The American state of California is famous for its agriculture.Now, scientists are working to make California a world leader in theproduction of caviar. Caviar is made from the eggs of the large fishcalled sturgeon. Caviar is a popular and very costly food in manyparts of the world.
The University of California atDavis reports that California is already the world’s leadingproducer of white sturgeon. It says the state’s success is partlythe result of work by one of its professors.
Serge Doroshov (surgeDOOR-uh-shof) joined the university’s animal science departmenttwenty-five years ago. He and his team showed that it is possible tospeed up the rate at which sturgeon develop sexually. To do this,they successfully changed the environment where the fish develop.They also used hormones to influence the production of eggs and malereproductive fluid.
Sturgeon and their ancestors are thought to have lived as longago as two-hundred-million years. That is long before the appearanceof most modern fish. Sturgeon have long, thin bodies covered with aseries of bony plates. The head is also well protected with thesehard structures.
Sturgeon can live for more than one-hundred years. Some weighmore than four-hundred-fifty kilograms. However, the fish developslowly. Females in the wild are not able to reproduce until they arefifteen to twenty-five years old.
Most sturgeon move from salt water into inland waterways whenthey are ready to reproduce. However, some live permanently in freshwaters.
Sturgeon were once common in North America. However, too muchfishing, building projects and pollution have greatly reduced theirnumber. Today, Iran and Russia produce most of the world’s caviarfrom sturgeon. The most valuable caviar comes from a kind ofsturgeon called beluga (ba-LOO-ga).
Professor Doroshov showed that sturgeon could be raised in smallbodies of water and large containers. He also showed that the fishwill eat food not found in their natural environment. He and otherscientists are now attempting to grow bigger, longer-living sturgeonthat produce large amounts of caviar.
Professor Doroshov has also helped develop methods to raise otherkinds of fish.
This VOA Special English AGRICULTURE REPORT was written by GeorgeGrow.