Current Status of Transboundary Fish Diseases in Myanmar: Occurrence, Surveillance, Research and Training
Saw New Year
Department of Fisheries
Sinn Min Road, Ahlone Township
Yangon, Myanmar
I. Current Status of Koi Herpesvirus Disease (KHVD) in the Production of Common Carp and Koi
I-1. Production of Common Carp and Koi
a. Production of Common Carp
To initiate first development of freshwater aquaculture, Myanmar imported some exotic species such as tilapia (Oreochromis mossambica), kissing gouramy (Trichogaster pectoralis) and common carp (Cyprinus carpio) in 1954. Common carp was imported from Indonesia and in 1965, the mirror carp (Cyprinus carpio) was imported from Israel. But up to 1970, culture of common carp was not popular among the fish farmers. The fish was new to the people of Myanmar with its colorful yellow color that they correlated as significant with the Buddhist religion. The Myanmar-Chinese people begun to eat common carp since the fish is rich in fat. Freshwater fish culture is now well established in Myanmar using various species of major carps such as catla (Catla catla), rohu (Labeo rohita) and mrigala (Cirrhina mrigala) that inhabit the surface layer, middle layer and bottom layer of water bodies, respectively. Up to 1995, freshwater fish, including cultured fish, was not allowed for export as it was solely for domestic consumption.
In some areas, common carp is cultured as a substitute fish for mrigala, but not in large quantities. Common carp inhabits the bottom layer of the pond and browse the pond dikes. This habit has been a major constraint for common carp culture because the fish farmers worry that the fish may cause dike erosion. In general, common carp culture comprises only 20% of the volume of other carps being cultured.
After 1995, freshwater fish produced in Myanmar was allowed for export
since production exceeded the domestic consumption (Table 1). Myanmar
usually exports major carps to Bangladesh where they command a higher
price. However, common carp remains for domestic consumption. The fish
is normally cultured in earthen ponds and rarely in tanks. In terms of pond
sizes, the smallest ponds are 0.1 ha, while the largest ponds are 10-20 ha.
Small ponds are located in the upper region of Myanmar and the larger ponds
are located in the lower region of the country, especially in river delta areas.
Small-scale fish farms normally purchase the fingerlings from government
or privately-owned hatcheries. Rice bran and ground-nut oil cake are common
feed for the freshwater fish. Recently, a new feed type like the floating pellet
was developed and became more popular among the fish farmers.
Table 1. Yearly freshwater fish production record in the last 5 years
Large-scale fish farm systems include nursery ponds, transition ponds,
and rearing ponds in the farm design. The fish fry of 3-5 day old hatchlings
are nursed in the nursery ponds. This procedure needs skill and experience
to produce about 25-30 % survival. When the fingerlings attain the size of 2-
3 inches after about 45 days rearing period, they are transferred to transition
ponds where they are grown up to 500 g in one year. They are called yearlings
and are used as stockfish in grow-out ponds.
Common carp was found to be the appropriate species to culture in rice
fields. The Department of Fisheries has stocked good quality fish seed
including common carp into the reservoirs, lakes, natural impoundments,
rivers, streams and natural water bodies to maintain the fishery resource.
Because of this, the common carp can be found in the wild habitats now.
Aside from this, Myanmar has a local strain of common carp found in
the Inle Lake of the Southern Shan State in the northern region of Myanmar.
However, the appearance, color, and small size of the fish, and the texture of
the flesh make it unattractive for culture. This fish is only consumed by poor
people in rural communities near the lake.
Spawners of common carp for seed production are selected from among
the largest fish in grow-out ponds. Common carp is easy to breed from February to May each year. Fish farmers can easily produce common carp
seed or they may purchase fingerlings from government and private hatcheries.
The first common carp fish stock was imported from Indonesia in 1954, but the fish has been domesticated ever since the first import. Common carp is not included in the fishes that are exported due to lack of demand. Due to repeated inbreeding of cultured common carp, it is assumed that the genetic characteristic has declined and this may lead to poor resistance or susceptibility to diseases in long term.
b. Production of Koi
Koi is also known as colored carp. It is a popular ornamental fish in
Myanmar and normally found in aquaria for hobbyists. It has never been
reported that koi is produced commercially in Myanmar. Seed production
method is similar to common carps, but the colorful koi may command much
higher price. There is no information on the fish's genetic management,
mutation, and other sophisticated technologies practiced in Myanmar. Some
attractive and beautifully colored koi may be imported illegally.
I-2. Koi Herpesvirus Disease (KHVD) of Common Carp and Koi
No information on any outbreak of koi herpesvirus disease (KHVD) has been reported yet. Importation of koi for ornamental purposes is very few and KHVD is not being analyzed since koi trade is not common. Culture of common carp is also small-scale and no report of KHVD outbreak is available.
I-3. Handout on KHVD
Despite the absence of KHVD outbreak in Myanmar, the Disease Section under the Department of Fisheries has published a handout on KHVD as a preventive measure. It is published in Myanmar language (Fig. 1). The handout contains the following information:
a. External and internal signs
b. Secondary diseases associated with KHVD
c. Primary cause
d. Affected age
e. Diagnostic tests
f. Transmission
g. Preventive and control measures
Fig. 1. The handout on KHVD which is distributed free of charge to farmers
II. Current Status of Viral Diseases in the Production of Shrimps and Prawn
II-1. Production of Shrimps
a. Production of Tiger Shrimp (Penaeus monodon)
In the 1970s, shrimp production originated from a purely traditional method commonly called "trap and hold", whereby shrimp production in very large ponds came mainly from postlarvae (PLs) that came in with the tide and derived nourishment from available natural food. In the past, even this method was not popular among the people of Myanmar. However, the number of traditional shrimp ponds increased year by year. The Department of Fisheries (DOF), under the Ministry for Livestock and Fisheries, implemented a 3-year project on shrimp aquaculture development that was started in 1999-2000 and ended in 2002-2003. This was followed by another 3-year project which the Ministry for Livestock and Fisheries started implementing in 2003-2004 to last until 2005-2006. The first project included the development of all culture systems such as extensive system, extensive plus system and semi-intensive systems. The second project encourages the development of intensive systems only. The yearly shrimp production recorded from various culture systems is shown in Table 2.
Table 2. Yearly production of cultured shrimp
Myanmar has rich resource of tiger shrimp spawners in the Andaman
Sea and Bay of Bengal. There are 29 existing shrimp hatcheries owned by
the government and the private sector capable of producing about 600 million
PLs/year. Existing shrimp hatcheries can supply the requirements of the growout
farms.
Before the hatcheries were successful, some PLs were imported from
Thailand in 1999-2000. Due to uncertified importation, disease outbreak of
white spot syndrome virus occurred which was later transmitted horizontally
to other farms. Black tiger shrimp spawners have not been imported, but
they are exported to some Asian countries like Vietnam, Thailand, Malaysia
and Taiwan.
b. Production of Pacific White Shrimp (Litopenaeus vannamei)
Generally, Myanmar does not allow the culture of Pacific white shrimp,
but some shrimp farmers requested the Ministry of Livestock and Fisheries,
and the DOF to allow importation of the species. After several consultations
made with NACA, SEAFDEC and other agencies, the DOF decided not to
allow importation and culture of L. vannamei to prevent the introduction
and outbreak of Taura syndrome virus (TSV). Therefore, Myanmar has no
problem with TSV outbreak at present.
c. Production of Freshwater Prawn (Macrobrachium rosenbergii)
It is indeed fortunate that Myanmar has very good sources of god quality
freshwater prawn (M. rosenbergii). However, the technology for freshwater
prawn culture in Myanmar is not well developed. Generally, the prawns are
cultured with freshwater finfishes like Chinese carp and other carps.
Monoculture of the prawn was attempted by private companies during the
last 2-3 years, but due to the uneconomically viable results, the system was
converted again to polyculture or mixed species culture.
II-2. White Spot Syndrome Virus (WSSV)
The first 3-year project of shrimp aquaculture that commenced in the year 1999-2000 triggered a sudden increase in intensive shrimp ponds that caused imbalance in the supply of shrimp PLs from the local shrimp hatcheries. In that year, some shrimp farmers were allowed to import shrimp Pls from Thailand. Due to high stocking density, ignorance of best pond management, and lack of PCR analysis, the shrimp ponds stocked with imported Pls experienced outbreaks of white spot disease that spread to other ponds through horizontal transmission. Shrimp farmers lost tremendously and the disease almost paralyzed the development of the shrimp industry in Myanmar. The disease has become a major threat to shrimp aquaculture development where the P. monodon is the only species for culture. Normally, WSSV was found in shrimp stocked after 20-60 days. According to the climatic condition, shrimp culture operations were initially done from December to April. The period between November and February is the winter season and the water temperature goes down to 23-240C. In that situation, the feeding rate of the shrimp decreases and most diseases occur in that period. The DOF established a laboratory for PCR analysis only in the year 2002. Before that, the local hatcheries sent broodstocks and also PLs to Thailand for PCR check up. Up to year 2000, the broodstocks harvested from the wild were found WSSV-free. However in 2003, some spawners were found positive for WSSV after PCR analysis. This indicates that the disease has already spread to wild stocks. WSSV usually causes 100% mortality in infected stocks. Currently, DOF has a Disease Section that is equipped with a laboratory capable of conducting PCR analysis. In 2002, trainings and monitoring of WSSV, TSV, IHHNV, MBV and Vibrio spp. were conducted in collaboration with the Food and Agriculture Organization (FAO) of the United Nations and Myanmar DOF.
II-3. Taura Syndrome Virus (TSV)
Myanmar has not allowed the importation and culture of Litopenaeus vannamei yet and there is no information on TSV occurrence.
II-4. Significant and Emerging Disease of Macrobrachium rosenbergii
Culture of freshwater prawn is by polyculture methods with Chinese carps
or major carps. As it is very extensive due to very low stocking density, there
has been no information on the occurrence of significant disease or disease
outbreak in this species.
