Latin America Regional TCP Project on

Shrimp Health Management Ends





Rohana Subasinghe
Senior Fishery Resources Officer (Aquaculture)
Fisheries Department
FAO, Rome, Italy
rohana.subasinghe@fao.org

The FAO Regional Technical Cooperation Programme (TCP) Project on "Health Management in Shrimp Aquaculture in Latin America" ended successfully. The final field activity of the project, the third and final regional workshop on postlarval health, was held in Guayaquil, Ecuador in May 2003. The National Coordinators (NCs) from 13 regional countries finalized the regional hatchery technical standards for producing better health Penaeus vannamei postlarvae. Fourteen regional countries: Belize, Brazil, Colombia, Costa Rica, Cuba, Ecuador, El-Salvador, Guatemala, Honduras, Mexico, Nicaragua, Panama, Peru and Venezuela participated in the project, which began in 2001. At the inception workshop of the project, held in August 2001, representatives of each country (NCs) responded to a questionnaire on shrimp maturation and hatchery practices in their countries. The questionnaire covered a number of aspects of production, concentrating on maturation and hatchery types, sizes, species, management, physical and chemical treatments and disinfection procedures, health management, production and quality assessment methods, transportation methods, and problems encountered. This information, and the knowledge gained through a series of workshops and consultations held during the past two years that were attended by NCs, experts and industry representatives, provided the basis for the regional hatchery technical guidelines, which will be published late this year.

Aquaculture in Latin America

Total reported aquaculture production within the Latin American and Caribbean Region has increased over 714-fold by weight, from 1 221 metric tonnes (mt) in 1970 (0.03 percent of total global production) to 871 874 mt in 2000 (representing 1.9 percent of total global production). The annual percentage growth of the sector within the region has decreased from 34.4 percent per year (period 1970-1980) and 23.3 percent per year (period 1980-1990), to 14.2 percent per year (period 1990-2000), with the sector displaying an overall growth of 24.5 percent per year during the period 1970-2000. The total number of reported cultured species within the region has increased dramatically, from eight in 1970 to 46 in 2000. The main cultivated species groups in 2000 included finfish (624 thousand metric tonnes (tmt) or 71.6 percent), crustaceans (153 tmt or 17.6 percent), molluscs (60 tmt or 6.9 percent), aquatic plants (34 tmt or 3.8 percent) and amphibians (772 mt or 0.09 percent). The top ten cultured species by weight within the region in 2000 were Atlantic salmon (166 897 mt or 19.1 percent), whiteleg shrimp (139 264 mt or 16.0 percent), rainbow trout (97 479 mt or 11.2 percent), coho salmon (93 419 mt or 10.7 percent), tilapia (85 246 mt or 9.8 percent), common carp (62 241 mt or 7.1 percent), Gracilaria seaweed (33 642 mt or 3.8 percent), silver carp (30 000 mt or 3.4 percent), Chilean mussel (Mytilus chilensis) (23 477 mt or 2.7 percent) and the Peruvian calico scallop (Argopectinpurpuratus)(21 295 mt or 2.4 percent) (FAO, 2003).

By value, aquaculture production within the region has increased over eight-fold, from US$337 million in 1984 to US$2.98 thousand million in 2000 (representing 5.3 percent of the total global aquaculture production by value). The main species groups by value in 2000 were finfish (US$1.89 billion or 63.4 percent), crustaceans (US$0.94 billion or 31.5 percent) and molluscs (US$128 million or 4.3 percent). The top country producers by value within the region in 2000 included Chile (US$1.27 billion or 42.5 percent), Brazil (US$617 million or 20.7 percent), Ecuador (US$324 million or 10.8 percent), Colombia (US$258 million or 8.6 percent), Mexico (US$181 million or 7.0 percent), Honduras (US$59 million or 2.0 percent), Cuba (US$47 million or 1.6 percent), Venezuela (US$43 million or 1.1 percent). Costa Rica (US$33 million or 1.4 percent) and Peru (US$ 28 million or 0.9 percent) (FAO, 2003).

Shrimp Culture in the Region

The shrimp farming industry in Latin America has emerged as one of the major foreign exchange earners in the region. However, disease has become a major constraint; especially since the outbreak of white spot disease (WSD), shrimp production has decreased significantly in many countries and farmers are facing serious difficulties in continuing production. The resulting economic losses and their impacts are now significantly affecting national economies and the livelihoods of poorer sectors. For example, the shrimp exports from Ecuador in December 1999 fell to below 1985 levels.

Initially, shrimp producers relied almost entirely upon the capture of wild postlarvae (PL) in the estuaries and coastal areas where these are found naturally. Seasonal and annual variations in the catch of PL, however, led to the development of hatcheries where shrimp PL production could be undertaken in a more controlled manner. These hatcheries used wild broodstock that were caught and supplied by fishermen.

The fluctuations in catches of both wild PL and broodstock as a result of the El Niņo phenomenon had a major impact on the development of hatcheries. In years when wild seed was abundant, low prices for PL and a general perception that wild seed was stronger meant that many hatcheries encountered financial difficulties. In years when wild seed was scarce, on the other hand, hatchery-produced seed could be sold at a premium. Despite this, many hatcheries experienced problems due to the unpredictability of the market situation.

