Judul: Experimental Models of Vibrio parahaemolyticus Infection in White Leg Shrimp Litopenaeus vannamei
Abstrak: Penyakit Vibriosis disebabkan oleh bakteri genus Vibrio. Penyebaran penyakit pada organisme budidaya dapat terjadi secara horizontal maupun vertikal. Penyebaran penyakit secara vertikal terjadi karena perpindahan dari induk ke benur, sedangkan penyebaran secara horizontal terjadi akibat penyebaran dari satu udang ke udang lain. Penelitian ini bertujuan mengevaluasi dampak transmisi penyakit AHPND secara horizontal melalui media pemeliharaan dan kanibalisme. Penelitian dilakukan menggunakan rancangan acak lengkap (RAL) yang terdiri dari tiga perlakuan serta tiga kali ulangan. Pada perlakuan kanibalisme (Kan), udang sehat diberi pakan udang mati yang terkonfirmasi membawa V. parahaemolyticus. Pada perlakuan kohabitasi (Koh), udang diinfeksi V. parahaemolyticus dengan metode injeksi dan dipelihara bersama udang sehat dengan pembatas berupa hapa, serta pada perlakuan kontrol, udang diberi pakan komersial. Parameter yang diuji yaitu kematian kumulatif, gejala klinis, identifikasi bakteri Vibrio sp., konfirmasi AHPND menggunakan metode PCR, dan histopatologi. Kematian kumulatif hingga akhir pemeliharaan mencapai 83,33±20,82% pada penularan melalui kanibalisme dan 6,67±11,55% melalui kohabitasi. Gejala infeksi V. parahaemolyticus ditemukan dengan kondisi hepatopankreas yang berwarna pucat. Udang pada perlakuan yang terkonfirmasi positif V. parahaemolyticus strain AHPND dengan kepemilikan gen toksin PirA dan PirB dengan terbentuknya pita DNA yang teramplifikasi pada 230 bp. Histopatologi yang terlihat pada udang yang terinfeksi V. parahaemolyticus strain AHPND adalah terjadinya pengelupasan sel epitel tubulus hepatopankreas secara massif yang dimulai dari pusat hepatopankreas dan berlanjut ke luar ke daerah embrionik. Penyakit yang disebabkan oleh V. parahaemolyticus lebih mudah ditransmisikan melalui kanibalisme dibanding dengan melalui kohabitasi atau hidup bersama., Vibriosis is caused by bacteria of the genus Vibrio. Disease spread in aquaculture organisms can occur horizontally or vertically. Vertical spread of the disease occurs due to transfer from broodstock to fry, while horizontal spread occurs due to spread from one shrimp to another. This study aims to evaluate the impact of horizontal transmission of AHPND disease through rearing media and cannibalism. The study was conducted using a completely randomized design (CRD) consisting of three treatments and three replications. In the cannibalism treatment (Kan), healthy shrimp were fed dead shrimp confirmed to carry V. parahaemolyticus. In the cohabitation treatment (Koh), shrimp were infected with V. parahaemolyticus by injection method and kept with healthy shrimp with a barrier in the form of a hapa, and in the control treatment, shrimp were fed commercial feed. The parameters tested were cumulative mortality, clinical symptoms, identification of Vibrio sp. bacteria, confirmation of AHPND using the PCR method, and histopathology. Cumulative mortality until the end of rearing reached 83.33 ± 20.82% in transmission through cannibalism and 6.67 ± 11.55% through cohabitation. Symptoms of V. parahaemolyticus infection were found with pale hepatopancreas. Shrimp in the treatment were confirmed positive for V. parahaemolyticus strain AHPND with the possession of PirA and PirB toxin genes with the formation of a DNA band amplified at 230 bp. Histopathology seen in shrimp infected with V. parahaemolyticus strain AHPND is a massive exfoliation of hepatopancreatic tubular epithelial cells starting from the center of the hepatopancreas and continuing outward to the embryonic region. The disease caused by V. parahaemolyticus is more easily transmitted through cannibalism than through cohabitation.