III. Surveillance, Monitoring and Diagnosis of Diseases of Aquatic Animals
III-1. Responsible Facility and Personnel
Facility location: Department of Fisheries
a. Fish Disease Section
Shukhintha Road, Thaketa Township, Yangon, Myanmar
b. Contact personnel
Ms. Nwe Ni Aye
Section Head
Tel : 095-01-541294
Fax : 095-01-228258
E-mail : DOF@mptmail.net.mm
The DOF staff makes occasional visit to fish and shrimp farms, which
they monitor and survey. Sometimes, the Fish Disease Section contacts the
Township Fisheries Officers, or the farmers, themselves, contact the staff of
the Fish Disease Section.
III-2. Diagnostic Capabilities and Major Diseases Aquatic Animals
a. Laboratories
1. Government
DOF, Fish Disease Section-Level I and Level III (PCR)
Tel: 01-541294, Fax: 01-228258
E-mail : DOF@mptmail.net.mm
2. Private-based-Level III PCR
3. University-based-Levels I and II
b. Economically-Important Diseases
Name of disease: WSSV, IHHNV
Affected animals: P. monodon
Level of diagnosis: Level III (PCR)
IV. Quarantine Services to Prevent Entry of Diseases of Aquatic Animals
IV-1. Responsible Agency and Personnel
The decision maker regarding requests for importation of live aquatic animals is the Director General (DG) of the DOF. Quarantine decisions are made by the Director of Research and Development Division, DOF, while inspections are conducted by the Quarantine Inspection Section, DOF. Inspection on arrival at airport is conducted. The samples obtained at the airport are examined at the Quality Control Laboratory, Thaketa under the DOF. Levels II and III diagnosis are used.
IV-2. Procedures and Requirements for Importation and Exportation
a. Importers have to apply to the DG of the DOF. Import and export of live aquatic animals are decided by the DG with the approval of the Ministry after careful determination on whether the animal may cause environmental impact or has a positive effect on national economy.
b. When the live aquatic animals arrive, the authorized inspectors from DOF inspect health certificates and the live animals at the airport. If necessary, the samples are examined at the Quality Control Laboratory and Disease Section, Thaketa.
c. Laws and Regulations concerned with import/export of live aquatic animals have been included in the Laws Relating to Aquaculture. The DG is the only authorized person who can make decisions about importation and export of live aquatic animals.
d. Importers have to apply to the DG of the DOF. Exporters have to hold the Collection License at first and can apply to the Ministry of Commerce for export. An example of a Collection License and its accompanying instruction is in Annex I.
V. Research and Training of Fish Health Staff for Quarantine, Diagnosis, and Surveillance of Diseases of Aquatic Animals
a. Current research activities-Nil
b. List of agencies-Nil
c. List of publications
Disease Section (in local language)
d. Agencies Conducting Trainings on Diseases
Research and Development Division (DOF)
U Tin Win, Director
Tel: 095-01-211376, Fax: 095-01-228258
E-mail: DOF@mptmail.net.mm
e. Training Courses
1. Strengthening of Fish Disease Diagnosis (Mycology,
Virology, Bacteriology, Histopathology) (Japan, 1994)
2. Shrimp Health Management Training by NACA (Thailand,
1999)
3. Fish Health Management Training by SEAFDEC
(Philippines, 2000)
4. Aquaculture Health Management by SEAFDEC (Philippines, 2002)
5. PCR Training by Private Company Limited
(Thailand, 2002)
6. Hands-on Training for Important Viral Disease of
Shrimp and Marine Fishes by SEAFDEC (Philippines, 2002)
7. Second Hands-on Training for Important Viral Disease of
Shrimp and Marine Fishes by SEAFDEC (Philippines, 2003)
f. Training Needs
Specific trainings on basic diagnosis of parasites, virus, bacteria, fungus
on major culture species like, carps, prawns, shrimps, marine finfishes;
training on how to conduct surveillance, monitoring and diagnosis.
Annex 1. Example of a Collection License used in Myanmar
GOVERNMENT OF THE UNION OF MYANMAR MINISTRY OF LIVESTOCK AND FISHERIES DEPARTMENT OF FISHERIES
License No ...............
License for Collection and Marketing of Aquatic Products
In accordance with existing Laws and Instructions herewith attached,
the Director General of the Department of Fisheries, Ministry of Livestock
and Fisheries, issues this License.
1. (A) Name of applicant .......................................
(B) National
Registration.....................................
Card number
(C)Address........................................................
2. (A) Permitted Area
.............................................
(B) Permitted Kind
of..........................................
Aquatic Product
...........................................
(C) Quantity/
volume............................................
3. In terms of license duration, it starts the date of.............. and
shall end on the date of.....................................................
Issue Date
Director General
Department of Fisheries
Instructions
Current Status of Transboundary Fish Diseases in the Philippines: Occurrence, Surveillance, Research and Training
Simeona E. Regidor, Juan D. Albaladejo and Joselito R. Somga
Fish Health Section
Bureau of Fisheries and Aquatic Resources
860 Quezon Avenue, Quezon City, Philippines
I. Current Status of Koi Herpesvirus Disease (KHVD) in the Production of Common Carp and Koi Carp
I-1. Production of Common Carp and Koi Carp
a. Production of Common Carp
In 2003, production of common carp (Cyprinus carpio) was estimated at 667 metric tons (MT). Most of the production came from the provinces of Luzon particularly Rizal, Laguna, Quezon, Ifugao and Cordillera. The fish is commonly cultured in ponds and some in pens, mainly as monoculture and, to a lesser extent, polyculture with tilapia. Common carp production remains limited because of inadequate supply of fingerlings. Common carp was introduced from China in 1915. The fish was stocked in several lakes and rivers all over the country. In Luzon, it was introduced in Laguna de Bay, Bato and Baao in Bicol, Paoay Lake in Ilocos Norte, Lake Naujan in Mindoro, and Taal Lake. It was also introduced into Magat River in Nueva Viscaya, Lakes Bato and Buhi in Camarines Sur, and Cagayan River in Isabela. In Mindanao, it was introduced in Lakes Lanao, Mainit and Buluan. Since then, common carp has become prevalent in many rivers, lakes and reservoirs in the country. In the 1990s, the Bureau of Fisheries and Aquatic Resources (BFAR), through the National Inland Fisheries Technology Center (NIFTC) in Tanay, Rizal, in collaboration with Philippine Council for Aquatic and Marine Research and Development (PCAMRD), and the University of the Philippines Los Banos (UPLB), established common carp farming technology for the upland areas of Rizal, Laguna, Quezon, Ifugao and Cordillera. BFARNIFTC served as the main source of fingerlings, as well as other BFAR Centers and Stations situated in Luzon.
At present, BFAR is conducting research for the genetic improvement of
this species. The Department of Agriculture (DA) and BFAR boosted carp
productivity and has launched a national carp dispersal program by stocking
the new genetically-improved fingerlings in Laguna de Bay. This is a product
of successful intra-specific breeding of domesticated carp with three strains
from Indonesia and Vietnam: the Majalaya, Sukabumi and Vietnam strains.
It is also the potential species for other inland bodies of water such as Taal
Lake in Batangas, San Roque Dam in Pangasinan, Magat Dam in Isabela,
and Lanao Lake and Liguasan Marsh in Mindanao.
b. Production of Koi
There is limited information on koi production in the Philippines. The
Ornamental Fish Association of Southern Tagalog is producing koi for the
local market. In 2003, their production was about 1.5 million pieces. Another
six farms in Pila, Laguna produced about 300,000 koi last year. The BFAR
National Fisheries Biological Center (NFBC) is also into production of koi
with 50,000 koi were produced last year for the local market. However, the koi
they produce is not yet comparable with imported ones when it comes to quality.
There are also ornamental fish traders that import koi for local hobbyists.
These koi are usually stocked as ornamentals in concrete ponds in gardens.
According to importers, they usually import the best quality koi from Japan.
I-2. Koi Herpesvirus Disease (KHVD) of Common Carp and Koi
So far, KHVD has not yet been reported in the Philippines. When there
was an outbreak of mass mortalities of koi and common carp in Indonesia in
2002, BFAR issued a temporary suspension of carp importation in June of that
year and conducted a consultation with the aquarium fish traders, hobbyists
and concerned government agencies. It was unanimously agreed that koi should
be imported from Japan, where there was no reported KHVD at that time. The
importer's holding facility shall be inspected by BFAR prior to issuance of
import permit. The fish should be in quarantine for 15-30 days and the health
status monitored by a Fish Health Officer. However, after the KHVD outbreak
in Japan in October 2003, BFAR issued another temporary suspension for
importation of koi from all countries in January 2004. All BFAR regional offices
and centers were instructed to strengthen their reporting and monitoring of any
disease problems of common carp and koi in their area.
II. Current Status of Viral Diseases in the Production of Shrimps and
Prawns
II-1. Production of Shrimps
a. Production of Tiger Shrimp (Penaeus monodon)
The Philippines attained its highest shrimp production in 1994 with 90,000
MT, making it as the third largest producer in the world. From 1997 to
present, total production figures are almost similar (Fig. 1).
]Fig. 1. Philippine shrimp culture production and export, 1987-2003. Production figures
are in metric tons ´1,000.
Export figures vary from year to year. The overall production experienced
a steady decline starting in 1996 and this was attributed to the increasing
environmental degradation and disease problems, particularly luminous
vibriosis. This was further aggravated in 1999 with the appearance of white
spot syndrome virus (WSSV), first in intensive farms and then in extensive
farms in 2002.
Timely intervention of the national government particularly the DABFAR
started in 1996 through the formation of the inter-agency Task Force,
the Oplan Sagip Sugpo, whereby the recovery program for shrimp production
was set with immediate and long-term interventions. The program was
enhanced by the formation of the Shrimp Task Force in 2000 to undertake
the following tasks:
Source of Spawners, Broodstock and Postlarvae: Almost 90% of shrimp postlarvae originate from hatcheries, while supply for spawners and
broodstock rely mostly on capture fisheries and collectors from wild sources.
