A Market Study of Specific Pathogen-Free Shrimp
by Andrew M. Kuljis and Dr. Christopher L. Brown*
*SPF Project Leader

Center for Tropical and Subtropical Aquaculture Publication No. 112

I. Executive Summary

During the 1980's, shrimp farming underwent a major expansion in each of the four countries in this study: Ecuador, the Philippines, Thailand and Indonesia. In each study country, production continues to increase in the 1990s, although at a slower pace. All of the study countries are experiencing problems with disease. The cost of shrimp farm operations is increasing due to the expense of combating disease problems. At the same time, world market prices for shrimp are either remaining stable or declining. The result is that shrimp farmers are being financially squeezed. Indications are that specific pathogen-free (SPF), or IHHN virus-free, P. vannamei will be well accepted in Ecuador because SPF stocks have been demonstrated to be effective against the runt deformity syndrome. The captive maturation infrastructure required to propagate these stocks is already in place, and the demonstrated efficacy of these stocks will result in higher yields and higher value crops. In addition, the ability to produce a continuous, year-round supply of high quality nauplii will increase the efficiency of both Ecuador's hatchery and growout sectors and result in lower costs and higher profit margins for shrimp farmers. Speculating on the market for SPF P. monodon in southeast Asia proves more difficult. SPF P. monodon have not yet been studied under production conditions, and the impact of the MBV virus and the IHHN virus on shrimp production of P. monodon is not yet clear. Shrimp farmers in southeast Asia have shown an interest in pursuing the development of an SPF P. monodon stock. Hatchery operators who sell SPF postlarvae will likely have a market advantage because, given the choice, growers probably would purchase SPF postlarvae as long the price were competitive. The long-term viability and market value of SPF P. monodon postlarvae will be determined by their performance in commercial production. Therefore, the process of identifying and isolating SPF P. monodon broodstock should begin as soon as possible so that their performance in commercial production systems can be evaluated.

II.Introduction

Objective of the Study

The specific pathogen-free shrimp (SPF) market study is intended to: assess the potential market for specific pathogen free broodstock, nauplii and postlarvae in Ecuador, the Philippines, Thailand, and Indonesia; assess the current prices paid for broodstock, nauplii and postlarvae in the study countries; determine if there are trends in the current culture practices of thestudy countries that indicate whether SPF stocks would be valued by commercial producers. Figures 1 and 2 show the results of 1991 world shrimp farm heads-on production.

Countries Selected for This Study

Ecuador, the Philippines, Thailand and Indonesia were chosen for this study because they lead the world in terms of the level of shrimp culture technology practiced. In 1991, the shrimp aquaculture production from these countries totaled approximately 350,000 metric tons (MT), which is more than half of the total shrimp produced from aquaculture in the world. These countries have made a major commitment to the production of postlarvae from hatcheries, and all have experienced production problems that were caused by either animal quality or disease. All of the study countries have well developed, fully integrated shrimp farming sectors with the technological capability to incorporate a program of SPF culture readily into their shrimp culture systems. In addition, all of the study countries have free access to foreign currency and, pending government approval, would be able to purchase and import SPF stocks if such stocks became readily available.

Rationale

Disease problems are increasing in every major shrimp farming area of the world. Even wild populations in shrimp farming areas are showing increased levels of certain pathogenic viruses and bacteria. Current disease problems on shrimp farms are widely believed to be at least partially the result of contamination of wild populations, which are used as the primary source of broodstock for the shrimp farming industry. The incidence of disease problems on shrimp farms is escalating. Bacteria and viruses that have been identified as shrimp pathogens are spreading, and new diseases are continually being identified. Efforts to combat disease problems have increased operating costs and have led to reduced profits or, in many cases, losses to shrimp farmers. In Hawaii and in the U.S. Mainland, specific pathogen-free stocks of Penaeus vannamei have demonstrated improved production performance when compared to stocks contaminated with the IHHN virus (Wyban 1992, Carpenter 1992). To date, it has not been shown that the same response will be achieved with P. monodon. The specific pathogen-free (SPF) program is based upon guidelines for working with exotic species that were developed by the International Council for Exploration of the Seas (ICES) in 1988. Only disease-causing microbes that can be reliably diagnosed and physically excluded from a facility can be considered in an SPF program. The certifiable pathogens for P. vannamei are listed in Table 1. Note that the SPF definition for P. monodon has not been developed. Prior to this study, shrimp stocks certified to be specific pathogen-free have never been available in the study countries, and assessing the market potential for these products is difficult without comparative performance data between infected and uninfected stocks. Such studies are only now being undertaken in these countries. However, SPF broodstock, nauplii, and postlarvae have been marketed in the United States and Mexico, and a market exists for shrimp broodstock, nauplii and postlarvae in all of the study countries. Therefore, it is believed that a study of the existing markets in these countries will identify certain practices, preferences and trends in the market that will indicate whether the shrimp farming industry will accept and value SPF broodstock, nauplii and postlarvae. In each study country, differences are perceived in broodstock, nauplii, and postlarvae quality that relate directly to production performance. In Ecuador, for example, wild spawners are preferred over captive spawners. Nauplii from wild spawners are preferred over nauplii from captive spawners, and wild postlarvae are preferred over hatchery-reared postlarvae. The least desirable are those postlarvae produced from captive maturation. The construction of hatcheries began because the industry expanded in the 1980s beyond the availability of wild postlarvae. The extent of the supply of wild postlarvae fluctuates widely with weather cycles and seasons. In 1992, concerns about the quality and performance of wild postlarvae began to surface. Similar circumstances occur in Southeast Asia, where the source of spawners is considered very important. Spawners from areas that are perceived to be desirable bring a much higher price than spawners from less desirable areas. Extending performance data from one species to another must be undertaken with caution. Controlled studies do not exist; therefore, other criteria must be used. The reputation of a hatchery depends on the performance of its postlarvae in production ponds. A hatchery with a consistent record of producing high performance postlarvae will command prices up to 30 percent higher for its postlarvae than other hatcheries in the market. The financial success of a program to produce specific pathogen-free stocks for sale to producers will depend on how well these stocks perform in the production systems of the major shrimp producing countries.

III. Shrimp Aquaculture Development in Ecuador,the Philippines, Thailand andIndonesia Ecuador

Ecuador (Map 1) is the largest producer and exporter of shrimp in the Western Hemisphere (Rosenberry 1991). In the 1970s, Ecuador's production of shrimp came primarily from trawling. The trawler industry continues to capture and export approximately 2,000 to 5,000 MT of processed shrimp per year. In the late 1970s, investment in shrimp farming began to contribute to the export total. By 1981, the amount of shrimp exported reached 13,000 MT due to the contribution of cultured shrimp. Since 1981, shrimp aquaculture production has increased at a relatively steady pace (Table 2). In 1991, total weight farm production of shrimp exceeded 100,000 MT (Rosenberry 1991), and the value exceeded $400,000 million. The principal species produced on shrimp farms in Ecuador is the white shrimp, P. vannamei. In 1991, in excess of 160,000 hectares (Rosenberry 1991) of ponds were estimated to have been developed for the production of shrimp. As of 1990, 125,000 hectares have been legally registered with the Ecuadorian government. All four coastal provinces of Ecuador have shrimp farms. The largest concentration of shrimp farms, comprising about 70 percent of the total area, is in the province of Guayas. Most of these farms were constructed on the Guayas estuary and used virtually all of the available land on both banks of the Guayas river delta. The majority of shrimp farms are less than 50 hectares in area, although some large commercial farms in excess of 2,000 hectares exist. (Table 3).

