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Genetically improved farmed tilapia (GIFT) fish strains aim to help make small-scale fish farms in China more profitable, and the success of the effort will depend on carefully planned and implemented fingerling distribution
China is the largest producer of fish in the world. This may not come as a surprise, as China is huge, with 14,500 kilometers of coastline and a population in excess of 1.3 billion with a particular fondness for eating the “fruits of the sea” — or the pond for that matter.
Catching fish from the sea used to be the mainstay of China’s important fishery industry. In the 1950s and 1960s, China’s annual marine fishing production was made up mainly of commercially important bottom-dwelling species. Since then, however, this fishery has suffered from the same challenges that face other marine fisheries around the world. Production levels are static, and the catch is increasingly composed of younger, smaller individuals and of lower-value open-water species — the results of overfishing as well as the effects of localized coastal pollution.
But not all fish is caught in lakes or oceans. A growing proportion is farmed. The history of fish farming in China goes back at least 2,500 years, and the practice has a time-honored status in the rich traditions of China. Only in recent years, though, has it reached anything like its current prominence. In 1999, in view of the dismal state of the marine fisheries, the Chinese government implemented a policy of zero growth for production from the sea. In response, production from aquaculture exploded, having grown by the following year to exceed 25 million tons and provide 60% of the country’s total fisheries output. Pond culture is the most important and widely practiced system, supplying 60-70% of total freshwater production. A range of carp species are the most favored, though species introduced from abroad, such as tilapia and catfish, also feature in the market. Several different farming practices are used: polyculture, or growing several different species of carp together, each with slightly different needs and diets; integrated farming systems in which fish are grown with crops such as flooded rice or aquatic plants; and intensive culture systems involving special feeds, dedicated water-quality management, disease control and hatchery management.
Yields have risen dramatically, the area of land used for aquaculture has mushroomed, and the industry has created many new employment opportunities. However, there are constraints to growth. Agricultural land per capita in China is decreasing, there is a shortage of freshwater in the country overall, and environmentally sustainable production systems are needed that maximize farmers’ yield.
Most fish culture in China still depends on wild seed stocks. Back on the farm — conventional agriculture as we understand it — the production of terrestrial animal species such as dairy cattle, pigs and poultry has blossomed as a result of selective breeding programs. These involve choosing the individual animals that demonstrate the most promising characteristics, such as faster growth or greater milk production, and using them as the parents of the next generation — artificial selection rather than natural selection. Some improvements in productivity were made in carp species in the 1960s and 1970s through selective breeding, but genetic gains were often lost when farmers allowed their fish to breed with wild individuals.
In 1988, a project was established by a research Center supported by the CGIAR to breed an improved strain of Nile tilapia (Oreochromis niloticus). By collecting eight strains of tilapia — Egypt, Senegal, Ghana, Kenya. Israel, Singapore, Taiwan and Thailand — and carrying out multiple crosses, a broad genetic base was assured before selection was initiated. The fish were selectively bred to enhance their growth and survival rate. The resulting strain showed an 85% gain in growth rate relative to the base population from which it began and remarkable survival rates. This became known as genetically improved farmed tilapia, or GIFT.
The GIFT strain has the potential to lower costs and increase fish production and consumption, thereby improving the overall nutritional status of the population. The work was proved successful, and the CGIAR Standing Council on Impact Assessment cited it as an example of best practice, as it has contributed significantly to improving livelihoods for disadvantaged fish farmers.
The project provided GIFT fingerlings in the Philippines (where is has become the first choice of fish farmers), Bangladesh, Thailand, Vietnam, China and six other countries in Asia and the Pacific. In all countries, the GIFT strain has shown an improved yield over those previously utilized and generated higher incomes for the farmers. The gains have not, however, been evenly balanced across all countries in all farming situations. For example, the yield gain from growth in ponds in the Philippines was 54%, in Bangladesh 78%, in Thailand 38% and in Vietnam 33% — but in China only 9%.
In China, where the GIFT strain was introduced from the Philippines in the early 1990s, the on-farm performance was consistently better than national strains in cages (with a 25% gain) and tanks (a 29% gain) but only marginally better in ponds (a 4-16% gain).Its survival rates in ponds has been slightly lower than those of national strains. However, work on GIFT tilapia has not stood still, and the potential for better returns still exists. In 2006, a further improved line of GIFT was introduced into China, and a selective breeding program was established locally with the Chinese Academy of Fisheries in Wuxi, Jiangsu Province.
Dr. Xu Pao, director of the Freshwater Fisheries Research Center in Wuxi, says that he and his staff work together closely with farmers to understand their problems and needs.
“Sometimes we’re scholars and sometimes we’re farmers,” he says smiling broadly, before detailing what is required from the latest strain of tilapia. “The growth performance has to be very good. It should have a good resistance to disease, and it should have more meat content.
“We want to help the farmer earn more money by using our technology,” he adds.
Xu points out that farmers are reluctant to try new technologies, and so a way must be found to convince them. He says the best way to do this is by proving the effectiveness of the new strain.
“If the farmers don’t earn more money by the end of the year,” he observes, “they won’t accept your ideas.”
In this new phase of development, the key to unlocking the full genetic potential of the tilapia is to select for individuals that show both the improved productivity of the strain and are also well adapted to the local climatic and environmental conditions that exist in China. The fact is that tilapia, a native of Africa, may find Chinese winters a little too chilly. Although GIFT will not necessarily provide the answer to aquaculture needs in all the climatic regions of China, it is certainly capable of making a very useful contribution to the efficiency of production in many of them.
But there is many a slip twixt cup and lip, to quote an old English proverb, and it is not just the science that matters to the farmer who grows the fish. The dissemination and authenticity of the improved broodstock is crucial to both the farmer and the consumer. GIFT fish have acquired a special reputation, and it is all too easy for a less-than-scrupulous fingerling salesman to pass off his baby fish as GIFT without the hapless farmer being aware of their true genetic identity.
To muddy the waters still further, there is more than one GIFT-derived strain of tilapia circulating in the Chinese marketplace. For the farmer, this can cause confusion and sometimes disappointment when the fingerlings he buys do not deliver the results that he anticipated. One of the lessons being learned from researchers in the field is that an excellent product must be supported by an accredited distribution system to avoid misrepresentation and heartbreak.
“A lot of the movement of fish in China is uncontrollable,” says Malcolm Beveridge, a CGIAR scientist and specialist in aquaculture and genetics. “It’s the same in all the countries that I've been to. How does the farmer know what he’s buying? There has to be some sort of accreditation system.”
“This underscores the importance of setting up an effective breeding system in the country to control the management of the breeding population, and to ensure an effective seed distribution system so farmers can benefit from these genetic improvements,” Beveridge says, adding that, so far, this has been achieved in only a few countries. He is optimistic that this can be achieved in China.
Building on their successes in other Asian countries, CGIAR aquaculture scientists and their partners in China are leading the next step in aquaculture production by improving the productivity of both tilapia and carp. China is huge, covering a vast array of climatic zones, so selective breeding will be required to produce the optimal varieties for a range of different locations, environmental conditions and farming practices.
The strengthened partnership between the Chinese Academy of Sciences and the CGIAR is poised to have a spectacular impact on the country’s aquaculture and to lead the next explosive rise in fish produced in China.
Meanwhile, a new laboratory for developing animal genetic resources, jointed managed in suburban Beijing by Chinese and CGIAR partners, aims to develop a certification system for valuable native breeds of livestock and poultry to earn higher profits for farmers and assure consumers that they are getting what they pay for.
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