The remaining 10% of shrimp postlarval supply are wild-caught stocks
gathered from nearshore areas during its season for collection. Most of the successful hatchery operators are located in Western and Central Visayas
supplying 60% of the country's postlarval requirement. Traditional wild
spawner and broodstock collection sites are in the following areas:
Luzon: Quezon, Masbate
Visayas: Capiz, Negros, Bohol, Leyte
Samar: Surigao, Davao, Misamis Occidental, Zamboanga del Norte
Country of Origin of Imported Stocks: The only known importation of
P. monodon into the Philippines came from Thailand in 1992. This was made
by Dole Philippines for their production ponds in General Santos City,
Mindanao. This introduction prompted the Negros Prawn Producers
Marketing Cooperative, Incorporated (NPPMCI) to lobby for the passing
into law the prohibition of importation of any exotic shrimp species into the
country. Thus, in 1993, Fisheries Administrative Order (FAO) No. 189 was
passed. This was on the "Prohibition of the importation of all live stages of
shrimps and prawns". In 2001, this Order was amended by FAO No. 207
which includes the prohibition of the culture of imported exotic shrimp
species.
Live Export Records: As specified in FAO No. 143-5 and stated in "Amending Section 1, FAO No. 143-4", the exportation of live pond-raised prawns not more than sixty (60) grams per piece is allowed. Live marketable size black tiger shrimp (P. monodon) were exported in small quantities to Taiwan, HongKong and Thailand as part of the live fish trade to these countries.
b. Production of Pacific White Shrimp (Litopenaeus vannamei)
The Philippine government, through BFAR has been implementing a
total ban in the importation of live shrimps and prawn of all stages as early
as 1993 through FAO 189 that was further amended in 2004 to include not
just the importation, but also the culture of imported exotic shrimp species.
However, the lure of Pacific white shrimp culture resulted in illegal
importation of postlarvae of L. vannamei originating mostly from Kaoshiung,
Taiwan starting in 1998. The illegal shipment is technically smuggling exotic
species in the guise of milkfish fry (Chanos chanos). Approved permits
issued by BFAR for importation of milkfish fry were replaced with the fry of
L. vannamei. This can be gleaned from the series of confiscations conducted
in international airports.
To stop the rampant mis-declaration of live fish to these ports, the
following BFAR office directives were issued (see Box):
c. Production of Freshwater Prawn (Macrobrachium rosenbergii)
Commercial production of M. rosenbergii in freshwater ponds and riceprawn
culture systems was given a boost in 2001 after commercial prawn
fry production was achieved. The estimated production was 70 metric tons
with yearly increase of 10%. However, the bulk of production is still mainly
derived from wild caught fisheries with only 10% being contributed by
aquaculture. Increase in freshwater prawn aquaculture is promising since
new areas for grow-out production (pond and rice-prawn culture) are currently
being developed in Regions 1-8 and 11.
II.1. Diseases of Shrimps and Prawn
a. White Spot Syndrome Virus (WSSV)
Viral infections remain untreatable, thus exclusion is the most logical alternative to prevent their entry into culture facilities. This highlights further the need to screen for viruses using the most sensitive and specific method available. A DNA-based PCR protocol developed for WSSV by Tapay et al. (1999) has been reported to detect isolates of the virus from various geographic regions like China, Indonesia, Japan, the United States, and India.
Furthermore, the same protocol has been used extensively in testing for WSSV
in asymptomatic shrimp from hatcheries and grow-out ponds.
In February 2000, the first mortality associated with WSSV infection in
the Philippines was observed in cultured P. monodon in Negros Occidental.
The causative agent was confirmed as WSSV using PCR (Magbanua et al.,
2000).
Sixteen PCR laboratories are currently in place in strategic regional sites
conducting comprehensive monitoring and surveillance program. Most
postlarvae are checked for WSSV carrier status before shipment to various
islands within the country. In 2002, only 35 samples out of 1,115 analyzed
(3.14%) were confirmed positive for WSSV, but in 2003, a 5-fold increase in
WSSV positive samples was recorded (169 positive samples out of a total of
1,413.
Increased infection rate in 2003 was observed during the cold months of
the year starting in October. Mortality in ponds was noted in the months of
November to February, resulting to crop failure. In addition to previously
recorded infected areas, WSSV infection spread to other shrimp producing
provinces as such Davao del Sur, Camarines Sur, Iloilo, Capiz, Lanao del
Norte, Masbate, Sorsogon, Samar, Leyte, and Pangasinan.
The impact of WSSV infection is limited in magnitude and spread
compared with other countries due to the pro-active program instituted by
the Philippine government, through BFAR's "National Action Program to
Control WSSV in Shrimp". This program was conceived in March 2000,
with the following specific objectives and activities:
1. Exclusion
This approach aims to prevent further introduction of WSSV carriers
into the country. Since the most effective carriers of the virus are live shrimps
and crustaceans, a complete ban on importation of live shrimps, prawns and
other crustacean species is the logical preventive approach. This is
implemented by virtue of Fisheries Administrative Order No. 189.
A new FAO was drafted to strengthen FAO 189 to include not only
prohibition on the importation, but also the culture of imported live shrimp
and prawn of all stages. The draft was presented in a series of regional
consultations to various stakeholders, including the National Fisheries Aquatic
Resources Management Council (NFARMC) as mandated by Republic Act
8850 of 1998 or the New Fisheries Code. After deliberation and upon
endorsement of the Secretary of the Department of Agriculture (DA), Fisheries
Administrative Order 207 Series of 2001 was signed into law on 17 May 2001.
2. Containment
The containment approach seeks to prevent the spread of WSSV. As
much as possible, WSSV outbreaks should be contained within the areas
originally affected so that areas that are still WSSV-negative can be spared
from the potentially-devastating effect of the disease. The archipelagic nature
of the country and the fact that shrimps can, on their own, potentially move
from one part of the country to another makes this approach highly challenging. Towards this end, five major activities are being implemented,
namely:
a. Detection and diagnosis of WSSV;
b. Surveillance and reporting;
c. Regulation of in-country movement of live shrimps, particularly
postlarvae or fry stages;
d. Hatchery accreditation scheme; and
e. Promotion of environment-friendly shrimp farming and good farm
management practices.
These strategies are envisioned to help improve the quality of shrimp postlarvae being produced and marketed in the country, to raise awareness among hatchery operators on the importance of using healthy shrimp spawners, and to highlight to shrimp growers the importance of using only high-health shrimp fry for stocking in grow-out ponds.
3. WSSV Detection and Diagnosis
Detection of the disease is the most basic requirement for its effective
control. Thus, it was given highest priority by BFAR. Since PCR-based
diagnostic techniques are currently the most reliable diagnostic tools, BFAR
started a program in 2000 with disease surveillance as a focal point and
"early detection of the virus" using PCR as a prevention strategy. At present,
the BFAR has 16 PCR-capable facilities nationwide strategically located in
shrimp growing areas (Table 1).
Table 1. List of PCR-capable facilities
Aside from PCR, the laboratories are also equipped to undertake the following laboratory procedures:
1. Quantitative bacteriology;
2. Shrimp fry quality assessment; and
3. Water quality analysis.
PCR-based diagnosis is a sophisticated and precise technique that requires specialized training. Hence, a complimentary manpower capability-building on the operation of this specialized laboratory procedure was conducted for Regional Fish Health Officers and technicians from accredited private laboratories. Subsequently, on-site hands-on PCR trainings were also conducted with regular proficiency testing of the laboratory technicians to ensure good quality control standards. In order to standardize the PCR procedure, the National Institute of Molecular Biology and Biotechnology (BIOTECH) of the University of the Philippines in Los Banos and SEAFDEC Aquaculture Department were designated by BFAR as the national reference laboratories for WSSV. These laboratories insure that all diagnostic kits used in the PCR protocol are standardized to keep the integrity and reproducibility of the procedure, and they serve as depository of the virus materials for maintenance and safekeeping. Furthermore, they serve as the agencies to resolve conflict of results that might arise in the conduct of the analysis. Two non-government organizations, NPPMCI and BARFI, are also involved in the program in order to have participatory collaboration with the private sector by providing them with resources such as PCR equipment, training and technical support. These organizations are actively involved in the exchange of information and formulation of future strategies to control the spread of the viral diseases.
4. Surveillance and Reporting
Even prior to the formulation of the WSSV Control Program, BFAR has
been actively involved in the Quarterly Aquatic Animal Disease Reporting
System that has been adopted within Asia-Pacific region under the joint
programs of the Food and Agriculture Organization (FAO), Network of
Aquaculture Centers in Asia-Pacific (NACA) and Office International des
Epizooties (OIE). To support this, BFAR requires participating field
laboratories to submit monthly reports. Meanwhile passive surveillance in
areas not covered by the participating laboratories continues using the
National Aquatic Animal Disease Reporting format developed under the FAO/NACA/AusAid/APEC Project.
5. Regulation of in-Country Movement of Shrimp Fry
There is considerable movement of shrimp fry from one province to
another due to the demand from shrimp growers. To minimize spread of
disease, BFAR strengthened existing regulations covering in-country
movement of live shrimps which includes issuance of health certificate/permit, and inspection
procedures at ports of entries or origins. In addition,
protocols for proper disposal of WSSV-infected postlarvae and for
decontamination of WSSV-infected hatchery facilities will be prepared. The
following Fisheries Office Orders are in force to insure smooth
implementation:
a. Fisheries Memorandum Order No. 240, Series of 2003 concerning regulations on transboundary movement of shrimp postlarvae;
b. Fisheries General Memorandum Order No. 014, Series of 2004 containing the Guidelines for the Implementation of Fisheries Memorandum Order No. 240; and
c. Fisheries Memorandum Order No. 013, Series of 2004 is on imposition of active surveillance mechanism for all shrimp hatcheries nationwide as part of the strict implementation of the National Action Program to Control White Spot Syndrome Virus in shrimp. Continuing education and training of quarantine officers and laboratory technicians will be pursued on regular basis. Stakeholders in the shrimp industry, such as hatchery operators, shrimp fry traders and growers, will likewise be educated on the importance and benefits of compliance.