Aquaculture Practices

Because Ecuador is on the equator, ocean currents greatly affect its climate. As with other agriculture activities, shrimp culture practices are strongly influenced by climate. A general ocean warming begins off southern Ecuador in December. That warming coincides with the beginning of the rainy season, which lasts until April. During the rainy season, spawners are abundant off the south coast of Ecuador near San Pablo, and wild postlarvae are available in the Guayas Estuary. During this period, farmers traditionally stock their ponds using wild postlarvae resources. With careful planning and some luck, two crops can be produced from the supply of wild postlarvae. The first crop begins in December and is harvested in May. The second crop is produced during June through November. Since wild postlarvae are sometimes not available after June, wild postlarvae are collected in March, April and May and held in nursery ponds at relatively high concentrations until the first crop of growout ponds is harvested. Approximately 10 percent of the production area of the typical shrimp farm in Ecuador is devoted to nursery ponds. Nursery ponds are generally less than one hectare, but growout ponds in Ecuador average 10 hectares. The development of hatcheries began in the early 1980s. By 1986, production strategy had undergone a major shift toward intensification due to the increased availability of postlarvae from hatcheries. Many of the farms increased their stocking densities from 5 to 6 shrimp per square meter to 10 to 12 shrimp per square meter. Year-round production of postlarvae from hatcheries became possible due to the discovery of a second season for obtaining spawners from the north in Esmeraldas. This season begins in June; spawners generally continue to be available until November. Shrimp farming in Ecuador remains, for the most part, extensive. In 1991, average production per hectare, in two crops, was approximately 650 kg per year. Using hatchery postlarvae and current water management and feed technology, higher intensity farms that stock 10 to 12 shrimp per square meter produce 3,000 kg per hectare yearly.

Hatcheries

Currently, well over 300 shrimp hatcheries operate in Ecuador; 117 of those were officially registered with the Ecuadorian government as of 1990. The introduction of hatchery technology has dramatically changed the availability of postlarvae in that country. Currently, almost 60 percent of the postlarvae used in Ecuadorian shrimp farms come mostly from wild spawners in hatcheries. The remaining 40 percent are wild postlarvae from the Guayas estuary. Wild postlarvae proved particularly abundant in 1992, due primarily to the presence of the el Nino weather phenomenon. In some years the availability of wild postlarvae is limited, and hatcheries may contribute up to 80 percent of postlarvae. Hatcheries have enabled Ecuador to increase overall production of shrimp by ensuring shrimp farmers a more consistent supply of postlarvae than is available from the estuary. However, because hatcheries depend on the capture of wild spawners, at times postlarvae are in short supply. In a typical year (if such a thing exists) spawners may be in short supply from March through May, which are transition months between the availability of spawners in San Pablo and availability of spawners in Esmeraldas. Additionally, in some years the spawner supply is limited during months when it is typically abundant. The year-to-year uncertainty of the spawner supply led to a major investment in the development of captive maturation facilities, which began in the mid 1980s. Not until 1987 did the impact of the IHHN virus begin to be realized. The presence of the IHHN virus in cultured stocks causes a runt deformity syndrome (RDS), in which a substantial percentage of the animals grow at reduced rates and are smaller than the average size shrimp in the pond at harvest. The severity of RDS appears to be directly related to the level of IHHN virus infestation. It soon became apparent that shrimp produced from captive maturation exhibited a higher degree of RDS than those produced from wild spawners. This presumably was because the level of IHHN virus infection in the wild population was relatively low, and when these wild stocks were held in captivity, the virus quickly spread from infected to uninfected broodstock. Therefore, captive stocks exhibit a much higher rate of infection. The difference in pond performance between postlarvae produced from wild spawners and those produced from captive maturation is said to be approximately 15 percent. This 15 percent loss in production can be attributed directly to the production of postlarvae from captive maturation when the IHHN virus is present.

Postlarvae

In 1991, farms in Ecuador required a total of 15 billion postlarvae, approximately 9 billion of which were produced in hatcheries and 6 billion of which were captured. Hatchery technology has come a long way toward providing a consistent supply of high quality postlarvae to the Ecuadorian shrimp farming industry. Unfortunately, the presence of the IHHN virus in Ecuadorian shrimp stocks has compromised the quality of hatchery-produced postlarvae. Ecuadorian shrimp farmers can measure the loss in performance due to reduced postlarvae quality and will pay higher prices for wild postlarvae and postlarvae produced from wild spawners than for postlarvae produced from captive maturation. Currently, postlarvae sell for three prices in Ecuador. Wild postlarvae sell for approximately $5.40 per 1,000; hatchery-produced postlarvae from wild spawners sell for approximately $3.85 per 1,000; and hatchery produced postlarvae from captive maturation sell for approximately $2.70 per 1,000. When wild spawners are readily available, most growers will not use postlarvae produced from maturation, although the animals are much cheaper. However, rather than leaving ponds unstocked, most growers will stock their ponds with maturation postlarvae when postlarvae produced from wild spawners are unavailable. During such times, prices for maturation-produced postlarvae will increase to approximately that of postlarvae produced from wild spawners.

Nauplii

Assuming that survival of nauplii to postlarvae in hatcheries is approximately 50 percent as a country-wide average, Ecuador's requirement for nauplii is approximately 18 billion. Because nauplii are primarily obtained from wild spawners, the cost of wild nauplii will fluctuate depending on the availability of wild spawners and the demand for nauplii. Typically, nauplii prices are highest from March through May when wild spawners are least available. The price of wild nauplii will not only fluctuate greatly throughout the year but also from year to year. At this writing, the price for wild nauplii approximately $0.43 per 1,000 is at its lowest level in 5 years. Amorient Aquafarm paid an average price of approximately $0.95 per 1,000 for wild nauplii over the past 5 years. However, due to the recent downward trend in the world market for shrimp and its impact on all aspects of shrimp production, the price for wild nauplii is unlikely to increase to more than $0.75 per 1,000 in the near future.

Broodstock

The number of broodstock required will depend on whether they are obtained from the wild or from maturation. Wild P. vannamei broodstock will produce an average 150,000 nauplii per spawn. The broodstock are typically fished from the ocean and transferred to spawning stations. Spawning stations are usually temporary installations of tanks and portable aeration equipment that are established on the beach in areas where spawners are landed by local fisherman. Spawning station operators bid for broodstock; the price varies from US$15.00 to $80.00 per piece depending on supply and demand. Broodstock are discarded after spawning. When wild broodstock are not abundant, some spawning station operators purchase non-mated gravid females and ripe males and practice artificial insemination. Shrimp farmers believe that spawners produced from artificial insemination generally produce lower quality nauplii than spawners that are naturally mated. Spawners produced in captive maturation systems average 80,000 nauplii per spawn. Typically, broodstock are maintained for four months in a captive maturation system. Average production per captive maturation is approximately 400,000 nauplii during the 4-month period. Ecuador has made a major commitment to captive maturation in terms of investment in facilities. Enough captive maturation capacity already has been constructed to supply the country's entire nauplii requirements, if these facilities produce at levels achieved at Amorient Aquafarm in Hawaii. A total of 90,000 broodstock would be required to produce 18 billion nauplii from captive maturation. This number includes both males and females and assumes that maturation tanks are stocked at a 50/50 ratio. Captive maturation provides for the closing of the shrimp life cycle in captivity and the ability to maintain successive generations of shrimp isolated from wild stocks. The major advantage in captive maturation is control over the production system. Once the technology for captive maturation became readily available, a major investment was made in constructing maturation facilities in Ecuador (Table 4). The current maturation capacity is sufficient to provide the entire country with postlarvae solely from captive maturation. Unfortunately, many of these facilities no longer operate due to the impact of the IHHN virus.