Keyword: cannibalism, cohabitation, experimental models, Vibrio parahaemolyticus, white leg shrimp

Judul: Distribusi Vibrio parahaemolyticus dari Awal Masa Infeksi sampai Terjadi Kematian pada Udang Vaname Litopenaeus vannamei
Abstrak: Vibrio parahaemolyticus merupakan bakteri halofilik gram negatif yang secara umum ditemukan pada perairan tropis dan juga di lingkungan budidaya. Kegiatan budidaya dapat terhambat oleh adanya infeksi V. parahaemolyticus yang menjadi agen utama penyebaran penyakit Acute Hepatopancreatic Necrosis Disease (AHPND) dengan dihasilkannya toksin pirA dan pirB. Penelitian ini bertujuan menginvestigasi penyebaran bakteri V. parahaemolyticus pada organ udang berdasarkan variasi waktu pasca pemaparan bakteri. Penelitian dilakukan menggunakan rancangan acak lengkap (RAL) yang terdiri dari dua perlakuan serta tiga kali ulangan. Perlakuan pertama yaitu pemeliharaan dengan penambahan bakteri uji V. parahaeomlyticusRf 106 CFU/mL dan pemeliharaan tanpa penambahan bakteri uji pada perlakuan kedua. Parameter yang diuji yaitu gejala klinis, kelangsungan hidup, total perhitungan bakteri uji pada organ insang, usus dan hepatopankreas, respons imun yang terdiri dari phenol oxidase activity (PO) dan respiratory burst (RB), histopatologi, serta konfirmasi PCR. Tingkat kelangsungan hidup selama 7 hari pasca infeksi mencapai 64,4±13,7%. Gejala klinis pada udang yang terinfeksi dapat diamati secara visual melalui organ hepatopankreas dan usus yang berwarna pucat. Populasi bakteri pada seluruh organ insang, usus dan hepatopankreas selama masa pengujian melebihi batas minimal yang dapat ditolerir udang (103 CFU/g) dengan populasi terbanyak berada di organ usus, insang, dan paling sedikit ditemukan pada hepatopankreas. Histopatologi pada udang yang terinfeksi dapat diamati dengan adanya kerusakan organ yang terjadi diantaranya deformasi sel tubular pada hepatopankreas serta disintegrasi sel epitel usus. Respons imun (RB dan PO) lebih tinggi pada udang yang diinfeksi dibandingkan dengan udang tanpa diberi perlakuan. Udang pada perlakuan penambahan bakteri positif terinfeksi oleh bakteri uji dengan terbentuknya pita DNA yang teramplifikasi pada 230 bp., Vibrio parahaemolyticus is a gram-negative halophilic bacterium generally found in tropical waters and cultivation environments. Cultivation activities can be hampered by infection with V. parahaemolyticus the main agent for the spread of Acute Hepatopancreatic Necrosis Disease (AHPND) by producing pirA and pirB toxins. This study aims to investigate the spread of V. parahaemolyticus bacteria in shrimp organs based on variations in time after exposure to the bacteria. The research used a completely randomized design (CRD) consisting of two treatments and three replications. The first treatment was maintenance by adding the test bacteria V. parahaeomlyticusRf 106 CFU/mL and maintenance without adding test bacteria in the second treatment. The parameters tested were clinical symptoms, survival rate, the total count of test bacteria in the gills, intestines and hepatopancreas, immune response consisting of phenoloxidase activity (PO) and respiratory burst (RB), histopathology, and PCR confirmation. The survival rate for 7 days after infection reached 64,4±13,7%. Clinical symptoms in infected shrimp can be observed visually through the pale-colored hepatopancreas and intestines. The bacterial population in all gills, intestines and hepatopancreas during the testing period exceeded the minimum tolerable limit for shrimp (103 CFU g -1 ) with the largest population being in the intestines, gills, and the least found in the hepatopancreas. Histopathology in infected shrimp can be observed by organ damage, including deformation of tubular cells in the hepatopancreas and disintegration of intestinal epithelial cells. The immune response (RB and PO) was higher in infected shrimp than in untreated shrimp. Shrimp in the treatment with the addition of positive
Keyword: distribution, immersion, vaname shrimp, Vibrio parahaemolyticus

Judul: Pembuatan Film Tipis Cu2ZnSnS4 sebagai Lapisan Penyerap Cahaya pada Sel Surya Menggunakan Metode Elektrodeposisi
Abstrak: Thin film of Cu2ZnSnS4 (CZTS) is an alternative semiconductor used as light absorber layer on solar cell. CZTS can replace silicon that commonly used as commercial semiconductor. The advantage of using CZTS as absorber layer is due to the abundance of its chemical composer on earth, and its high value of absorption coefficient. The absorber layer was made by using electrodeposition method on ITO glass substrates. The films were deposited at room temperature using potentiostatic mode with a potential of –1.05 V for 30, 45, and 60 minutes. After that, the films were annealed at two different temperatures, 180 ºC and 500 °C, for 45 minutes in N2/H2S atmosphere. Based on X-ray diffraction analysis, the polycrystalline thin film obtained fall into kesterite crystal phase. This type of crystal was obtained when the CZTS was annealed at 500 °C in H2S/N2 atmosphere. The value of optical band gap energy for the CZTS thin film was 2.2 eV with the film thickness about 1.228–6.366 μm. The sample of CZTS with electrodeposition time of 45 minutes and annealing temperature of 500 °C showed the best result and in conformity with absorber layers criteria for solar cells.
Keyword: semiconductor, ITO glass, CZTS thin film, electrodeposition