6. Shrimp Hatchery Accreditation Scheme
A Fisheries Administrative Order on rules and regulations for issuance
of Compliance Certification based on "best practice" in the hatchery was
presented for adoption by the Philippine Shrimp Hatchery Association
(PHILFRY). Comments and inputs from the deliberation were incorporated
in the final draft that was endorsed to the NFARMC for approval of the law.
7. Good Farm Management Practices
To augment the disease prevention strategies, promotion of good culture
practices and bio-security measures are being promoted in-farm. This is
based on the "Code of Practice for Sustainable Shrimp Farming". Also,
promotion of environment-friendly schemes in shrimp farming that have been
field-tested by SEAFDEC and BFAR through the Joint Mission for the
Accelerated Nationwide Technology Transfer Program will continue.
b. Taura Syndrome Virus (TSV)
Due to the existing ban on importation of exotic shrimp species in the
country, there are no reports of TSV infection in the Philippines. At present,
SEAFDEC is the only laboratory capable of testing for TSV. Samples
submitted to SEAFDEC Aquaculture Department obtained from illegal
shipments at airports showed negative results for the virus after analysis
using PCR. BFAR is planning to include active surveillance for TSV in its
monitoring program.
c. Significant and Emerging Viral Diseases of Macrobrachium
rosenbergii
Testing for important prawn viruses that might infect local population of
M. rosenbergii is now included in the National Action Program. Since
government and private hatchery operations to produce prawn postlarvae is
still inadequate, selective importation of postlarvae and broodstock was
allowed to augment the local supply for stocking in ponds, and for genetic
diversity and genetic selection programs. Special permits were issued by the Department of
Agriculture through the recommendation of BFAR to import
a specific number of prawn from Thailand and Lao PDR. All importations
were subjected to pre-border inspection from the country of origin by
recognized Fish Health laboratories using techniques to detect economically
important diseases of M. rosenbergii. Subsequent post-border inspection of
the shipment was also performed in the Fish Health Central Laboratory in
Manila.
III. Surveillance, Monitoring and Diagnosis of Diseases of Aquatic Animals
III-1. Responsible Facility and Personnel
The Fish Health Section (FHS) of BFAR spearheads the implementation
of monitoring of aquaculture farms, and provides diagnostic services as well
as technical and advisory assistance to the aquaculture industry. Its monitoring
program includes disease surveillance and reporting system, aquatic animal
health certification and implementation of quarantine procedures, assessment
of the health status of stocks of selected fish, and management of other aquatic
resource farms in the Philippines.
The FHS operates a Central Fish Health Laboratory with the responsibility
and competence for ensuring or supervising the implementation of the aquatic
animal health measures recommended by the OIE and European Commission
Directive 2003/858/EC. The FHS develops standardized routine procedures
and guidelines for the operation of the 15 Regional Fish Health Laboratories
(Fig. 2), supervises the activities, and sets directions for the operation of
such laboratories, as well as provides technical guidance to 38 Regional
Fish Health Officers (FHOs) on the execution of diagnostic activities and
technical assistance on fish health-related problems. It also imparts
specialized training programs on fish health for government fishery biologists,
extension workers and fish farmers.
Surveillance and monitoring program of farms for diseases and drug
residue monitoring was developed to know the animal health situation in
the Philippines and in compliance with the requirements of trading partners.
As exporter of fresh and frozen aquaculture products to European
communities, the FHOs also implement disease monitoring and surveillance
in fulfillment to the requirements of EC Directive 2003/858/EC. The FHOs
also act as fishery inspectors authorized to certify fish products of aquaculture
origin for export into the European Community for human consumption.
a. Regional Fish Health Laboratories
As indicated in Fisheries Office Order No. 211 series of 2003 issued on
28 August 2003, the FHOs shall be responsible for the implementation of
residue monitoring report and plan in accordance with European Union
Council Directive 96/23/EC in their area of responsibility and perform the
following functions: a) assist in planning, directing, and implementing of
Fig. 2. Map of the Philippines showing the location of the Regional Fish Health Laboratories
the national program on fish health management; b) supervise and operate
the RFHLs and satellite laboratories in their respective areas of jurisdiction; c) adopt FAO 220, series of 2001 concerning
"Operation of the Fish Health
Laboratories and Collection of Fees and Charges"; d) conduct fish kill
investigation and implement the National Strategy on Fishkill Investigation,
Reporting and Prevention; e) provide technical support to the fish inspection
and quarantine services; f) act as quality control officer on the regulation of
animal feed veterinary drugs and products in aquaculture; and g) submit
quarterly accomplishment reports relating to program to the Bureau Director.
b. National Disease Monitoring and Surveillance
Table 2 lists the central and regional FHOs. The Central Fish Health
Laboratory provides the technical know-how and formulates mechanisms to
coordinate the conduct of disease surveillance, monitoring, and reporting.
To harmonize activities on disease surveillance, a monitoring form was
developed for field use. Quarterly reports are submitted to the Central Fish
Health Laboratory for information and consolidation.
In 2003, disease surveillance and monitoring of 199 shrimp, 80 milkfish
and 336 tilapia farms nationwide were conducted (Table 3). No major disease outbreaks were observed in these farms. Shrimp hatcheries were encouraged
to screen their fry for WSSV and to conduct fry quality assessment prior to
stocking to lessen the risk of disease outbreak.
Table 2. List of Fish Health Officers of the Bureau of Fisheries and Aquatic Resources
III-2. Diagnostic Capabilities and Major Diseases of Aquatic Animals
The laboratories that conduct fish disease diagnosis and their corresponding level of diagnosis are listed in Table 4. Following are the levels of diagnosis: Level I: diagnostic activity limited to observation of animal and the environment, and clinical examination (on-site or field diagnosis); Level II: diagnostic activity includes parasitology, bacteriology, mycology and histopathology (laboratory diagnosis); and Level III: diagnostic activity includes virology, electron microscopy, molecular biology, and immunology (laboratory diagnosis).
a. Economically-Important Diseases in the Philippines
Significant disease outbreaks that caused mass mortalities of wild and
cultured fish stocks are listed in Table 5. Aphanomyces invadans, a fungus, in
association with Aeromonas hydrophila caused mass mortality of wild
populations of Clarias batrachus, Ophicephalus striatus and Mugil cephalus.
The outbreak started in 1985 in Luzon and was recently reported in Lake
Lanao. Epizootic Ulcerative Syndrome (EUS) was confirmed by the presence
of fungal hyphae in tissue sections of Glosogobius guirius caught in the lake.
Reports from Roxas City in Panay Island of mortality caused by parasitic
diseases like monogeneans on the body surface and gills of fry of brown
spotted grouper were received. It was reported that outbreaks are also
occurring in Mindoro and Palawan, the sources of grouper fry. Another
parasite, Caligus epidemicus, caused mass mortality of tilapia and milkfish
cultured in brackishwater farms in Negros Occidental, Zambales, Bicol and
Pagbilao, Quezon. One more parasite, an isopod identified as Corallana
grandiventra, has been the cause of losses among tilapia cultured in cages at
Taal Lake, a freshwater lake. Mortality of up to 100% was reported causing
some fish farmers to cease operation.
Diseases outbreaks in P. monodon caused by Vibrio spp. have been
associated with mass mortalities. Aeromonas hydrophila has been reported
in fish mortalities associated with Aphanomyces invadans in EUS-infected
fish.
b. Current Needs and Requirements
Although disease and drug residue surveillance and monitoring are in
place, the activities need a lot of improvement. At the moment, project
proposals are in the pipeline to upgrade the existing capacity and capability
of BFAR Fish Health Section. There is a need to develop a proposal on
quarantine, including a national program on monitoring and surveillance of
emerging diseases such as, but not limited to, TSV, KHV and viral nervous
necrosis (VNN). Assistance is also very much needed to implement the
Technical Implementing Guidelines on Asia Regional Technical Guidelines
on Health Management for Responsible Movement of Live Aquatic Animals
and the Beijing Consensus and Implementation Strategy.
IV. Quarantine Services to Prevent Entry of Diseases of Aquatic Animals
IV-1. Responsible Agency and Personnel
a. Laws and Regulations
BFAR is the government agency responsible for the implementation of
fisheries inspection and quarantine services as mandated by Republic Act 8550,
section 67. Implementing rules and regulations are issued in the form of
Fisheries Administrative Orders to properly implement the law. For the
transboundary movement of live fish and fishery/aquatic products, the FAO
No. 221, Series of 2003 was enacted. It contains the implementing rules and
regulations pertaining to the importation of live fish and fishery/aquatic products
to include microorganisms and bio-molecules. The following are the relevant
documents for implementation of the movement of live aquatic animals:
a) Fisheries Administrative Order No. 220, Series of 2001 pertains to
the operation of Fish Health laboratories and collection of fees and
charges therefore;
b) Fisheries Administrative Order No. 207, Series of 2001 prohibits
the importation and culture of imported live shrimp and prawn of all
stages;
c) Fisheries Administrative Order No. 221, Series of 2003 regulates
further the importation of live fish and fishery/aquatic products under
FAO No. 135 Series of 1981 to include microorganisms and biomolecules;
d) Fisheries Office Order No. 211, Series of 2003 is an amendment to
Fisheries Office Order No. 147-01, Series of 2001 and pertains to
designation of Regional Fish Health Officers;
e) Fisheries Memorandum Order No. 240, Series of 2003 pertains to
Regulations on Transboundary Movement of Shrimp Postlarvae;
f) Fisheries Memorandum Order No. 078, Series of 2003 pertains to
Restriction on Entry of Live Fish Species Importation from Taiwan
and China;
g) Fisheries General Memorandum Order No. 014, Series of 2004 are
Guidelines for the Implementation of Fisheries Memorandum Order
240; and
h) Fisheries Memorandum Order No. 013, Series of 2004 pertains to
the imposition of active surveillance mechanism for all shrimp
hatcheries nationwide as part of the strict implementation of the
National Action Program to Control White Spot Syndrome Virus (WSSV) in shrimp.
b. Responsible Facilities and Location
There are two sections in BFAR that have responsibility over the
movement of live aquatic animals: the Fish Health Section under the Office
of the Director, and the Foreign Trade and Miscellaneous Permit Section
under the Fisheries Regulatory and Quarantine Division.