Government Regulations

Considering the level of contamination of both BP and IHHN viruses in the Ecuadorian environment, finding a site suitable for the production of SPF stocks within the country is unlikely. Therefore, SPF stocks must be produced outside the country and shipped in, either as broodstock, nauplii or postlarvae. Current laws prohibit the importation of live shrimp into Ecuador. Thus, special permission must be obtained from the Ecuadorian government for the importation of SPF stocks to Ecuador. It should be noted that the Ecuadorian government allows importation of swine and poultry for breeding and stock improvement. 

Philippines

The Philippines islands (Map 2) are well suited for the development of shrimp aquaculture. The country comprises 7,000 islands with a coastline of approximately 17,000 km. It has a relatively narrow continental shelf, which is surrounded by clear, clean, deep ocean water. The Philippines has a tradition of aquaculture that originated long before the recent interest in modern shrimp culture. The country has more than 200,000 hectares of traditional, coastal, brackish-water fish ponds, most of which are used for the production of milkfish (Chanos chanos), and shrimp (P. monodon and P. indicus). The coastal climate in most of the Philippines is ideal for the culture of tropical marine shrimp. In addition, spawners of black tiger shrimp (P. monodon) the most commonly cultured shrimp in Asia are abundant in Philippine waters. The Philippines is also recognized as a leader in the development of shrimp hatchery and grow-out technology. The total production of shrimp in the Philippines has increased annually from the mid 1970s, when modern methods of shrimp culture were first introduced from Taiwan. In 1989, when the export price for the black tiger shrimp began to weaken, production began to decline. However, reports conflict as to whether production began to decline in 1990 or continued to increase as presented in Table 5. However, it is widely believed that the 1989 decline in pond bank prices discouraged some producers from stocking their ponds and caused others to radically change their production strategies, resulting in decreased production after 1989.

Aquaculture Practices

The traditional system of brackish-water pond aquaculture in the Philippines, involving polyculture of milkfish and shrimp, has been practiced for decades. Currently more than 200,000 hectares of ponds are devoted to traditional polyculture practices. More than 50,000 hectares of ponds are located on the Island of Luzon in or around Manila Bay within a few hours of the markets in Manila. In the mid-1980s, aquaculture rapidly shifted to the intensive system of pond culture a move that was influenced by technicians, advisors and investors from Taiwan. Taiwanese feeds and feed formulations became readily available, and ponds similar in design to those in Taiwan were built. In response to the increased demand for postlarvae, hatchery construction boomed. Black tiger shrimp production increased from 28,000 MT in 1985 to more than 40,000 MT in 1988. An estimated 4,000 hectares of intensive ponds were developed in the Philippines by 1989. Much of the new development of intensive shrimp farms has taken place on former sugarcane land on the Island of Negros in the region known as western Visayas. This development peaked in 1989, when the price for black tiger shrimp began to drop. Since 1989, little shrimp farm development has occurred in the western Visayas.

Traditional Polyculture

Traditional brackish-water ponds are built by hand on tidal mud flats. Water is exchanged twice per month during the high tides of the new moon and full moon. Pumping is generally not required. The ponds are shallow approximately 50 cm deep. Shrimp production is incidental to the production of fish; many farmers do not intentionally stock shrimp. The fry are introduced naturally during tidal water exchange. A combination of black tiger and white shrimp is produced. Annual shrimp yields average 20 to 60 kg per hectare. Extensive Shrimp Monoculture With the advent of shrimp hatchery technology in the mid-1980s, shrimp fry became abundant and relatively cheap. At the same time, pond bank prices for market-size P. monodon were very attractive (approximately $10 to 12 per kg for 30- to 40-gram shrimp). During this period, 30,000 to 50,000 hectares of traditional shrimp ponds were converted to extensive monoculture of black tiger shrimp. These ponds were typically stocked with 10,000 to 20,000 P. monodon postlarvae per hectare and achieved yields of 200 to 500 kg per hectare. In 1987 and 1988, these crops were worth from US$2,000 to $5,000 per hectare to farmers. However, when the pond bank price of shrimp dropped to less than $5 per kilo in 1989, the crop value decreased by half. Many of these farmers converted to milkfish. Milkfish production involves fewer start-up costs and less risk than shrimp production.

Intensive Shrimp Culture

During the period from 1985 to 1988 while some traditional farmers were converting to extensive monoculture, a new wave of shrimp culture development occurred that was patterned after the Taiwanese system of intensive shrimp culture. The investors in this new wave of modern shrimp farming were much different than those involved in traditional shrimp culture. They owned large tracts of land. Many were wealthy sugar planters, and nearly all had access to capital for investment. Initially, stocking rates followed the same pattern established in Taiwan. Stocking rates of 25 to 40 shrimp per square meter were common. Daily water exchange rates of 10 to 40 percent of the pond volume was required, and shrimp were fed up to 5 times a day. This system was very productive and profitable prior to the price reductions of 1989, achieving crop yields of 5 to 10 MT per hectare each. However, when the price of shrimp decreased to less than $5 per kg, these systems were no longer profitable. As the profit margin decreased, awareness of the importance of fry quality to production increased. Since 1989, profitability has been highly dependent on the ability of the shrimp fry to survive, grow, and utilize expensive feeds. In an attempt to adapt to the problem of low pond bank shrimp prices and high cost imported feed, the Philippine prawn growers have developed a strategy that is highly dependent on fry quality. The strategy involves stocking the ponds with low densities of shrimp 5 to 7 per square meter and growing the shrimp to larger sizes 40 to 60 grams than is common in other Asian countries. The higher price for 40- to 60-gram shrimp enables the Philippine growers to remain profitable. The system depends heavily on the ability of the shrimp fry to survive well, maintain high growth rates and attain a large market size. Therefore, a system of fry evaluation or stress testing was developed. Premium prices are paid for fry that are perceived to have the desired high performance characteristics. The highest quality fry routinely achieve survival rates of 90 percent and grow to sizes greater than 50 grams. However, only a few farmers were able to routinely maintain these standards. The data shown in Table 5 indicate that total production for black tiger shrimp has increased steadily since 1981. However, some loss in production occurred due to a sudden price decrease in 1989 and a natural disaster the eruption of Mount Pinatubo in 1991. Bob Rosenberry of Aquaculture Digest reports that 1991 aquaculture shrimp production was 30,000 MT, 27,000 MT of which were black tiger shrimp. Although the Philippine government's official figures are higher, the growers who were interviewed support Rosenberry's data. The data in Table 6 show that pond production of milkfish far exceeds the production of shrimp. The market for milkfish is domestic, and the price for this product remained firm throughout the 1980's. One of the reasons the Philippines has lagged behind Thailand and Indonesia in the production of black tiger shrimp for export is that the majority of traditional brackish-water pond operators have been reluctant to change their practices from polyculture of milkfish to monoculture of shrimp. Another reason is that the Philippine government levies a 30 percent duty on imported feeds and feed ingredients. Feed costs in the Philippines are the highest in the region. In Thailand and Indonesia, feed costs approximately $l per kilogram, but it costs approximately $l.30 per kg in the Philippines. When the price of black tiger shrimp suddenly dropped in 1989, shrimp farmers in the Philippines were at a competitive disadvantage. In addition, labor costs in the Philippines are higher than in Thailand or Indonesia. Finally, the Philippines' problems with political instability have made attracting foreign investment difficult.

