<p>The experiment was conducted to evaluate the presence of white spot syndrome virus (WSSV) and <em>Vibrio </em>sp. in clam, oyster crabs, squid and sea worm as fresh feed for tiger shrimp, <em>Penaeus monodon, </em>Broodstock. The presence of WSSV was detected by using polymerase chain reaction (PCR) method, while the <em>Vibrio </em>sp. was grown in TCBS agar and counted as cfu/g fresh feed. The result shows that all the feed have already infected by WSSV with light infection level. <em>Vibrio </em>sp. can be isolated from all samples and their population were 1.5 x 103 - 1,8 x 104 cfu/g fresh feed.</p> <p>Key words: WSSV, <em>Vibrio </em>sp., fresh feed, tiger shrimp broodstock</p> <p> </p> <p>ABSTRAK</p> <p>Penelitian ini dilakukan untuk mengetahui keberadaan <em>white spot syndrome virus </em>(WSSV) dan <em>Vibrio </em>sp. pada pakan segar untuk induk udang windu. <em>Penaeus monodon. </em>Pakan segar yang dievaluasi terdiri dari kerang, tiram, kepiting, cumi-cumi dan cacing laut. WSSV dideteksi dengan metode <em>polymerase chain reaction </em>(PCR). Kandungan <em>Vibrio </em>sp. dihitung dengan menginokulasikan 0,1 ml suspensi pakan segar pada agar TCBS. kemudian diinkubasikan pada suhu ruang selama 24 jam. Koloni bakteri yang tumbuh dihitung dan dinyatakan dalam cfu/g pakan. Hasil pengamatan menunjukkan bahwa semua jenis pakan segar terinfeksi WSSV pada skala ringan. <em>Vibrio </em>sp. dapat diisolasi dari semua jenis pakan segar, dan jumlah populasinya 1,5 x 103- 1,8 x 104 cfu/g pakan.</p> Kata kunci: WSSV, <em>Vibrio </em>sp., pakan segar, induk udang windu

The Vibrio group of bacteria is considered highly pathogenic to shrimp larvae. Shrimp larvae are susceptible to Vibrio. It is difficult to eradicate Vibrio from the hatchery environment completely. Efforts were made to design an effective disinfectant with almost no side effects or residues. A formulation was developed by combining essential oils with antimicrobial properties to fight against pathogenic Vibrios, such as Vibrio harveyi and V. parahaemolyticus, in a hatchery environment. The anti-Vibrio formulation is a blend of Eucalyptus globulus, jasmine, and gardenia oils, designated as essential oil blend formulation (EOBF). The effective dose of EOBF was optimized on bacteria using TSA and on Vibrio using TCBS agar media. The optimized dose of 40 ppm EOBF was sprayed on the tank and culture area dry surfaces. The trial sites selected were the water filter tank, maturation tank, fry reservoir tank, quarantine and maturation tank, hatchery tank, spawning tank, rinsing tank, plankton tank, larvae rearing tank, packing tank, artemia tank, polychaetes (bucket and floor), squid (equipment and table), and freshwater tank of an experimental hatchery. The swab samples were collected after 3 hours, and a significant decrease in Vibrio, mostly green colonies, such as Vibrio harveyi and V. parahaemolyticus, was found after EOBF application. The obtained results showed that EOBF is an effective disinfectant against pathogenic Vibrios in shrimp hatcheries.

Vibrio, mainly Vibrio harveyi, V. campbellii, V. parahaemolyticus and V. splendidus, especially in their luminescent form are considered highly pathogenic to shrimp larvae. An effort was made to minimize the luminescent Vibrio load using an essential oil blend formulation (EOBF) consisting of Eucalyptus oil, jasmine oil, and gardenia oil in equal proportions. An eighteen-day small hatcheryscale trial was initiated, starting from the nauplii stage. The shrimp were distributed into three groups and four replicates each: a negative control, positive control with four replicates, and an EOBF treatment group. The shrimp at the mysis stage were challenged using a sublethal dose of 10 3 CFU/mL luminescent Vibrio harveyi. The obtained results indicated that the presence of harmful Vibrio in tank water, was almost one log lower in the EOBF group than in the positive control. The presence of pathogenic luminescent Vibrio in the positive control was 45%, whereas it was 19% in the treatment group. In addition, the EOBF-treated had better performance, and productivity. The results of this trial suggest that EOBF can reduce pathogenic Vibrio in hatchery environments and can increase productivity.