The Fish Health Officers and the Fisheries Quarantine Officers (FQOs)
implement the health management process as defined in the Asia Regional
Technical Guidelines on Health Management for Responsible Movement of
Live Aquatic Animals and the Beijing Consensus and Implementation
Strategy. The FHO implements the pre-border (exporter) and post-border
(importer) activities, and the FQO is concerned with border activities in the
transboundary movement of live aquatic animals. Table 6 lists the Fisheries
Quarantine Officers.
c. Conduct of Quarantine and Inspection Services
As outlined in FAO 221, all importation of live fish and fishery aquatic
products, aquatic microorganisms, bio-molecules, including genetically
modified organisms (GMOs) and endangered species will be categorized by
BFAR, in cooperation and coordination with the Bureau of Plant Industry,
Bureau of Animal Industry, and Protected Areas and Wildlife Bureau into
the following: low risk species, medium risk species, high risk species, and
prohibited or banned species.
IV-2. Procedures and Requirements for Importation
a. Filing
The importer must show intention to import live fish and fishery/aquatic
products including microorganisms and bio-molecules through the filing of
his application at least five working days prior to the importation of low risk
species, and 10 to 15 days for medium risks species. The decision whether or not to import high risk species will be given thirty (30) days after evaluation
of the proposal and other documents which may be required by the Import
Risk Analysis (IRA) Panel.
b. Review by Import Risk Analysis Panel
All importation is subject to review by the IRA Panel that shall serve as
the secretariat and clearing house of all IRA cases and may tap a group of
experts to resolve individual cases whenever necessary. The panel shall be
chaired by a Fish Health Officer and has five permanent members who shall
have the following minimum qualifications: a) one member shall be a member
of the Philippine Bar; b) one member shall be a fish health officer; c) one
member shall be a regulatory fisheries quarantine officer; d) one member
shall be a member of NFARMC; and e) one member shall be a fishery
biologist (on call, depending on the required expertise). The importation
requirements are dependent on the category of the commodity which will be
listed in the permit issued by BFAR (Section 7 FAO 221).c. Importation Requirements According to Section 7 of FAO No. 221
1) For low risk species - duly accomplished form. Risk analysis shall not be required except when there is a reported significant outbreak in the county of origin.
2) For medium risk species
i. Duly accomplished application form;
ii. Duly accomplished proposal form with emphasis on health,
ecological and genetic impacts of the proposed importation;
iii. Import risk analysis (IRA) by the IRA Panel;
iv. Health Certificate from the competent authority of the country of
origin to be presented upon arrival; and
Table 6. List of Fisheries Quarantine Officers
v. The quarantine and inspection requirements shall be based on the decision of the BFAR IRA Panel which may require a quarantine period of 24-28 days on a case to case basis after the release of the shipment from the airport to the BFAR quarantine facility, with costs to be borne by the importer.
3) For high risk species
i. Duly accomplished application form;
ii. Duly accomplished proposal form with emphasis on health, ecological
and genetic impacts of the proposed importation;
iii. Import risk analysis by the IRA Panel;
iv. Health certificate from the competent authority of the country of
origin to be presented upon arrival of the consignment at the NAIA
or other designated ports of entry. On a case to case basis, BFAR
may specify certification requirements for individual species and/or
shipments to ensure freedom from specified diseases as deemed
necessary; and
v. Quarantine and inspection until the first generation (F1) offspring. This
will be imposed after release of the shipment from the airport to the
BFAR quarantine facilities, with costs to be borne by the importer.
d. Inspection
For security purposes, live fish and fishery/aquatic products are subjected to
inspection requirements upon arrival at the NAIA, the only allowed point of
entry for live fish and fishery/aquatic products. The importer is required to submit
documents (original copy of the import permit, photocopies of pro-forma invoice,
packing list, and airway bill or bill of lading) to the BFAR Fisheries Quarantine
Officer.
For medium and high risks species, a copy of health certificate is required.
Consignments not accompanied by import permit and/or health certificate shall
be confiscated and destroyed. The Fisheries Quarantine Officer shall check the
species identity and conduct visual inspection. If the fish is clearly unhealthy, the
quarantine officer will require treatment of the shipment in the importer's holding
facility under the supervision of a fish health officer. If the unhealthy fish poses
high risk of contaminating healthy stocks, the shipment shall be confiscated and
destroyed. Laboratory examination of samples obtained from the shipment shall
be conducted by the BFAR Fish Health Officer at the expense of the importer.
IV-3. List of Quarantinable Diseases of Aquatic Animals in the Philippines
The Philippines uses the existing list in the Quarterly Aquatic Animal Disease Report (Asia and the Pacific) jointly published by NACA and FAO, and the list of diseases in the International Aquatic Animal Health Code of the OIE.
V. Research and Training of Fish Health Staff for Quarantine, Diagnosis and Surveillance of Diseases of Aquatic Animals
a. Current Research Activities
Most of the researches on diseases of fish are being implemented by the
Southeast Asian Fisheries Development Center. Table 7 shows the list of agencies,
departments and universities doing research on fish disease in the Philippines.
Table 7. List of the agencies, departments, and universities that conduct fish disease research
b. Recent Publications on Viral Diseases of Fishes and Shrimps
Following are the publications on viral diseases from 1998-2003:
c. Training and Training Needs
There are two agencies that conduct fish disease training in the
Philippines. SEADEC Aquaculture Department conducts training for local
and international participants such as AquaHealth Online, an internet-based
training, and hands-on training for important viruses affecting fish and shrimp.
BFAR conducts trainings for Fish Health Officers and Fishery Quarantine
Inspectors, as well as private participants.
The Fish Health Staff of BFAR has availed of training programs on
quarantine, fish disease diagnosis, and surveillance developed by the
International Development Council (IDRC) of Canada, Network of
Aquaculture Centers in Asia-Pacific (NACA), Food and Agriculture
Organization of the United Nations (FAO), Aquatic Animal Health Research
Institute (AAHRI), and the Southeast Asian Fisheries Development Center
(SEAFDEC). Likewise, the Fisheries Quarantine Officers at NAIA have
availed of the training programs developed by BFAR-Fish Health Section,
SEAFDEC, NACA and FAO.
With increasing risks of spread of transboundary pathogens and diseases,
there is a need to enhance the diagnostic capability for TSV, KHV, and other
important diseases for the Fish Health Officers in the laboratory and for the
Fishery Quarantine Officers at ports of entry.
References
Magbanua PO, Natividad KD, Migo VP, Alfafara CG, de la Pena FO, Miranda
RO, Albaladejo JD, Nadala Jr ECB, Loh PC, Tapay LM. 2000. Prevalence
of white spot syndrome virus (WSSV) in cultured Penaeus monodon in
the Philippines. Dis. Aquat. Org. 42:77-82.
Tapay LM, Nadala CB, Loh PC. 1999. A polymerase chain reaction protocol
for the detection of various geographical isolates of white spot virus. J.
Virol. Methods 82: 39-43.
Current Status of Transboundary Fish Diseases in Singapore: Occurrence, Surveillance, Research and Training
Ling Kai Huat1, Susan
Kueh2 and Poh Yew Kwang3
Agri-Food and Veterinary Authority of Singapore
1Aquaculture Services Centre, Aquaculture Branch, Sembawang Research Station
Lorong Chencharu, Singapore 769194
2Aquatic Animal Health Branch, Animal & City Veterinary Laboratory
60 Sengkang East Way, Singapore 548596
3Wildlife Regulatory Branch, Sembawang Research Station,
Lorong Chencharu, Singapore 769194
Introduction
Any significant disease of aquatic animal such as koi herpesvirus (KHV)
and spring viremia of carp virus (SVCV) is of concern to Singapore. Import
and export of ornamental fishes in Singapore are carried out by licenced traders
under the Accredited Ornamental Fish Exporters Scheme (AOFES). Under
this Scheme, the exporters have to get their premises approved according to
guidelines set by the Agri-Food and Veterinary Authority of Singapore (AVA),
which include the provision of designated quarantine area, packing area and
disease treatment area. These approved premises are inspected monthly by AVA inspectors. As part of routine fish disease surveillances conducted by
AVA, regular fish samples are taken from each exporter premise once every
six months for laboratory examinations in the absence of any significant
disease. Additional samples are taken for laboratory examination should any
significant disease outbreaks occur in these premises. Any significant results
from these surveillances are reported in the Quarterly Aquatic Animal Disease
Report (Asia and Pacific Region), which is submitted to the OIE and NACA.
Since surveillance for KHV started in January 2003, no positive cases have
been detected to date.
There are 68 ornamental fish farms and 103 ornamental fish exporters in
Singapore. The local farms produced about 44% of the total export with a
value of S$72.8 million (US$42.3 million) in 2003. Shrimp farming is not
popular in Singapore and there are only 2 shrimp farms using traditional earthen
ponds for culture of tiger shrimp and Pacific white shrimp. The farms apply
intensive culture system with regular water exchanges. Total annual production from these two farms is about 100 metric tons (MT). So far there is no report
of white spot syndrome virus (WSSV) and Taura syndrome virus (TSV) of
shrimps in Singapore.
I. Current Status of Koi Herpesvirus Disease (KHVD) in the Production of Common Carp and Koi
I-1.Production of Common Carp and Koi
a. Production of Common Carp
Owing to very small market demand of common carp, there is no commercial farming of common carp in Singapore. There is limited number of wild common carp thriving in reservoirs and lakes in Singapore. These are for leisure and to control pest and not for human consumption. No export record of the species to other countries exists. Singapore imported less than 50 MT of common carp yearly for the last 3 years, mainly from Malaysia, for use in offerings during various special festivals. Data for the past 3 years are summarized in Table 1.