Hatcheries

In 1988, approximately 380 shrimp hatcheries were operating in the Philippines. Since 1989, the number of hatcheries has declined to approximately 102 (Table 7), probably fewer than 60 of which operate routinely. Many hatcheries are small and produce less than 2 million postlarvae per month, but a few larger companies are capable of producing 5 to 10 million postlarvae per month.

Postlarvae

Philippine shrimp farms require a total of approximately 1.4 billion postlarvae. Wild postlarvae contribute little to that number. Most wild postlarvae are used in traditional or extensive systems because wild postlarvae are different sizes and ages, and intensive shrimp farmers prefer postlarvae of uniform size and uniform age. Postlarvae are normally sold after reaching the PL20 stage, or 20 days after they have metamorphosed to postlarvae. The price for postlarvae varies from $5.60 per 1,000 to $10 per 1,000. Traditional and extensive growers prefer the lower-cost postlarvae. Intensive growers will generally only buy the higher-priced, higher-quality postlarvae. The total value of postlarvae sold annually in the Philippines is equivalent to approximately US$10 to $12 million.

Nauplii

Hatchery survival from nauplii to PL20 averages 50 percent; therefore 2.8 billion nauplii are required for the Philippine shrimp industry. Virtually all nauplii come from wild broodstock. No spawning station operators provide wild nauplii to hatcheries, and no operations in the Philippines currently practice captive maturation. Spawners are collected by fishermen and sold to hatchery operators. Broodstock cost approximately $40 to $50 each, and only 50 to 75 percent of them will actually spawn. Each spawner purchased produces an average of 500,000 viable nauplii. This brings the cost of nauplii to approximately $0.10 per 1,000. The total value of nauplii used by hatcheries in the Philippines annually is approximately $900,000.

Spawners

The spawner requirement in the Philippines is approximately 9,000 per year. In the mid-1980s, Mas Bate Island was considered to be the most desirable area for collecting broodstock because they produced nauplii and postlarvae that performed better than those produced by spawners from other areas. In the Philippines, the belief is widely held that broodstock captured near shrimp farms and hatcheries do not perform as well as those captured in areas isolated from shrimp farming activities.

Standards Of PL Quality

The strategy of producing large shrimp by stocking low densities while maintaining relatively intensive production levels of 4 to 5 tons per hectare per crop depends greatly on the quality of the postlarvae. At low stocking densities of 5 to 7 per square meter, production depends on achieving high survival rates and on the shrimps' ability to maintain rapid growth rates until the desired market size is achieved. In the Philippines, fry quality has become such an important issue that several independent labs have been established to examine samples of fry from hatcheries before farmers commit to purchasing them. Some large farmers have established their own labs and maintain full-time technicians to monitor fry quality and other parameters that are important to production. This issue is particularly important for intensive farms. Muscle-To-Gut Ratio (MGR) Wild fry have generally been considered the standard in terms of fry quality. Microscopic observations of wild fry have revealed that their tail muscle diameter exceeds the diameter of the hindgut by a ratio of 4 to 1. Achieving muscle-to-gut ratios in excess of 4 to 1 is possible in the best quality hatchery-reared fry, but many hatcheries have difficulty maintaining this standard. Therefore, in the Philippines the belief is widely held that the quality of hatchery-reared fry can be predicted by how closely the muscle-to-gut ratio approximates that of wild fry. Monodon Baculovirus (MBV) The presence of P. mondon-type baculovirus (MBV) has become a major issue in the Philippines although no conclusive evidence exists that MBV adversely affects production.Monodon baculovirus occlusion bodies (OBs) have been observed in the hepatopancreas of shrimp postlarvae in the Philippines for many years. MBV is ubiquitous in the Philippines, and the OBs appear to be observable only when the shrimp are under stress. Therefore, the presence or absence of OBs in shrimp fry has become an indication of the postlarvae's quality. Postlarvae without the presence of OBs can be said to have been grown under relatively stress-free conditions. Furthermore, the lack of OBs in hatchery-reared fry is considered to be a reflection of the hatchery's standards of hygiene,  water quality and feed management. In the Philippines, the belief iswidely held that larvae which show no OBs perform better in ponds. Since very few hatcheries are capable of producing black tiger postlarvae with no OBs, postlarvae are rated by the percentage of MBV occlusion bodies present in a sample taken at harvest. The higher the rating, the higher the price will be for the postlarvae. Most shrimp farmers will purchase shrimp fry with MBV if the level of infection is considered low. A few farmers will not buy fry that have MBV. At least one hatchery group, Jamandre Hatcheries Inc., is able to consistently produce fry without the presence of occlusion bodies. However, in order to maintain this reputation, the company occasionally dumps fry considered below standard.

Stress Testing

In addition to microscopic examination for MBV, MGR and the presence of obligate pathogens, most Philippine shrimp farms will evaluate fry by submitting them to various tests. The simplest test is accomplished by tapping the side of the fry container. The best quality fry will respond by jumping and becoming very active; poor quality fry will have little reaction. A more rigorous test stresses the fry with a sudden change in salinity. A common standard is to drop the fry, which were cultured in a salinity of 32 ppt, into a container with brackish water of 15 ppt salinity. The fry are left for two hours, after which the survivors are counted. The best quality fry will have a survival rate of at least 98 percent.

Bent Body Syndrome

Bent body syndrome (BBS) is a relatively new phenomenon that is manifested by a deformity, usually of the third tail segment. Shrimp have been observed to display this deformity as early as the PL stage in hatcheries. Market-size shrimp that display this deformity are not saleable and represent a total loss to the producer. Recently on Negros, intensive ponds have been harvested with as much as 20 percent of the crop exhibiting bent body syndrome. No one has been able to determine the cause of BBS; further work must be done. Several years have elapsed since IHHN virus was first observed in P. monodon in the Philippines, but the virus has never been linked with any particular symptoms in the shrimp. Because of recent increases in the incidence of MBV and BBS in postlarvae produced from Mas Bate spawners, hatchery operators have tried to find new areas from which to collect spawners. Interestingly, when broodstock are collected in areas farther from the growing areas than Mas Bate, fewer incidences of MBV and BBS are observed. Tacloban on the Island of Leyte is currently the preferred source of spawners.

