KAJIAN EPIDEMIOLOGI WHITE SPOT SYNDROME VIRUS (WSSV) PADA TAMBAK TRADISIONAL UDANG WINDU (Penaeus monodon Fab.) DI KABUPATEN DEMAK

TASLIHAN, Arief , Bambang Sumiarto

2014 | Tesis |

Penyakit bercak putih viral yang disebabkan oleh WSSV menjadi kendala utama di tambak udang, terutama tambak udang windu tradisional di Indonesia. Terkait dengan aspek pengendalian penyakit yang disebabkan oleh WSSV telah dilakukan penelitian untuk mengetahui prevalensi WSSV pada tambak tradisional udang windu di wilayah kabupaten Demak, uji transmisi WSSV, dan Uji pengendalian penularan WSSV dengan penerapan BMP klaster dan tambak penyanggah. Metode yang diterapkan adalah lintas seksional, dengan pengambilan sampel sebanyak 90 tambak yang mewakili kawasan tambak yang termasuk kategori aktif berproduksi. Transmisi WSSV serta kemungkinan trisipan sebagai karier bagi WSSV dilakukan melalui uji kohabitasi dan ingesti secara laboratorium. Penelitian ini juga menentukan waktu konsentrasi lethal yang mengakibatkan kematian 50% populasi udang. Pengujian teknik budidaya untuk mengetahui efektifitas mengendalian transmisi WSSV di tambak tradisional dilakukan pada tambak udang windu tradisional dengan model klaster dan dikelilingi tambak buffer berupa tambak berisi non-udang. Hasil penelitian menunjukkan bahwa prevalensi tambak terserang WSSV adalah antara 65,6% (CI=55,7% - 75,4%). Faktor yang mempengaruhi kejadian WSSV adalah pemilihan benih (Koefesien=1,517; P < 0,049; Odd ratio (OR)=4,56), luas tambak (Koefisisen=0,0002; P<0,0089; OR=2,718) dan pengeringan tambak (Koefisien=-3,756;P<0,001; OR=0,02). Faktor yang secara langsung berpengaruh terhadap kejadian infeksi WSSV adalah aklimasi benih dan luasan tambak, sedangkan yang secara langsung tetapi dapat menekan kejadian infeksi WSSV adalah pengeringan tambak. Faktor yang tidak langsung berpengaruh terhadap infeksi WSSV adalah penyaringan air, stadia benih dan seleksi benih. Beberapa faktor yang mempengaruhi produksi udang di tambak secara berurutan adalah penyaringan air sebelum masuk ke dalam tambak (koefisien=0,88651; P=0,0110), lokasi tambak terhadap laut (koefisien=0,79665; P=0,0162), stadia benih Pl-40 (koefisien=0,65254; P=0,0091), pengeringan tambak sebelum penebaran benih (koefisien= 0,44606; P=0,0584), dan sintasan udang (koefisien=0,1141; P=0,0024). Strain WSSV di wilayah Sidorejo adalah TRS 10 dan 14, sedangkan di Tambakpolo TRS 5. Uji transmisi WSSV didapatkan bahwa WSSV dapat menular secara kohabitasi dari udang windu ke udang windu maupun udang windu ke udang vannamei. Konsentrasi WSSV hingga 2,75 x 104 kopi/L menyebabkan kematian dan infeksi terhadap udang windu sehat dengan nilai LT-50 2,75 x 105 kopi WSSV/L selama 108 jam. Penularan penyakit yang disebabkan oleh WSSV dapat dicegah melalui penerapan klasterisasi tambak udang windu yang dikelilingi dengan tambak berisi non-udang. Dapat disimpulkan bahwa wabah WSSV termasuk hiperendemik di tambak tradisional yang infeksinya dipengaruhi oleh pemilihan benih, tambak terlalu luas dan pengeringan tambak, dan transmisinya melalui air. Pengendalian WSSV dapat secara efektif melalui penerapan klaster dengan tambak penyanggah berisi ikan.

White spot viral disease caused by White Spot Syndrome Virus (WSSV) was a major constraint in shrimp farms, particularly traditional shrimp ponds in Indonesia. In relation to control the disease caused by WSSV, research has been done to find out The status of WSSV prevalence in traditional shrimp farms in the district of Demak, transmission trial of WSSV and implementation of model to control WSSV transmission through BMP cluster management. The method applied was crosssectional. As much as 90 ponds of traditional pond which were actively growing shrimp randomly selected as samples. Study on WSSV transmission through different mechanism and career were carried out through water, cohabitation and ingestion trial at laboratory scale. This study was also determined a lethal time at 50% of different WSSV concentration on shrimp population. Control of WSSV transmission in tradional shrimp pond was also conducted by implementing BMP in cluster system. Shrimp ponds put into clustered surrounded by ponds growing only fish instead of shrimp. Results of the study found that WSSV prevalence in shrimp farms was 65,6%, (CI=55.7% - 75.4%). Factors affecting prevalence were seed selection (Coeffisien=1.517; P < 0.049; Odd ratio (OR=4.56), pond size (Coeffisien=0.0002; P<0.0089; OR=2.718) and pond drying prior to stock fry (Coeffisien= -3.756; P<0.001; OR=0.02 ) consecutively. Path analysis on risk factors revealed that factors directly affected on WSSV infection were seed acclimation and pond size, while factor that prevented WSSV infection was pond drying. Factors affected on WSSV infection indirectly were screening water, seed stadia, and seed selection. Factors influenced on shrimp production were screening water prior to entered the pond (coeffisien=0,88651; P=0,0110), pond location related to sea coast (coeffisien=0,79665; P=0,0162), seed stadia of Pl-40 (coeffisien=0,65254; P=0,0091), pond drying during pond preparation (coeffisien= 0,44606; P=0,0584), survival rate (coeffisien=0,1141; P=0,0024). Genetic analysis base on TRS revealed that WSSV strains infected shrimp in the Sidorejo area were TRS 10 and 14, while in Tambakpolo was TRS 5. Results of study found that WSSV transmission could be through cohabitation from WSSV infected shrimp to healthy shrimp. White spot syndrome virus concentration up to 2.75 x 104 copy/L can affected infection and death to healthy shrimp with LT-50 WSSV for shrimp coffee at 2.75 x 105 /L for 108 hours. Result of study proven that brackishwater snail was not a career for WSSV. Implementation of BMP-based clustering shrimp pond surrounded by buffer ponds proven effectively prevented transmission of disease caused by WSSV originated from surrounding area. It can be concluded that the WSSV prevalence in traditional tiger shrimp was considered hyperendemic. Risk factor related to infection were seed selection, pond size and drying ponds. Transmission of WSSV mainly through water and cohabitation. Implementation BMP cluster system surrounded by pond growing only finfish effectively controled WSSV transmission from WSSV outbreak in local area.

Kata Kunci : White spots disease virus, tiger shrimp, extensive shrimp pond, BMP