Table 1. Import of live common carp in Singapore for 2001-2003
b. Production of Koi
There are 4 koi farms and 40 koi importers and exporters in Singapore.
The activities of koi farms are mainly in the import of fingerlings and nursing
them into bigger size for local sale or export. The koi farms also provide hotel
services for koi hobbyists. The local production is negligible. Importers and
exporters with holding and quarantine facilities, import fish from different
sources, quarantine them for a period of 3 weeks, or hold them for a longer
period before exporting to other countries. The sources of spawners, broodstock
or fingerlings are Japan, Malaysia, Thailand, and China.
The import figures of koi for the last 3 years are shown in Figures 1- 4. The
main supplier of koi to Singapore is Malaysia, which supplied more than 90%
of the total quantity imported. This is followed by Japan (about 2 %) and China
(1.5%).
Singapore exports about 2.4 million pieces of koi annually to other countries.
The major importers of koi from Singapore are the United Kingdom, Germany,
United States and Malaysia. Export figures for the past 3 years are summarized
in Figures 5-8.
I-2. Koi Herpesvirus Disease (KHVD) of Common Carp and Koi
Presently, Singapore is free from KHVD. Since reports were made on KHVD as a significant disease of koi in Israel, Europe and United States in 1998, and the occurrence of koi mass mortality syndrome in Indonesia in 2002, ornamental fish traders dealing with koi in Singapore have been showing concern over this emerging disease. To address the concerns, AVA held a dialogue session with the Singapore koi traders in June 2003 in order to maintain industry awareness of the disease and to promote measures to prevent import and export of KHVD-infected fish. Since the reports of KHVD outbreak in Japan in October 2003, AVA has instituted compulsory inspection, testing and quarantine of all koi consignments imported from Japan and Indonesia. Quarantine is for a minimum period of 3 weeks. Koi samples from a particular consignment, or sentinel koi, are cohabitated with imported koi, and are subjected to testing for KHV by tissue culture. Only koi that tested negative for KHVD will be released from quarantine. KHVD-positive koi consignments are to be destroyed, and the premises disinfected accordingly.
II. Current Status of Viral Diseases in the Production of Shrimps and Prawns
II-1. Production of Shrimps
a. Production of Tiger Shrimp (Penaeus monodon)
There are only two shrimp farms in Singapore and they using traditional earthen ponds to culture tiger shrimp. The farms apply intensive culture system with regular water exchange. Below is the annual production for the last 3 years:
Year Quantity (MT)
2001 106.00
2002 91.82
2003 31.33
There was a drastic decrease in production in year 2003. As a result, one of the shrimp farms adopted crop rotational farming practice and switched to culture seabass in 2003. The spawners, broodstock and postlarvae are imported from Malaysia. Presently, no live export record to any country exists for shrimp and production remains not sufficient for local demand.
b. Production of Pacific White Shrimp (Litopenaeus vannamei)
There are only 2 shrimp farms in Singapore using traditional earthen ponds to
culture of Pacific white shrimp L. vannamei. Annual production for the last 3
years is tabulated below:
Year Quantity (MT)
2001 8.00
2002 23.00
2003 15.70
The sources of postlarvae is mainly Taiwan and China.
c. Production of Freshwater Prawn (Macrobrachium rosenbergii)
There is no freshwater prawn culture activity in Singapore and a small quantity of freshwater prawn is imported from Malaysia and Thailand for local consumption.
II-2. White Spot Syndrome Virus (WSSV)
There is no recent report on WSSV in Singapore.
II-3. Taura Syndrome Virus (TSV)
There has been no report of TSV in shrimp culture in Singapore.
III. Surveillance, Monitoring and Diagnosis of Diseases of Aquatic Animals
III-1. Responsible Facility and Personnel
The contact persons and responsible facilities that conduct diagnosis and
inspection services are the following:
(i) Aquatic Animal Health Branch, Central Veterinary Laboratory
60 Sengkang East Way, Singapore 548596
Email: susan_kueh@ava.gov.sg
(ii) Aquaculture Services Centre, Aquaculture Branch
Sembawang Research Station, Lorong Chencharu, Singapore 769194
Email: ling_kai_huat@ava.gov.sg
(iii)Epidemiology and Surveillance Branch
Email: Chang_Siow_Foong@AVA.gov.sg
(iv)Wildlife Regulatory Branch, Import & Export Division
Email: Poh_Yew_Kwang@AVA.gov.sg
These facilities conduct surveillance and monitoring for diseases of aquatic animals regularly.
III-2. Diagnostic Capabilities and Major Diseases of Aquatic Animals
a. Definition of Levels of Diagnosis
Level I: Diagnostic activity limited to observation of animal and the
environment, and clinical examination (On Site or Field
Diagnosis).
Level II: Diagnostic activity includes Parasitology, Bacteriology,
Mycology, and Histopathology (Laboratory Diagnosis).
Level III: Diagnostic activity includes Virology, Electron microscopy,
Molecular biology and Immunology (Laboratory Diagnosis).
Based on the classification, there are laboratories that can conduct Level II and III diagnosis.
b. List of All Economically-Important Diseases of Aquatic Animals
IV. Quarantine Services to Prevent Entry of Diseases of Aquatic Animals
IV-1. Responsible Agency and Personnel
The responsible facilities for quarantine of aquatic animals are the following:
(1) Wildlife Regulatory Branch, Agri-Food and Veterinary Authority of
Singapore
(2) Epidemiology and Surveillance Branch, Agri-Food and Veterinary
Authority of Singapore
(3) Aquaculture Services Centre, Agri-Food and Veterinary Authority of
Singapore
Quarantine and inspection are carried out at the importer's premises when
live aquatic animals arrive in the country. The responsible persons conducting
quarantine and inspection services are:
(1) Mr Poh Yew Kwang
(2) Mr Iyu Ching Ka
(3) Mr Teo Siang Hong
Levels I and II diagnosis are employed at quarantine stations.
IV-2. Procedures and Requirements for Importation
Licensed importers from Singapore must apply for an inward declaration permit for an incoming consignment. Based on the species declared during permit application, certain species such as koi from specified countries can only be imported on the condition that the fish are quarantined at the importer's premise upon arrival and a sample from the consignment must be submitted to the inspecting officers for lab analyses stipulated by AVA. The importers are to quarantine the fish pending outcome of the lab tests. On the day of arrival, there will be a follow-up inspection by AVA officers, as well as collection of samples from the newly imported batch for lab testing on specific diseases, e.g. koi herpesvirus. This activity is covered by law under the Singapore Animals and Birds Act, but no certificates are currently required.
IV-3. List of Quarantinable Diseases of Aquatic Animals
a. Viral diseases: SVCV, KHVD
b. Bacterial diseases: none
c. Fungal diseases: epizootic ulcerative syndrome (EUS)
d. Parasitic diseases: none
e. Other diseases: none
V. Research and Training of Fish Health Staff for Quarantine, Diagnosis, and Surveillance of Diseases of Aquatic Animals
Current research is geared towards establishment of diagnostic tests for
aquatic animal disease agents. Research is conducted at local universities and
polytechnic schools. Significant fish disease work is conducted at the National
University of Singapore. Following are major publications on viral diseases
of fishes and shrimps:
Gibson-Kueh S, Netto P, Ngoh GH, Chang SF, Ho LL, Qin QW, Chua FHC,
Ng ML, Ferguson HW. 2003. The pathology of systemic iridoviral disease
in fish. J. Comp. Pathol. 129:111-119.
Chang SF, Ngoh-Lim GH, Kueh LFS, Qin QW, Seng EK, Sin YM. 2002. Initial investigations into two viruses isolated from marine food fish in Singapore. Veterinary Record 150:15-16.
Chang SF, Ngoh GH, Kueh LFS, Qin QW, Chen CL, Lam TJ, Sin YM. 2001. Development of a tropical marine fish cell line from Asian seabass (Lates calcarifer) for virus isolation. Aquaculture 192:133-145.
Training on Fish Diseases are conducted by the following:
(1) Aquaculture Services Centre, Sembawang Research Station, Lorong
Chencharu, Singapore 769194
(2) Aquatic Animal Health Branch, Central Veterinary Laboratory, 60
Sengkang East Way, Singapore 548596
Topics covered in these training are on basic animal health course. Responsible personnel have gained experience from local and overseas seminars/workshops, and have earned postgraduate degrees. In order to support the needs for surveillance, monitoring and diagnosis, an inter-laboratory and agency attachments are necessary to disseminate and enhance hands on experience.
Current Status of Transboundary Fish Diseases in Thailand: Occurrence, Surveillance, Research and Training
Somkiat Kanchanakhan
Disease Control and Diagnosis Research Unit
Inland Aquatic Animal Health Research Institute
Department of Fisheries, Jatuchak, Bangkok 10900
Thailand
Introduction
Movement of live aquatic animals has been generally recognized as an
activity coupled with high risk of transferring diseases and pathogens from
one area to another. A review from a scientist indicated that international
fish trade has spread diseases to many countries for years (Hastein, 2000).
In case of Thailand, an introduction of Chinese carps (Hypopthalmichys
molitrix, Ctenopharyngodon idellus, Aristichthys nobilis) for food fish culture
in the past also introduced the parasite Lernaea into the aquatic ecosystem.
Importation of ornamental fishes also introduced many new pathogens such
as Hexamita, Tetrahymena, and Ranavirus. Some pathogens have wide host
ranges including food fish and ornamental fish. The susceptible hosts exhibit
clinical signs, disease and death. However, resistant hosts or fish that has
recovered from the disease will possibly serve as reservoir or carriers of the
disease. Awareness of aquatic animal disease spread through international
trade has been increasing since the first edition of Aquatic Animal Health
Code was published by the Office International des Epizooties (OIE) in 1995.
As part of the regional effort to control disease in aquatic animals, the
"Thailand National Strategy for Control of Aquatic Animal Diseases" have
been developed after seminars among staff of the Department of Fisheries
(DOF), Department of Livestock Development, universities, private sector
representatives and farmers were held in Bangkok in May 2001.