Government Regulations

Due to the level of MBV and IHHN virus contamination in the Philippine environment, production of SPF stocks under current standards of  shrimp farm operations is unlikely. Therefore, unless a major capital investment is made in facilities, SPF P. monodon stocks will likely be produced outside the country and shipped into the Philippines as either broodstock, nauplii or postlarvae. Current Philippine laws prohibit the importation of P. monodon broodstock, nauplii and postlarvae. Special permission must be obtained from the Philippine government for the importation of SPF stocks.

Thailand

Thailand (Map 3) has a 2,600-km coastline on the Gulf of Thailand and the Andaman Sea. Thailand's year-round warm weather makes it highly suitable for culturing marine shrimp. Trash fish landed as a by-product of the shrimp fishing industry provide a domestic source of ingredients for Thailand's shrimp feed industry. In addition, the country's highly developed agriculture sector also contributes large quantities of by-products that are used as shrimp feed ingredients. P. monodon spawners are readily available in Thailand. Further, the country has numerous skilled hatchery operators who were originally employed in the production of Macrobrachium rosenbergii fry. They had the benefit of years of experience because the M. rosenbergii industry began in the late 1970s. These technicians easily made the transition to marine shrimp production when the demand for P. monodon fry began to drive up prices in 1986. In 1991, Thailand produced 120,000 MT of shrimp, 90 percent of which was P. monodon. Thailand's long tradition of capturing and marketing seafood has provided a well-developed infrastructure for processing and exporting cultured shrimp. Thailand also has made major efforts in value-added processing. While total production is the second highest in southeast Asia after Indonesia, many disease and pollution problems have plagued the industry within the last two years. The answer to date has been to totally abandon unproductive areas and move to growing areas with better water quality. Whether this permanently solves the problem remains to be seen.

Aquaculture Practices

Polyculture of shrimp and fish in brackish water has been practiced for decades in Thailand. Prior to 1986, the predominant shrimp crop was the white shrimp, Penaeus merguiensis. The first area to develop large numbers of brackish water shrimp farms was the Chao Phraya delta just south of Bangkok. The culture method involved pumping large quantities of unscreened seawater into shallow earthen ponds. White shrimp fry were introduced with the water. Little feeding was required, and a modest yield of 300 to 400 kg per hectare per year was produced. Brackish-water shrimp culture grew from 10,000 MT in 1982 to 18,000 MT in 1986. The shrimp farming area also increased from 31,000 hectares to 45,000 hectares by 1986 (Table 8). In 1986, Thai shrimp farmers became interested in black tiger shrimp because it can be grown to larger sizes at much higher densities and with higher survival rates than other shrimp. Many farmers began to convert their extensive ponds to intensive culture of black tiger shrimp. In addition, new areas, primarily former salt pens, began to be converted to shrimp farms. The shrimp production area in Thailand increased from 45,000 hectares in 1986 to 71,000 hectares in 1989. In 1989, total production reached 93,000 MT, and the number of shrimp farms increased to more than 12,000. Two events caused major problems for the Thai shrimp farming industry. The first was a sudden drop in the world market price, which caused pond bank prices to farmers to fall from approximately $10 per kg to under $5 per kg. The second was the outbreak of disease due to poor water quality in the Chao Praya delta just south of Bangkok. As can be seen from Table 8, production fell by more than 16,000 hectares from 1989 to 1990. These ponds were all in the Chao Praya delta and still lie fallow. All new development after 1986 was targeted at the intensive production of P. monodon. The Chao Praya delta was the first area to be developed for intensive culture because the region had a strong tradition of shrimp culture and available land. It is a relatively confined body of water comprising numerous narrow, shallow canals or klongs, which carry a sufficient water capacity to provide for extensive shrimp farming or for salt production. However, the klongs became polluted when the highly eutrophic effluent of numerous intensive shrimp farms was discharged into them. In essence, the wastes of one shrimp farm were discharged at the intake of another. Within two years of the development of intensive shrimp farms in the Chao Praya delta, major areas were no longer able to produce shrimp at profitable levels. During the same time some farmers were abandoning their farms, the industry as a whole continued to expand and increase total production. This was because intensive shrimp farm activity moved south to areas with better water quality. Ironically, Thailand, the Southeast Asian country that most emulated theTaiwanese system in developing intensive shrimp culture,  also experienced a major collapse similar to that in Taiwan.

Hatcheries

Currently 488 hatcheries operate in Thailand, according to government sources (Table 9). Many are small-scale hatcheries that produce fewer than 10 million postlarvae per year. A few large hatcheries are capable of producing 70 to 100 million postlarvae per year. Thailand's total annual demand for postlarvae is approximately 6 billion, with a value of US$36 million, nearly all of which are produced from hatcheries. Presently Thailand has no shortage of P. monodon fry, and the hatchery sector is quite competitive. Consequently, the price for postlarvae is among the lowest in southeast Asia, averaging less than $6 per 1,000. Many of the materials for postlarvae production cost very little.

Postlarvae

Postlarvae in Thailand are produced in virtually any type of vessel that will hold seawater. Backyard hatchery operations, which need not be located near the sea, are numerous. Such hatcheries usually consist of a 20- to 100-MT seawater storage tank and many small larval rearing tanks. Larval-rearing tanks average from 1 MT to 10 MT in volume. Backyard hatchery operators generally produce only postlarvae. They purchase all of the necessary factors, including seawater, nauplii, algae and feeds. Trucks bring seawater to fill the hatchery storage tank on a regular basis for a fee. Algae can be purchased from an algae culture specialist. The shrimp are fed almost any available by-product, including bits of fish and squid that are washed through a fine screen. Egg custard and formulated diets such as Frippak are also used. Artemia is used minimally because it is considered expensive. Hatchery survival is highly variable, ranging from 0 to 90 percent. The larger scale hatcheries in Thailand are patterned after the Taiwanese hatchery system, using 40-MT concrete tanks with limited water exchange and aeration. These facilities, like the small-scale hatcheries, place a premium on low-cost fry production and little emphasis on fry quality. Survival rates in the large-scale hatcheries are also highly variable. The total demand for postlarvae in Thailand is approximately 6 billion.

Postlarvae Quality

Thai farmers place little premium on postlarvae quality and will accept postlarvae that are relatively active. It is safe to say that most of the postlarvae produced in hatcheries in Thailand are of similar quality. Unlike the Philippines, Thailand has never had enough wild postlarvae available for shrimp farmers to make a comparison. The only concession observed regarding fry quality is that some of the more progressive Thai shrimp farmers operate nursery tanks and stock postlarvae at PL40 to PL50 in order to ensure higher survival rates in their ponds.

Nauplii

Once broodstock are transferred to the spawning facilities, they are eyestalk-ablated and placed in 40-ton concrete maturation tanks. While in the tanks, they are fed a minimum diet of mussels, crab and trash fish and are allowed to mature, mate and spawn. When nauplii are observed, the entire tank is drained to collect them. The nauplii are then either sold or placed directly in larval rearing tanks. Each female shrimp will produce an average of 2 million nauplii within a 4- to 6-week period. The broodstock are then routinely discarded. The maturation diet is given little emphasis because farmers believe that broodstock are discarded before dietary deficiencies will affect nauplii production. The major emphasis is on producing low-cost nauplii. Nauplii are sold for $0.06 per 1,000, and the production cost in this system is said to be less than $0.03 per 1,000. Thailand uses a total of 18 billion nauplii, which are valued at US$1.08 million.

