hometown?.

Father Sturgeon "lives up to his fate", pain!

On January 4, 1981, the river of the Gezhouba Project was closed, and the road of the Chinese Sturgeon back to its hometown was blocked. It has been suggested that a fishway should be built on the Gezhouba hub to leave a way for the Chinese Sturgeon, but due to technical and financial limitations, decision makers choose to protect this species by artificial breeding.

In 1982, Gezhouba Fisheries Office, a professional institution for the protection of Chinese Sturgeon, was established in Yichang (renamed "Chinese Sturgeon Research Institute" in 1987), and protection work began immediately.

As the environment of the research pool is very different from the original spawning ground of the Jinsha River, the wild Chinese Sturgeon can only be artificially inseminated and artificially induced to give birth. Artificial induced labor requires induced labor materials, and the technique is to kill the male Chinese Sturgeon and take its pituitary gland to induce the birth of the female fish. Zhu Xin, former director of the breeding Center of the Chinese Sturgeon Research Institute, recalled: "it was very difficult for researchers to protect life by killing animals."

On April 24, the reporter saw at the release site that a large Chinese Sturgeon was released into the Yangtze River from the slide. In the 1980s, researchers poured 1cm-long fish fry into the river in a basin. Zhu Xin said: "under artificial conditions at that time, only 5% to 10% of the eggs laid by Chinese Sturgeon were able to produce 1 cm long 'spray'. If these 'spray' continue to be raised in the artificial environment of the institute, it is estimated that they will die out. They are thrown into the Yangtze River in the hope that they can survive in the natural environment. "

The Household Registration Book has been revised, hi!

There was a lot of pressure, and the researchers delved into it. In 1985, the Chinese Sturgeon Research Institute successfully used the self-developed synthetic hormone luteinizing hormone releasing hormone analogue (LRH-A) to replace the pituitary gland of male fish to induce labor, ending the tragic history of Chinese Sturgeon fathers exchanging their lives for their children.

Researchers have conducted in-depth studies on the impact of artificial environment on the growth of fish fry. "is the artificial environment easy to cause fish disease? How to improve the water quality? How to adjust the temperature? Even the details such as whether the bottom of the fish pond is too rough and bruised the abdominal skin of the Chinese Sturgeon have become the contents of the researchers' thinking and experiments. " Zhu Xin said, "now, all the adult fish are released more than 30 centimeters, which marks the maturity of a whole set of techniques for artificial breeding of Chinese Sturgeon, from catching parent fish to releasing fry."

There is also good news from nature: under Gezhouba, a natural spawning ground has been formed. It shows that the Chinese Sturgeon adapts to the environmental changes brought about by the river closure of Gezhouba Project. The hukou of Chinese Sturgeon has moved from Yibin, Sichuan to Yichang, Hubei.

The fact that the Chinese Sturgeon can gradually adapt to the Gezhouba project does not mean that it can accept the influence of all human activities. "in the early 1980s, we could observe that Chinese Sturgeon sperm had strong motility and rolled up and down; over the years, Chinese Sturgeon sperm could only move in a straight line in their semen." Zhu Xin said, "the pollution of the water quality of the Yangtze River will affect the reproduction of Chinese Sturgeon; the increase in the number of vessels and frequent fishing activities will also squeeze the space for Chinese Sturgeon activities."

In 1988, the Chinese Sturgeon was listed as a national first-class protected animal, and fishing is strictly prohibited. In 1996, it was listed in the Red Book of Endangered Animals by the World Union for Conservation of Nature. Gao Yong, deputy director of the Chinese Sturgeon Research Institute, called on: "the government, scientific research institutions, environmental protection organizations and citizens, especially the people along the Yangtze River, work together to prevent the Chinese Sturgeon from repeating the mistakes of the Baiji dolphin."

The "second generation" takes over, strong!

On October 4, 2009, the first fully artificially bred "second generation" Chinese Sturgeon emerged from the fertilized egg on October 4, 2009. In June of the following year, the first batch of "second generation" Chinese Sturgeon released the Yangtze River.

What is meant by "the second generation"? The researchers call the wild Chinese Sturgeon caught as "grandparents", and the generation produced by artificial breeding with them is called "father generation". The next generation of Chinese Sturgeon obtained by artificial reproduction of male and female fish is the "second generation".