The components of the national strategic plan are as follows: (1) law
and legislation; (2) import/export regulation; (3) disease surveillance,
monitoring and control systems; (4) aquatic animal diseases, research and
development; (5) diagnosis units and capability building; (6) technology/
knowledge transfer; (7) public awareness; (8) contingency plan to control
disease outbreak; and (9) funding support. The strategic plans have been
implemented with good progress.
I. Current Status of Koi Herpesvirus Disease (KHVD) and in the
Production of Common Carp and Koi
I-1. Production of Common Carp and Koi
There are 3 culture systems for common carp: pond, ditch and cage systems. For pond culture system, farmers normally raise the carp with other fish species (poly-culture system) or with other animals (integrated culture system). For paddy-field culture system, farmers culture carp in the rice paddy fields during the rice cropping season. For ditch culture system, carp is cultured in the ditch that supplies water to fruit farms. According to Fishery Statistics Analysis and Research Group (2001), the total number of freshwater aquaculture farms recorded in Thailand is 389,374 (pond culture = 355,624 farms; paddy field culture = 14,829 farms; ditch = 7,165 farms, cage culture 1,207 farms). The total freshwater aquaculture production is 279,696 metric tons (MT) valued at 9,279.8 million Baht. There were approximately 17,465 common carp culture farms (pond culture = 15,693 farms; paddy-field culture = 1,723 farms; ditch culture = 49 farms) recorded in year 2001. Ninety percent of common carp farms used pond culture system and there was no record of common carp cage culture in Thailand in 2001. The common carp production in year 2001 was 4,773 MT (pond culture = 4,026 MT; paddyfield culture = 736 MT, ditch culture = 10 MT) valued at 146,658 Baht. The common carp can now be found in the wild (canals and rivers). There is no statistical record for wild caught carp since the quantity and value is very low. Generally, fish farmers obtain carp seeds from government or private hatcheries. Thailand introduced common carp from China about 100 years ago. There is no record of common carp exportation out of Thailand. The common carp is popular among the Chinese for consumption. The pituitary glands of common carp are used to artificially induce gonadal maturation and spawning in fish hatcheries. In the past 20 years, the pituitary gland of carp is in high demand in fish hatcheries. However, since the supply of synthetic hormones became common and gave similar stimulation on gonad maturation, the demand for pituitary gland of carp reduced. Koi production in Thailand increased in the past 3-5 years. Since Thailand is located in the tropics and the average water temperature is warm throughout the year, Koi rapidly grow and have relatively lower risk against cold-water diseases such as spring viraemia of carp virus (SVCV) and koi herpesvirus (KHV). Koi are cultured in earthen ponds, concrete ponds and cages. The koi brooders are from local sources as well as imported from Japan. Thailand exports koi to many countries. Since the outbreak of SVCV in China, and KHV in Indonesia and Japan, koi exportation from Thailand to other countries is getting higher.
I-2. Koi Herpesvirus Disease (KHVD) of Common Carp and Koi
Thailand started its KHVD monitoring program since August 2002 and is still free from KHVD up to now. The DOF also developed a rapid response team and gave high priority to investigate any disease cases reported by the fish farmers or by the fishery officers related to mass mortality or unusual death of koi. At the moment, KHVD survey is being conducted using virus isolation in KF-1 and BF2 cell lines, and through PCR detection.
II. Current Status of Viral Diseases and in the Production of Shrimps and Prawns
II-1. Production of Shrimps
a. Production of Tiger Shrimp (Penaeus monodon)
Tiger shrimp culture can be classified as extensive, semi-intensive and intensive culture systems. The number of farms and the amount of productions are shown in the Tables 1-2. Tiger shrimp brooders are collected from the wild in the Andaman Sea, Gulf of Thailand and South China Sea. Live exportations of marketable size shrimps were mainly to Hong Kong for human consumption.
b. Production of Pacific White Shrimp (Litopenaeus vannamei)
The Pacific white shrimp was introduced between March 1, 2002 and
February 28, 2003. The Pacific white shrimp farms are mainly of intensive
culture type. The most recent fishery statistics of the DOF covers up to year
2001 only. However, during the year 2002-2003, white shrimp production
is estimated to reach 40% of the total culture shrimp production of the country
or 120,000 MT. Pacific white shrimp brooders imported from the USA were specific-pathogen-free (SPF). Some illegal importation of brooders and
various stages of white shrimp have been recorded as originating from Taiwan
and Malaysia.
c. Production of Freshwater Prawn (Macrobrachium rosenbergii)
According to the Fishery Statistics Analysis and Research Group (2001),
there were 2,627 giant freshwater prawn culture farms in year 2001. The
giant prawn production during year 2001 was 13,310 MT valued at 1,587
million Baht. The prawn brooders were mainly collected from the wild and
culture ponds within the country. Both government and private hatcheries
Table 1. Number of shrimp farms by type of culture from 1997-2001
supply the prawn postlarvae to farmers. There is no record of giant freshwater prawn importation into Thailand.
II-2. White Spot Syndrome Virus (WSSV)
An outbreak of WSSV first occurred in Thailand in 1993 and caused losses of over US$500 million. WSSV usually causes problem in shrimp farms during the dry season in Thailand (November to February). Normally during the dry period, the water salinity is high and induces stress to cultured shrimps resulting in severe infection with WSSV. Viruses may come from different sources such as infected postlarvae, carriers and contaminated water. The extreme environmental changes in pH, temperature and salinity can trigger the virulence of the WSSV infection. The DOF has 11 laboratory facilities with the capability to detect viruses using polymerase chain reaction (PCR) to service to the shrimp farmers and screen shrimp postlarvae prior to stocking in the ponds. Of a total 22,235 samples that had been tested, 513 samples were recorded as PCR positive or about 2.5%. The positive samples were recommended for destruction by using disinfectants.
II-3. Taura Syndrome Virus (TSV)
TSV was first reported in Central America and Latin America in 1991 with losses reaching over 1,000 million US$. Pacific white shrimp with sizes between 0.1 - 5 g are most susceptible to the disease. TSV also infects many species of shrimp including P. stylirostris, P. aztecus, and P. setiferus. Affected areas recorded in the Americas are Ecuador, Peru, Columbia, El Salvador, Guatemala, Brazil, Nicaragua, Hawaii, Florida and Mexico. In 1999, TSV appeared and caused severe mortality to Pacific white shrimp cultured in Taiwan. For Thailand, the DOF had given temporary import permit of Pacific white shrimp for one year (March 2002-February 2003). During that time, 97,752 SPF shrimp brooders were imported into the registered hatcheries. Since Thailand has over 2,000 km of shoreline and is connected by land to nearby countries, there were some illegal importations of Pacific white shrimp. Because of un-controlled shipments, Thailand experienced TSV outbreak for the first time in year 2003. The TSV diagnosis had been confirmed at the Inland Aquatic Animal Health Research Institute (AAHRI) using RT-PCR and gene sequencing. Since then, TSV has established in the shrimp farms and hatcheries. The TSV survey during January-March 2004 showed that 21 of 561 (3.7%) shrimp samples from hatcheries and grow-out farms were tested positive for the virus. The positive batches of postlarvae were not allowed for stocking in grow-out farms. The contingency plan to eradicate TSV infected shrimp or disease carrier shrimp in the ponds or grow-out farms has been drafted and intensively discussed in the DOF.
II-4. Significant and Emerging Viral Diseases of Macrobrachium rosenbergii
There is no record of viral disease in giant freshwater prawn in Thailand.One viral research project is being planned to re-investigate the white muscle syndrome of the giant freshwater prawn in Thailand.
III. Surveillance, Monitoring and Diagnosis of Diseases of Aquatic Animals
III-1. Responsible Facility and Personnel
Two main research institutes, the Inland Aquatic Animal Health Research
Institute (AAHRI) and the Coastal Aquatic Animal Health Research Institute,
are designated as Central Laboratories of the DOF. The DOF also has another
11 PCR-capable laboratories that are based in 11 Coastal Fishery Research
and Development Centers. These two main research institutes and 11 PCR
laboratories are responsible for diagnosis and inspection services. Below is
the complete contact information for the two main institutes:
Fishery Biologists conduct diagnosis and inspection services under
supervision of the Directors of Inland and Coastal Aquatic Animal Health
Research Institutes, and the Directors of 11 Coastal Fishery Research and
Development Centers where PCR laboratories are located. Surveillance and
monitoring for diseases of aquatic animals are conducted regularly.
III-2. Diagnostic Capabilities and Major Diseases of Aquatic Animals
Laboratories of the DOF have capabilities for Level II and III diagnosis. University-based laboratories can also diagnose diseases at Levels II and III. Specifically, they are based at the following universities:
Many private laboratories and shrimp farms have PCR laboratory to detect viral diseases in shrimp. Feed manufacturers and dealers also offer PCR diagnostic services to shrimp farmers.
Table 3. List of economically important diseases of aquatic animals
IV. Quarantine Services to Prevent Entry of Diseases of Aquatic Animals
IV-1. Responsible Facility, Agency and Personnel
The DOF is responsible for quarantine of aquatic animals. When live aquatic animals arrive in the country, they will be are quarantined at the importing company's facilities that passed the quarantine standard. A Fish Health Inspector will inspect the animals at the quarantine zone. Fish samples will be taken and sent to the laboratory for pathogen detection. The Fish Quarantine Inspector conducts quarantine and inspection services at the port of entry, while a Fish Health Inspector conducts inspection at the quarantine zone of the importing company. The Fish Health Inspectors are Fishery Biologists or Fish Pathologists working at the Inland or Coastal Aquatic Animal Health Research Institutes, and the Coastal Fishery Research and Development Centers. Level III diagnosis is used on fish for shipment at the quarantine zone of the importing premises.