Broodstock

Broodstock in Thailand are obtained from the Andaman Sea just south of Thailand's border with Myanmar (formerly Burma). Spawners are caught by Thai fishermen and sold to hatchery operators. Some operators buy broodstock and run modified maturation facilities, thereby providing a market for both male and female broodstock. Females sell for approximately $50 each and need not necessarily be gravid. Males sell for $4 each. The broodstock obtained from the Andaman Sea are among the largest in southeast Asia. Many females weigh in excess of 200 grams. It is not unusual for one of these broodstock to produce in excess of 2 million eggs in a single spawn. Government Regulations The government currently controls the importation of shrimp species in Thailand. Government permission would have to be obtained to introduce SPF stocks to the country. Importers should apply to import SPF stocks directly to the Director of Fisheries in Bangkok.

Indonesia

Indonesia (Map 4) comprises more than 11,000 islands that span more than 3,000 miles from Sumatra in the west to Irian Jaya in the east. The country has excellent resources for brackish-water shrimp farming. The climate is tropical with relatively even temperatures and rainfall throughout the year. P. monodon spawners are relatively abundant throughout the year, and a tradition of brackish-water aquaculture has been practiced for centuries.

Aquaculture Practices

Traditional Shrimp Culture

Most of the traditional ponds, known locally as Tambaks, are concentrated on the north coast of Java, south Sulawesi and north Sumatra. More than 250,000 hectares of these ponds currently operate. Most traditional ponds typically produce both fish and shrimp. Milkfish fry, collected in shallow coastal areas, are stocked in the ponds, where they are grown to market size. Shrimp fry are introduced naturally when water is brought into the ponds, or they are captured along with the milkfish fry. These ponds are usually very shallow approximately 50 cm deep and water is exchanged by tidal action during the new moon and full moon each month. As the demand for black tiger shrimp in Japan increased in the early 1980s, prices also rose rapidly. Brackish water pond operators attempted to collect and stock increasing numbers of wild fry to increase yields of this valuable species. At one point, the price of black tiger fry reached $40 per 1,000. In order to meet the growing demand, hatchery technology from Taiwan, France and the United States was introduced.

Shrimp Monoculture

The introduction of shrimp hatchery technology combined with imported Taiwanese growout feeds resulted in rapid growth of both semi-intensive and intensive shrimp farms. This activity originally was concentrated in east Java, then spread throughout Java to Bali, Sumatra, and south Sulawesi. Government sources estimated total shrimp production from aquaculture at 105,000 MT in 1991.

Hatcheries

Currently, more than 200 large-scale hatcheries, which have a total annual production capacity of 50 to 150 million postlarvae, operate in Indonesia. Probably as many backyard hatcheries operate, producing 2 to 5 million PLs per year. Hatchery construction boomed in response to shrimp fry prices averaging $15 to $20 per 1,000 in 1986. Table 10 shows the increase in the number of hatcheries from 1984 to 1989. A number of influences affected the development of hatchery technology in Indonesia. The first of the large-scale hatcheries was built as the result of the export of Taiwanese shrimp hatchery technology to Indonesia. The main feature of these hatcheries was square, common-walled cement tanks enclosed in a building that was kept dark most of the time. Water intake systems were simple pipes into the sea; the pipes drew unaerated, raw seawater into the hatchery. The Taiwanese system required very little seawater for exchange. Also, little attention was given to culturing marine algae to feed postlarvae stages. Skeletonema sp. was the preferred species, and Tetraselmes sp. was frequently used in addition. Often Tetraselmas was the only algae used because it was easier to culture. Animal quality received little attention. Within a few years, Western-style hatchery technology was introduced from France and the United States. These hatcheries emphasized the separation of functions. Algae is cultured in separate rooms from other hatchery activities. Chaetoceros species are preferred. More emphasis is placed on maintaining water quality by water exchange in the larval rearing tanks. Also, Western-style hatcheries typically employ more sophisticated designs for seawater intakes, seawater storage and treatment. The third type of hatchery is the backyard hatchery, which was first established in 1988. Patterned after similar hatcheries in Thailand, they are established in east and central Java in close proximity to major growing areas. Algae and nauplii are usually purchased from large-scale hatcheries. Backyard hatcheries are generally operated by independent owner-operators who can produce postlarvae at very low costs. However, each hatchery run usually produces small quantities less than 500,000 postlarvae and production is inconsistent. Pond operators who stock low densities and practice traditional polyculture with milkfish are the most frequent customers of backyard hatcheries. Postlarvae prices depend somewhat on which system of hatchery production is employed. The highest price $6 to $8 per 1,000 is paid for postlarvae from hatcheries practicing western-style hatchery management. The lowest price approximately $4 to $6 per 1,000 goes to backyard hatcheries. A price differential dependent on the style of hatchery management indicates that shrimp farms perceived a difference in quality.

Postlarvae

Approximately 90 percent of the postlarvae sold in Indonesia are produced in hatcheries. Although postlarvae are still collected in the wild, they are generally sold to growers who have traditional and extensive culture operations. Postlarvae from hatcheries are sold at the PL20 stage. The total number of postlarvae needed by Indonesian prawn growers is estimated to be 6 billion per year. If Indonesian hatcheries all were to produce postlarvae according to their rated capacity, nearly twice that amount could result. This is why the price for postlarvae has been decreasing in recent years. However, for periods in 1991, shrimp postlarvae were in short supply. Disease in the hatchery stage was blamed for the shortfall. In 1991, the price for postlarvae fluctuated from a minimum of $4.50 per 1,000 to a maximum of $10 per 1,000. Prices currently average from $5 to $7 per 1,000.

Nauplii

No known operations specialize in nauplii production in Indonesia. The major market for nauplii is backyard hatcheries, which purchase excess nauplii from large hatcheries. The price for nauplii is approximately $0.10 per 1,000. The Indonesian shrimp hatchery industry needs an estimated total of approximately 18 billion nauplii.

Broodstock

Indonesia has a major resource for black tiger shrimp within its coastal waters. Spawners and broodstock can be obtained within a few miles of many of the 200 large-scale hatcheries throughout the country. By far the major concentration of hatcheries is on Java. Yet the Indonesians prefer to obtain broodstock in north Sumatra at Banda Aceh, more than 1,000 miles away. These spawners must then be flown to east and central Java, Bali and as far away as south Sulawesi. The only explanation given for obtaining spawners in Banda Aceh is that they are larger and perform better than those collected from other areas. The reasons for their improved performance are not known. Spawners from Banda Aceh cost approximately $50 each. Spawners from other areas such as Lombok may cost $20 to $30. Broodstock need not be gravid when captured because most hatcheries employ a modified captive maturation system. The broodstock are ablated and, within 5 days, will mate and spawn. They are held until they have spawned a maximum of four times, and then they are discarded. During the time the broodstock are held for mating and spawning, they are fed with mangrove crab or squid. Indonesian shrimp hatchery operators believe that each successive spawn is less valuable in terms of the nauplii's overall performance in the hatchery. They will use each female's first two spawns to stock their own hatchery and sell the nauplii from the third and fourth spawns to backyard hatchery operators. The total number of spawners required for the Indonesian shrimp hatchery industry is estimated to be approximately 9,000 per year, assuming the average spawner will produce 2 million nauplii.