Shrimp Health Problems

In recent years, disease, or more specifically, shrimp health concerns, led to a revival of interest in hatchery-produced PL. Shrimp from Panamanian waters were widely believed to be less sensitive to taura syndrome virus (TSV) than those from other areas, and this led to a lucrative trade in broodstock, nauplii and PL from Panama to other countries in the region and between countries producing from these stocks. Unfortunately, the arrival of the white spot syndrome virus (WSSV) in the region in the late 1990s exposed the local hatchery operators to the possibility that the disease might be spread by such transfers if they were not accomplished using appropriate controls and regulation.

At the same time, several producers had been experimenting with the breeding of survivors of TSV outbreaks in an attempt to develop lines of shrimp with greater resistance to the virus. The WSSV epidemic and the risk of vertical transmission accelerated this and led to a greater interest in genetics and breeding and a recognition that the dependence on wild sources of shrimp represented a significant disease risk. Hatchery operators reviewed their operations and focused on improving the biosecurity and health management of their production systems.

The simplest way to solve the PL quality problem is to change from the use of PL derived from captured broodstock to PL derived from domesticated stocks. However, this practice requires considerable research effort and field-testing, and is still in its infancy. At least we can try to ensure biosecurity in ponds through appropriate screening of PL for important pathogens prior to stocking. The procedures for screening PL for important pathogens (currently predominantly the WSSV) are known; however, some training, capacity building and upgrading of hatcheries and diagnostic centres are necessary.

Currently, there are little or no harmonized (technical) standards on hatchery production of PL. It is imperative that such technical standards are developed, validated, standardized and agreed upon by the hatchery producers, both nationally and internationally.

Most countries in Latin America have begun domestication and genetic selection programmes using pond-reared broodstock in maturation systems. This has been done in an attempt to stabilize predictability and to improve the disease resistance and growth rate of their shrimp stocks. Initial efforts used broodstock from a variety of countries around the region in order to ensure a wide genetic variability in the stocks, but subsequent closure of most borders to import of live shrimp has curtailed this activity.

Most countries in the region are concentrating on the production of specific pathogen resistant (SPR) shrimp, selecting the best surviving (but not necessarily disease-free) animals from pond on-growing facilities and on-growing them further in various facilities before transfer to maturation systems. Specific pathogen free (SPF) shrimp (shrimp certified free from a specified serious disease or diseases and held throughout their lives in closed systems) have also been used, but with less frequency. Where used, these animals have generally been brought in from isolated breeding centres in the United States.

FAO Assistance

In November 1999, an FAO Expert Workshop was held in Cebu, Philippines, where 14 shrimp-producing countries, including five from Latin America, attended. The workshop discussed the strategies for controlling shrimp disease problems globally and recommended future activities. These ideas were further discussed at the APEC/NACA/FAO/SEMERNAP Expert Workshop on Trans-boundary Aquatic Animal Pathogen Transfer and the Development of Harmonized Standards on Aquaculture Health Management, which was held in Puerto Vallarta, Jalisco, Mexico, from 24th-28th July 2000. Consensus has been built that the above ideas should be incorporated into an FAO Regional Technical Cooperation Project aimed at assisting member countries, particularly those in Latin America.

National coordinators from 13 countries in Latin America who participated in the final workshop in Guayaquil, Ecuador

In early 2001, the Government of Ecuador made a formal request to FAO for technical assistance to combat serious shrimp disease problems in Ecuador. FAO, in consultation and agreement with the other shrimp-producing countries in the Americas, decided to prepare a Regional TCP Project to provide technical assistance to the shrimp health problem in the region. The development objectives of the project were to secure and increase the income of the shrimp farmers in Latin America by improving national income, food security status and rural livelihoods by minimizing outbreaks of disease in shrimp aquaculture. The project attempted to achieve this objective through:

  • Developing a programme for improving health, sanitary status and quality of hatchery-produced shrimp PL, in particular, by compiling hatchery technical standards for producing better health Penaeus vannamei PL;
  • Improving farmer capacity in disease control and health management in shrimp aquaculture; and
  • Developing and establishing an information system on aquatic animal health, with a view to providing vital information required during the movement of live aquatic animals, with special reference to reducing transboundary pathogen movement.

The project field activities included four regional workshops on shrimp health and two regional laboratory training workshops on shrimp disease diagnostics. The regional hatchery technical standards are being finalized for printing, and the Latin American Chapter of the FAO Aquatic Animal Pathogen and Quarantine Information System (AAPQIS) will soon be fully functional and available to the public. It is hoped that the regional technical standards will help regional hatchery operators to improve their management practices and the regional governments to develop the policy and regulatory measures necessary to improve the overall quality of the PL produced, thus improving regional shrimp production and maintaining sectoral sustainability.

References

FAO. 2003. Review of the state of world aquaculture. FAO Fisheries Circular No. 886, Rev. 2. FAO, Rome, 95 pp.