IV-2. Procedures and Requirements for Importation
Steps for live aquatic animal importation into Thailand:
IV-3. List of Quarantinable Diseases of Aquatic Animals
a. Viral diseases: Epizootic haematopoietic necrosis, Spring viraemia of carp, Viral encephalopathy and retinopathy, Grouper iridoviral disease, koi herpesvirus, Taura syndrome, White spot disease, Yellowhead disease, and Infectious hypodermal and haematopoietic necrosis virus
b. Bacterial diseases: none
c. Fungal diseases: none
d. Parasitic diseases: none
Requirements for Importation of Aquatic Animals into Thailand for Culture Purpose
The Department of Fisheries (DOF) has set up a new regulation to prevent and control aquatic animal diseases through importation. The imported aquatic animals are subject to quarantine at the approved quarantine zone of the importing companies for at least of 15 days. Health inspectors will inspect the animals in the quarantine zone and will take samples for laboratory tests. A health certificate must be presented at the port of entry together with the aquatic animal shipment. The health certificate must be issued by competent authority, signed by veterinarian or authorized officer, and must contain information as follows;
V. Research and Training of Fish Health Staff for Quarantine,Diagnosis, and Surveillance of Diseases of Aquatic Animals
AAHRI has trained 2 groups of DOF staff on topics related to surveillance,
monitoring and diagnosis of fish diseases. Group one was composed of
Fishery Biologists based at the Fisheries Research and Development Centers
and they received Level II training course program. Group two was composed
of Provincial Fishery Officers based at the Provincial Offices and they
received Level I training course program.
References
Fishery Statistics Analysis and Research Group 2001. Freshwater
Fish farm
Production 2001. Fishery Information Technology Center, Technical
Paper No. 10/2003, Department of Fisheries, Bangkok. 65 p.
Hastein, T. 2000. Principles of prevention and control of aquatic animal diseases. 68th General Session of the International Committee, May 22-26, 2000, Paris. Office International Des Epizooties, Paris. 31 p.
Current Status of Transboundary Fish Diseases in
Vietnam: Occurrence, Surveillance, Research and
Training
Kim Van Van
Research Institute for Aquaculture No. 1
Dinh Bang, Tu Son, Bac Ninh
Vietnam
I. Current Status of Koi Herpesvirus Disease (KHVD) in the Production of Common Carp and Koi
I-1. Production of Common Carp and Koi
a. Production of Common Carp
Common carp is a fish species which can be found in natural water
bodies like rivers (Red, Gam, Day, Duong rivers) and lakes (Thac Ba, Hoa
Binh, Nui Coc lakes). The production of common carp harvested in wild
habitats is declining due to over harvesting and use of destructive methods
like electric shock. However, data of wild common carp harvest are
unavailable.
Common carp is usually cultured in polyculture system with other carps
such as grass carp, Indian carp (Rohu and Mrigal), silver carp and black
carp in ponds, rice fields, or reservoirs using extensive or semi-intensive
methods. By these culture methods, common carp can grow to 800-1500
grams in the first year. We have no information about annual production of
common carp.
Most broodstocks belong to government hatcheries and some of them
belong to private hatcheries, but common carp fingerling production is usually
done by private farms. Recently, cultured common carp is classified as a
hybrid between Hungary cross Indonesia with Vietnamese common carp.
Presently, Vietnam hybrid common carp is exported to Lao PDR, Thailand,
India and Bangladesh.
b. Production of Koi
Information about koi culture in Vietnam is not available.
I-2. Koi Herpesvirus Disease (KHVD) of Common Carp and Koi
There is no information about KHVD of common carp and koi in Vietnam.
II. Current Status of Viral Diseases and in the Production of Shrimps and Prawn
II-1. Production of Shrimps
a. Production of Tiger Shrimp (Penaeus monodon)
Tiger shrimp is cultured in brackishwater farms all over country using 3 methods: extensive, semi-intensive, and intensive systems. Depending on the culture method, production ranges from 200 kg in extensive system to 6000 kg (sometimes up to 12 tons/ha/cycle) in intensive system per cycle. Different areas have different cycles. In northern Vietnam (from Hue up to Quang Ninh) there is often only one cycle that starts culture in April and harvests in August. In central and southern Vietnam, there can be more than one cycle. In 2001, the whole country had 230,000 ha for P. monodon culture with total production of 155,000 metric tons (MT). In 2003, the shrimp culture area increased to 575,137 ha (with 476,528 ha in southern provinces; 16,499 ha in central provinces; and 39,142 ha in northern provinces) producing more than 200,000 MT. Of this, 15,534 ha was for intensive culture (2.84%), 20,116 ha for semi-intensive culture (3.67%), and the remaining area for extensive and improved extensive culture. Spawners and broodstocks are caught by fishing vessels from coastal areas in Vietnam, but some of them are imported from Thailand, Indonesia, Taiwan, China and Singapore. Postlarvae are produced mainly by private hatcheries located in central and southern Vietnam. In 2002, Vietnam produced 18 billion postlarvae from more than 4,000 hatcheries. In 2003, the number of hatcheries increased to 5,017 of which 1,282 are in Khanh Hoa, 1,200 in Ninh Thuan, 850 in Ca Mau, and 253 in Ba Ria Vung Tau and other places. These hatcheries produced 25.17 billion postlarvae. There is no information on importation record of various stages of P. monodon. Most live export records are of marketable shrimp and some live stock records are stocked to Cambodia. In 2003, Vietnam exported 500,000 MT of shrimps to the United States, an increase of 17.5% compared with 2002 record.
b. Production of Pacific White Shrimp (Litopenaeus vannamei)
Vietnam started importing this species in 2002 through Asia Hawaii Ventures Ltd. This company has cultured Pacific white shrimp at very high density and produced 17 tons/ha/cycle that runs only for 3 months. At present, this species is cultured in both freshwater and brackishwater ponds. Initially, postlarvae were imported from China and Taiwan. Afterwards, broodstocks and spawners were brought into Vietnam. Presently, broodstock is cultured and matures in ponds in Vietnam.
c. Production of Freshwater Prawn (Macrobrachium rosenbergii)
In 1997, the Ministry of Fisheries imported M. rosenbergii from China
for prawn culture in northern Vietnam. In that region, prawn is stocked in
April and harvested in November. For monoculture system, production is 1-
1.2 tons/ha/cycle in semi-intensive system, and 1.7-3.0 tons/ha/cycle in
intensive system. In polyculture system with carp and tilapia, the production
is 0.6-0.8 tons of prawn/ha/cycle. Prawn is cultured in both ponds and rice
fields. The stocking density is 15 individuals/m2 with one cycle lasting for 5
months.In 2000, there were only 4 hatcheries in northern Vietnam that produced
22 million postlarvae. In 2003, the whole country had 70 hatcheries producing
92 million postlarvae. Of these postlarvae, 40 million came from Can Tho,
14 million from An Giang, 15 million from Hai Phong, and 7 million from
Ninh Binh. Some postlarvae of M. rosenbergii were imported from China.
II-2. White Spot Syndrome Virus (WSSV)
a. In the last five years, outbreaks of WSSV often occurred in many places affecting all stages of shrimp. Species of shrimp that were infected were Penaeus monodon, P. indicus, P. japonicus, P. merguiensis and L. vannamei. Shrimps usually got infected at 40 days of culture after attaining 2.5 g/individual. Mortality rates in affected stocks reached up to 100% within 3-10 days.
b. Clinical signs of WSSV-affected shrimp include swimming on the water surface and staying near the dike. Feeding is reduced and shrimp show empty intestine. White spots appear in the carapace with sizes ranging from 0.5-2 mm. Some affected shrimp have pink to reddish discoloration.
c. Most often, diagnosis is based on clinical signs, but histopathology and PCR are also used.
d. Economic losses due to WSSV: In some cases, losses of up to 100% were recorded, but there are no estimates on their monetary equivalent.
e. Importation record and country of origin is mentioned in section II- 1b.
II-3. Taura Syndrome Virus (TSV)
Little information about dates and locations of outbreaks of TSV is available in Vietnam. In May 2004, the laboratory of the Research Institute for Aquaculture No. 1 inspected three positive samples of postlarvae of L. vannamei. Diagnosis was based on clinical signs, histopathology and PCR analysis.
II-4. Significant and Emerging Viral Diseases of Macrobrachium rosenbergii
There is no information on viral diseases affecting M. rosenbergii.
III. Surveillance, Monitoring and Diagnosis of Diseases of Aquatic Animals
III-1. Responsible Facility and Personnel
a. The Responsible Facilities and Their Locations
b. The Contact Persons in These Laboratories
1. Mrs. Phan Thi Van (RIA1)
2. Mrs. Ly Thi Thanh Loan (RIA2)
3. Mr. Vo Van Nha (RIA3)
4. Dr. Do Thi Hoa, Nha Trang Fisheries University
5. Nguyen Tu Cuong NAAFIQAVED
c. Surveillance and Monitoring
These activities are done by RIA 1, 2 and 3.
III-2. Diagnostic Capabilities and Major Diseases of Aquatic Animals
Based on the agreed-upon levels of diagnosis, the capability of the laboratories is upper Level II, but under Level III because Level II plus PCR method are employed. Virology work and cell line culture is just starting.
a. Definition of Levels of Diagnosis
Level I: Diagnostic activity limited to observation of animal and the environment, and clinical examination (On Site or Field Diagnosis).
Level II: Diagnostic activity includes Parasitology, Bacteriology, Mycology, and Histopathology (Laboratory Diagnosis).
Level III: Diagnostic activity includes Virology, Electron microscopy, Molecular biology and Immunology (Laboratory Diagnosis).
c. List of Economically-Important Diseases of Aquatic Animals
IV. Quarantine Services to Prevent Entry of Diseases of Aquatic Animals
IV-1. Responsible Facility Agency and Personnel
a. Responsible Facility
The National Fisheries Quality Assurance and Veterinary Directorate (NAFIQAVED) is responsible for quarantine of aquatic animals. When live
aquatic animals arrive in the country, RIA1, 2 and 3 are conduct quarantine
and inspection service.
b. Responsible Persons
Nguyen Tu Cuong
General Director,
NAFIQAVED
10B Nguyen Cong Hoan - Ba Dinh district - Hanoi City
Nguyen Nhu Tiep
Head of Aquatic Veterinary Department
NAFIQAVED
10B Nguyen