Government Regulations

Any importation of live shrimp as broodstock or postlarvae for growout requires permission from the Directorate of Fisheries. Importation is generally allowed when the final product is an exportable commodity. The most recent live shrimp importation case involved a Taiwanese sponsored joint venture on a P. japonicus farm. Postlarvae and feed are imported from Taiwan to Bali, and live Kuruma prawns are then exported to Japan. The feed and postlarvae for this project are imported duty free.

IV.Summary of AquaculturePractices and Problems

Shrimp Aquaculture Trends That Support the Value of SPF Stocks

Aquaculture practices in each of the study countries have developed along the lines of maximizing each country's resources. All of the study countries at one time have had an abundant source of wild postlarvae. In Ecuador, the Philippines, and Indonesia the early traditional or extensive system of shrimp culture was based on exploiting the wild postlarvae resource. Improvements to production initially resulted from improved pond design, water quality management and the introduction of formulated feeds. Hatchery technology was introduced as the demand for postlarvae increased and wild postlarvae resources were no longer sufficient to meet the demand. In Thailand, hatchery technology became the focal point for production improvement because Thailand's traditional shrimp farms depended on wild P. merguiensis postlarvae. Thailand never had the benefit of a natural source of P. monodon postlarvae. Once P. monodon postlarvae became available in Thailand, shrimp farmers quickly switchedto this species. Initially, hatchery-reared postlarvae were considered to be of inferior quality to wild postlarvae and were not readily accepted by shrimp farmers. Once hatchery technology advanced to the point where hatchery-reared postlarvae were readily accepted by shrimp farmers, the number of hatcheries grew rapidly in each of the study countries. The growth in the number of hatcheries placed a great deal of pressure on the spawner resources. The way each country has dealt with the problems of spawner supply and spawner quality is a leading indicator of the potential value of SPF stocks.

Ecuador

In Ecuador, spawner availability is seasonal. During December through March, spawners are available in the southern part of the country. From June through November, they are available in the north. In response to the year-round demand for spawners and nauplii, numerous spawning stations have been established. Spawning stationsprovide the majority of the nauplii used by  the country's hatcheries. The biggest problem with the system of spawning stations is its dependence on the availability of wild broodstock from the sea. The supply is highly variable, and at times, spawners cannot be captured. Another problem with the  system of independent spawning stations is that they have been implicated in the spread of disease. In 1990, a serious outbreak of vibriosis occurred that caused a temporary closure of nearly all the hatcheries in Ecuador. Some marginal hatchery operations never reopened. Spawning stations were suspected to be one of the major contributing factors in the spread of the disease. In an effort to avoid the problems associated with the collection of wild broodstock, a major investment has been made in captive maturation facilities in Ecuador. The current captive maturation capability is sufficient to supply all nauplii required by the entire industry. Ecuador presently has 25 maturation facilities that have a combined ability to use 153,450 broodstock annually. The existing maturation capability in Ecuador, although largely unused, represents a ready market for SPF broodstock. Recent trials with SPF postlarvae in Ecuador generated a renewed interest in the operation of maturation facilities using SPF broodstock. Philippines In the Philippines, postlarvae quality is perceived to be related to spawner quality. Most hatchery operators believe that spawner quality depends highly on where the spawners are collected. Most Philippine shrimp farmers consider the MBV virus to be a major indicator of postlarvae quality. Postlarvae in the Philippines are rated by the level of MBV occlusion bodies observed in the hepatopancreas at the time of purchase. Postlarvae with fewer occlusion bodies generally bring a higher price. No relationship has been documented between the level of MBV occlusion bodies in spawners and the occurrence of occlusion bodies in postlarvae. However, the belief is widely held that the incidence of MBV will be less frequent if spawners are collected in places isolated from shrimp growing areas. The practice of moving offshore from shrimp farming areas to obtain spawners began in the mid-1980s. At that time Mas Bate island was thought to be the ideal location for collecting good quality broodstock. Mas Bate island is located north of Panay and Negros islands (Map 2, p. 16), among major shrimp growing areas. It is centrally located within the Philippine archipelago and easily accessed by broodstock collectors. As shrimp culture began to intensify in the late 1980s, the level of MBVcontamination in Philippine shrimp stocks began to noticeably increase. Hatchery operators no longer obtained the same performance from Mas Bate spawners. In the search for better quality broodstock, hatchery operators began to look for sources that were even farther away from growing areas. The present preferred source of spawners is Tacloban on the island of Leyte. Tacloban is on the eastern edge of the Philippine archipelago adjacent to the deep, clear, clean waters of the Pacific Ocean. The best quality spawners in the Philippines now appear to be found only in the least contaminated environments, which are the farthest from the areas of shrimp culture.

Thailand

In Thailand, the relationship between the the presence of MBV in postlarvae and the animals' performance has never been documented. Shrimp farmers do not place a premium on postlarvae with fewer MBV occlusion bodies. The price of postlarvae is related more to their size and age at the time of sale than to other factors. Very few hatchery operators in Thailand also run shrimp farms; competition among the many hatcheries that produce postlarvae is keen. Therefore, hatchery operators have great incentive to produce low-cost postlarvae. Although Thai hatchery operators will make every effort to reduce hatchery operating costs, they choose to purchase broodstock from Phuket on the Andaman Sea, the highest priced source. Prices for Andaman Sea broodstock are in excess of $50 per piece. Spawners from the Andaman Sea are preferred because they perform better in the hatchery. They are large, have a high rate of fecundity, and their larvae grow well and have better survival rates than others.

Indonesia

Indonesian hatcheries operate much like those in Thailand, except that animal quality appears to get more recognition. Although prices for postlarvae are very competitive, western-style hatcheries that employ relatively high water exchange rates command a higher price for their postlarvae. P. monodon broodstock are more plentiful in Indonesia than in either Thailand or the Philippines. Broodstock can be easily captured off the coast of all major growing areas. However, these broodstock, are not in high demand and sell for approximately $20 each. Indonesian shrimp hatchery operators prefer to purchase broodstock from Banda Aceh at the northern tip of Sumatra. Banda Aceh broodstock cost $50 each, more than twice the cost of broodstock from other parts of Indonesia. In addition, they must be air-freighted more than 1,000 miles to the areas where most of the hatcheries are located. Indonesian hatchery operators purchase Banda Aceh broodstock for the same reasons that Thai hatchery operators purchase broodstock from Phuket: the broodstock are larger and produce more nauplii, which perform better in the hatchery. Banda Aceh and Phuket are both located on the Andaman Sea, and the broodstock preferred by the Thais and the Indonesians probably come from the same population of shrimp. Neither the Thais nor the Indonesians interviewed were aware that the other preferred broodstock from the Andaman Sea, nor were they able to provide a reason for preferring these broodstock other than that the animals' were larger and produced more nauplii, which produced better results in the hatchery. Neither the Thais nor the Indonesians seemed to realize that the Andaman Sea is isolated from the major growing areas of both countries nor that they were following a pattern of broodstock selection very similar to the pattern in the Philippines. Nevertheless, this pattern of hatchery operators in all three countries selecting broodstock that are obtained from areas that are the farthest removed from shrimp growing areas appears to be increasing.

