Tilapia farming in China

As one of the four SEAT subject species and countries, tilapia production in China has been thoroughly investigated throughout the project. The research has found many positive attributes of this fish and the systems in which it is produced and this research has been collated to give an overview of Chinese tilapia here.

Tilapia’s contested rise

Since the early 2000s, tilapia has undergone a meteoric rise and by 2010 had become the fourth most commonly consumed seafood in the USA. High quality tilapia has been available for a number of years in supermarkets across Europe and was promoted as a sustainable seafood choice at the London Olympics. Although consumption in Europe remains low, it has many of the attributes that both retailers and consumers want in fish and its popularity looks set to grow even though criticism of such imported farmed fish has been particularly prominent across the internet. While there is a vocal online presence claiming tilapias are “garbage fish” raised in unsanitary conditions in Asia, other internet-sources laud the ‘green‘ virtues of the fish as well as its now global production and value chain which provides not just food but incomes and employment for hundreds of thousands of people.. These green credentials relate to tilapia’s efficient conversion of feeds that contain little or no fishmeal into higher quality protein, and make it a good choice for environmentally aware consumers as well as benefitting farmers (among others) in developing countries.

Tilapia & SEAT

Tilapia is one of the SEAT focus species, and is farmed in significant qualities in all four countries (China, Thailand, Vietnam and Bangladesh) where research is underway. China is both the World’s biggest producer of farmed tilapia (40% of total production) but also dominates global trade. Thailand also has a prominent industry supplying its domestic market and its production (and ambitions) are at a point where exports and international market position seem set to increase.

Addressing criticisms

Much of the criticism aimed at the tilapia farmed in Asia concentrates on perceived poor water quality and risks to public health. Both Thai and Chinese producers are very aware of the importance in ensuring farming meets best practice. SEAT surveys found that Thai and Chinese farmers ranked, these issues in the top three of all factors affecting them and the sustainabilities of their businesses.

Four key measures of water quality (dissolved oxygen levels, total suspended solids and Nitrogen and Phosphorus levels) were recently assessed through SEAT in a variety of farms in both China and Thailand. In both countries, average water quality between the different farms showed encouraging results. The Thai farms met the Global Aquaculture Alliance, Best Aquaculture Practice standards for all of the measures except total Phosphorous, and in China all except total suspended solids passed BAP limits (Munro et al., in press)[1].

Farm management in both Thailand and China has been shown to greatly reduce the risk of parasitic infections by zoonotic trematodes. The management measures mean that the farmed tilapia, are less likely to suffer infections than local wild fish (Li et al 2013, Wiraya et al, 2013). These parasites, zoonotic trematodes (such as Chinese liver flukes), can have serious health implications for people eating infected fresh fish. But, for European and American consumers, the food safety risks related to fish-borne zoonotic trematodes from Asia are very low. Most of the tilapia exported to Europe is frozen during processing which is fatal to the parasites and eliminates risk of human infection [2]. It has also been noted in another SEAT study that potentially harmful bacteria in imported seafood are more likely to originate during processing or reprocessing in Europe than from the original  fish pond production.

Another stick used to beat tilapia has been that various chemicals including antibiotics are overused within the production sectors in China and Thailand.  SEAT Field research however, suggests this is not the case.. Less than 20% of the surveyed Chinese and 10% of Thai farms reported use of antibiotics, this can be compared with 100% of Vietnamese Pangasius farmers in a similar study. The rates of chemical inputs are higher in the larger Chinese farms but even these are lower than Atlantic salmon from Chile and most terrestrial livestock. In fact, researchers involved concluded that under-dosing (with the potential risk of subsequent antibiotic resistance developing) may, in fact be more of an issue.

