YOGYAKARTA (KU) – Tiger Shrimp (Penaeus monodon fabr.) is one leading product of national marine and fisheries that is often cultivated. There are some other species of shrimp that have been developed and cultivated in Indonesia, such as fresh water shrimp, white shrimp, vanamei shrimp, and tiger shrimp. "The shrimp accepted in society is the tiger shrimp since its price is stable and its cultivation is widely known while the meat tastes delicious," said Head of Quarantine Agency in Juanda, Surabaya, Drs. Burhaidin, S.Pi., MP, in the open promotion of doctoral examination in Faculty of Veterinary Medicine, Universitas Gadjah Mada, on Tuesday (21/9).
The man born in Cirebon, West Java, on 10 December 1962 said that in the last ten years, the production of tiger shrimp nationally decreased to 70 thousand tons per year. This year the government’s target reached 699,000 tons, almost doubled from the previous year which was 348.1 thousand tons.
The decline of tiger shrimp production according to Nurhaidin is caused by shrimp disease, especially white spot syndrome virus (WSSV). Although seeding activity has been technically conducted in accordance with standard requirement, shrimp mortality caused by WSSV is still quite high, reaching 60-70 percent. "The virus that causes WSSV is an exotic virus that remains infectious despite in frozen condition. Transmission of the disease is from the species of imported shrimps that can occur if the virus can adapt to a new host," said the graduate of Master program in the Faculty.
Nurhaidin said that detection of WSSV infection should use sensitive and accurate methods in aquatic animal health management. Among the methods that have been developed by experts is DNA-based method, such as the polymerase chain reaction (PCR), which is considered most suitable for rapid detection and diagnosis of the viral disease on shrimps and mollusks. "Currently, DNA-based technology, particularly PCR has been widely applied in the field of aquaculture. Although it is very potent, but the use of DNA-based diagnostic technology routinely still causes some problems, because the high sensitivity causes the test unable to distinguish between living pathogen and the dead one and due to infection or contamination," he added.
Based on Nurhaidin’s research on 75 tiger shrimps from the tiger shrimp ponds in some districts in South Sulawesi, such as Maros, Pangkep, Pinrang, Barru, Takalar, Majene and Bonne, and Makassar, it is known that WSSV detection in black tiger shrimp using PCR method, is effective enough though level of sensitivity and specification is still relatively low. "The level of specifity and sensitivity are 72% and 66%," he explained. To overcome this, the knowledge on the factors that must be avoided is needed so that the PCR test that will be applied has a high diagnostic accuracy in terms of symptoms and clinical pathological lesions, the time of sampling, and human error.
Nurhaidin explained that WSSV infected shrimps showed symptoms of whitish spots with diameter of 1 cm on the surface on exoskeleton and the whole body of shrimp is pink to brownish red.