Andaman Sea Broodstock

In the mid-1980s before the boom in shrimp culture development in Southeast Asia, SPF broodstock were easily obtained from Penang, Malaysia. SPF P. monodon were originally imported to Hawaii by Aquatic Farms from Penang. If a triangle were drawn from Penang to Phuket to Banda Aceh in the Andaman Sea (Map 5), the distances are such that speculation is reasonable that the broodstock resource for all three places is probably from the same population of shrimp. Although no historical data exist on the broodstock from Phuket or Banda Aceh, the shrimp from Penang were known, at least at one time, as likely to be free of MBV, IHHN and other obligate pathogens. Therefore, the broodstock from Phuket and Banda Aceh also could have been assumed to be free of these pathogens at that time. A recent study by Danny Fegan (Fegan et al, 1991) indicates that the spawners captured off Phuket have a relatively high level (5.7 percent) of contamination with the MBV virus. However, because spawners from the Andaman Sea remain the farthest removed from the sources of viral contamination and a historical preference has been established for them, they likely will continue to be preferred in those two countries until a better alternative is found. V.The Market for SPF Broodstock, Nauplii and Postlarvae All the study countries have active markets for broodstock, spawners, nauplii and postlarvae. Table 11 provides the quantities required, average prices and total values for each country.

Ecuador

In Ecuador, hatchery-produced postlarvae vary in price between US$3 and $8 per 1,000. The average price in 1991 was approximately $4 per 1,000. Postlarvae typically are produced from wild nauplii. Assuming that SPF broodstock were available, postlarvae from SPF nauplii likely would sell for a similar price. This would depend on whether SPF postlarvae perform as well as postlarvae produced from wild spawners. The total value for postlarvae in Ecuador in 1991 was $36 million. In 1991, the average price for nauplii in Ecuador was approximately $0.75 per 1,000. Assuming that SPF nauplii perform as well as those from the wild, SPF nauplii should sell for the same price. This represents a potential market valued at $13.5 million annually. Broodstock prices in Ecuador are typically very low, ranging from $2 to $4 per piece. This is because the IHHN virus causes nauplii and postlarvae produced from captive maturation to perform poorly in production ponds. However, Ecuador is unique among the study countries because a major commitment was made to construct maturation facilities prior to the identification of the IHHN virus. Therefore, the country has a ready market for broodstock that can produce nauplii able to perform as well as those from the wild. SPF broodstock in Ecuador are likely to be in high demand because they would enable hatchery producers to use their captive maturation capacity fully. Captive maturation depends on both males and females, so a pair of SPF broodstock probably would be worth at least as much as a wild spawner. Therefore, assuming that a pair of SPF broodstock will have a value of US$50 is reasonable. If all the currently available maturation capability in Ecuador were to be fully employed, approximately 150,000 broodstock would be required. The total market for SPF broodstock in Ecuador would be $3.75 million annually. Captive maturation has failed in Ecuador because of problems with the spread of the IHHN virus and the high incidence of runt deformity syndrome (RDS). Because SPF broodstock have been clearly shown to eliminate the problems associated with RDS, they should have a value similar to wild broodstock. 

Philippines 

In the Philippines, postlarvae sell for $7 to $10 per 1,000. Postlarvae that are free of MBV occlusion bodies are at a premium. Therefore, SPF postlarvae are likely to be well received initially there. If SPF postlarvae perform up to expectations, the premium price is likely to continue. However, SPF P. monodon have yet to be tested in production trials, and speculation is premature on their long-term acceptance. No spawning stations operate in the Philippines, and hatcheries do not typically sell nauplii to each other. Therefore, the price for nauplii was estimated based on the costs of a hatchery purchasing spawners and producing its own nauplii. Maturation systems are not normally used, and broodstock is usually spawned once and discarded. Attempts have been made to spawn broodstock more than once, but hatchery operators reported that nauplii quality diminished with each successive spawn. If nauplii were to be sold, they probably would sell for approximately $0.20 per 1,000, and the total value would be $900,000 annually. The best quality spawners sell for approximately $50 each in the Philippines. However, if SPF broodstock were able to produce postlarvae that performed as well or better than the best quality postlarvae, the SPF broodstock would likely sell for $50 per pair. The Philippines have no ready market for SPF broodstock because captive maturation is not practiced. In order for SPF broodstock to gain wide acceptance, the technology for captive maturation must be demonstrated to be superior to the current methods of producing nauplii.

Thailand

In Thailand, P. monodon postlarvae sell for approximately $5 to $7 per 1,000, among the lowest prices in southeast Asia. Thailand has a very competitive hatchery sector. Price is the first consideration, and quality ranks as a secondary consideration. Therefore, before SPF postlarvae can make a significant impact, they initially will have to be sold at a competitive price and clearly demonstrate superiority to the postlarvae currently being produced. Thailand requires an estimated 6 billion postlarvae with a value of approximately $36 million annually. Nauplii in Thailand are produced from wild spawners. Spawning stations sell nauplii, and hatcheries sell excess nauplii. Broodstock are ablated and allowed to spawn several times before they are discarded. Farmers perceive a difference between the quality of nauplii from the first spawn and those from the third or fourth spawn. Nauplii that are sold are usually of inferior quality and are sold mostly to operators of small scale or backyard hatcheries. The price for nauplii in Thailand is the lowest in southeast Asia at approximately $0.06 per 1,000. At this price, the total market for nauplii is a little more than $1 million per year. Broodstock sell for $50 per piece, approximately the same price as in the Philippines. Male shrimp cost approximately $4 per piece. Spawner-size females, whether gravid or not, will bring the same price. Annually, the Thai shrimp farming industry uses an estimated 9,000 spawners, which have a total value of $450,000.

Indonesia

In Indonesia, the prices for P. monodon postlarvae are similar to those in Thailand: $5 to $7 per 1,000. However, in early 1992, a shortage of postlarvae caused the price to increase to approximately $10 per 1,000. The shortage reportedly was due to widespread disease problems in the country's hatcheries. Because disease is a major problem in Indonesia, SPF postlarvae probably would be well accepted. Many of the country's farmers operate on a small scale, and most practice extensive culture methods. Therefore, SPF postlarvae would be unlikely to sell for much more than the $5 to $7 average price, except during periods when other sources of postlarvae are limited. In Indonesia, nauplii are produced from wild spawners in hatcheries. Indonesian farmers believe as do Philippine and Thai farmers that nauplii quality drops with each successive spawn. Theselling price is low, averaging $0.10 per 1,000, because only second-quality nauplii are sold there. Broodstock are obtained throughout the country, but those from the Andaman Sea are preferred. At times these broodstock are in short supply. SPF broodstock probably would be welcomed in Indonesia because the industry continues to expand, and broodstock availability has been cited as a constraint to expansion. Also, Indonesians are accustomed to shipping broodstock long distances. Therefore, buying broodstock from abroad would not be considered a serious constraint. Experience with captive maturation has been limited, and more work must be done to ensure that quality nauplii are produced from captive broodstock. If problems with quality can be resolved, SPF broodstock would probably sell for approximately $50 per pair.

Literature Cited

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