In most cases, single, generic criticisms aimed at an entire industry are unlikely to be accurate. This is especially true in Chinese tilapia production where farmers use a wide variety of management approaches. Although Chinese production is mainly pond based, farms can be such that production is almost completely dependent on formulated feeds whereas others use no feeds at all, instead relying on naturally occurring nutrients within the systems. Both production and exports have grown rapidly in China and as its market position has strengthened, the amount of misinformation has also increased. Much of the Chinese production remains within the country to satisfy its domestic markets, producers wishing to export to foreign markets must register their farms with the Chinese Inspection and Quarantine (CIQ) Bureau who are responsible for export standards. As the majority of producers in China are not CIQ registered, they are therefore not able to export their products. A high proportion of registered farms are either larger pond farms or raise tilapia in leased reservoirs. These farms tend to have high production and specifically focus on export markets. As part of their registration, in order to be able to export their products, these farms are subject to stricter standards and inspections. Once or twice a year, at random, CIQ inspectors visit the farms. The inspectors check for illegal chemicals, feeds and investigate the environment at the farm site. As well as the on site investigations, samples of the fish and water are also collected and taken back to be checked at the CIQ’s own laboratories.

‘Feeding on faeces’?

Use of livestock manure to fertilise fish ponds is still common in China but has become strictly limited to farms selling to the domestic market. Manures work in the same way as in terrestrial farms. Nutrients from the manure are absorbed by the plant (plankton), which is consumed by the fish in the same way that cattle graze on pasture. At low fish densities this availability of natural feed can reduce the amount of fish feed the farmer has to use and reduce costs. But for farmers producing more intensively for export markets, the use of manures become irrelevant as almost all of the nutrition is supplied in a formulated diet and any manure added would just cause poor water quality and slower fish growth. Hence a US Food and Drug Agency (FDA) spokesperson’s comment that there was “no evidence to support the claim that tilapia raised for export were fed manure in China”

Global feeds for a global food

There are a wide variety of alternative feeding methods and ingredients that can be, and are, used to produce tilapia. These include fishmeal, blood meal (usually from swine), rice bran and soy. Compared to many of the animal-derived alternatives, soy usually has lower environmental impacts (with regards to greenhouse gasses and risk of eutrophication; Henriksson, 2013). Chinese tilapia production uses a lot of soy, with an estimated  50,000 MT of soy contributing to creating 100,000 MT of tilapia fillets for export. Chinese aquaculture is certainly an important market for American soy producers as China is the dominant importer of USA produced soy. Imports in 2012-13 were valued at $13 billion (approximately 25% of exported US soy) and is forecast to increase by 17% in 2013-14. The use of US grown soy to produce Chinese tilapia, which are then exported to the USA perfectly demonstrates the interconnectedness of this international trade.

Is there a problem?

One of the biggest challenges that both Chinese and Thai tilapia producers face in ensuring sustainability is that of off-flavour at consumption. Such muddy flavoured fish are safe for human consumption, but the unpleasant taste is damaging for the product’s reputation and helps negative perceptions spread. This problem is not limited to tilapia (also occurring in products such as milk and wine) and simple quality control processes are known to control the problem. The SEAT project is urging those involved to act at introducing such procedures that have a proven track record in avoiding off flavoured fish reaching markets and damaging reputations.

In the future, competition between local and export demands is likely to intensify, but meeting local food security can be compatible with export trade. Investigating the whole value chains in these Asian countries for multiple aspects of “sustainability” have shown that tilapia can offer a low footprint and highly beneficial food product.

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[1] Values show averages from 3 repeated tests of 6 farms in both Thailand and China (Munro et al., in press).

Dissolved Oxygen(mg/l) Total Nitrogen(mg/l) Total Phosphorous(mg/l) Total Suspended Solids (mg/l)
BAP standards

>4

<5

<0.5

<100

China

6.3

1.98

0.35

124.2

Thailand

9.13

4.5

0.75

42.1

[2] According to the US FDA, freezing and storing at – 0°C or below for 7 days (total time), or freezing at -35oC or below until frozen solid and storing at -35°C or below for 15 hours, or freezing at -35°C or below until frozen solid and storing at -20°C or below for 24 hours is sufficient to kill the parasites.

Photo © Loni Hensler