Judul: Immune system and production of pacific white leg shrimp on the different stocking density and sediment redox potential
Abstrak: Pacific white leg shrimp is a desirable species for shrimp farmers, which has eral advantages such as the availability of specific pathogen free post larvae, i relatively fast growth, and high survival rate. Pacific white leg shrimp Li 'P,enaeus vannamei has become one of the most important species in aquaculture sectors, including in Indonesia. Indonesian shrimp production had en dramatically increased during the last decade, from 191 148 MT in 2003 to 593 280 MT in 2014 or about 213% increase. The increase of shrimp production is ostly due to new openings of farming area and by intensification by increasing the stocking density. However, despite the progressive increase in production, shrimp-farming industry still encounters some major challenges among which is disease outbreak. Disease outbreak and environmental quality in shrimp culture systems are closely related. It has been suggested that viral and bacterial diseases, together with poor soil and water quality, were the main causes of the reported shrimp mass mortality in several studies. The aim of this study is to evaluate the effects of stocking density and sediment redox potential on the shrimp production performance and non-specific immune response. This study consisted of three main research stages with the following objectives: first, to observe the behavioural activity of L. vannamei and its oxygen consumption, as well as sediment oxygen demand in relation to sediment redox condition; second, to evaluate the effect of shrimp density on the animals immune system and growth performance, as well as the water quality in the culture system; and third, to evaluate the effects of sediment redox potential and shrimp stocking density on the sediment and water quality parameters, shrimp production performance, and immune response and resistance upon white spot syndiome virus (WSSV) challenge The first experiment was conducted in semi outdoor laboratory using 18 units of aquarium with a dimension of 30 cm x 30 cm x 100 cm. Each aquarium was filled with filtered seawater and 5 cm deep soil substrate with different redox pote tial at the bottom of each tank. Shrimp were randomly distributed into the tank at a stocking density of 130 shrimps m·²• One hour after being transferred to the aguarium, the shrimp swimming behaviour was observed for 6 consecutive hours, during which no feed was given to the shrimp. At the initial and end of expe ·ment, dissolved oxygen was measured at different depth. The study showed that sediment redox potential did not influence L. vannamei behavioural profile. Shrimp stayed on the tank bottom for most of the time in all treatments and these demonstrate that these animals were unable to stay for a long time in the water co , . Dissolved oxygen decreased with the increase of the water depth incHcating that dissolved oxygen on the bottom was consumed by both shrimp and s i; ent with the more negative sediment redox potential the higher sediment en demand. In the second experiment, a completely randomized experimental design was applied with four different stocking densities, i.e. 50, 150, 300 and 600 shr· s m·2 with four repetitions. Eighteen units of
Keyword: Stocking, White leg shrimp, Sediment redox

Judul: Effect of Organic Selenium on Production Performance  and Immune Response of White Leg Shrimp Infected with Vibrio parahaemolyticus
Abstrak: Udang vaname merupakan produk utama budidaya perikanan dan juga berisiko terserang penyakit AHPND (Acute Hepatopancreatic Necrosis Diseases) yang disebabkan oleh Vibrio parahaemolyticus. Salah satu alternatif untuk mencegah infeksi bakteri yaitu dengan menggunakan selenium organik. Tujuan penelitian ini untuk menganalisis pengaruh selenium organik dengan dosis berbeda melalui pakan terhadap kinerja produksi dan respons imun udang vaname yang diinfeksi V. parahaemolyticus. Udang yang digunakan memiliki bobot awal 5,64±0,18 g yang dipelihara selama 30 hari dan diuji tantang dengan V. parahaemolyticus dengan dosis 105 CFU/ekor pada hari ke-31 setelah diberikan pakan uji coba, kemudian mortalitas diamati selama tujuh hari. Perlakuan yang diberikan yaitu 2, 6, 12, 18 mg/kg pakan, dan kontrol tanpa selenium organik. Pemberian selenium organik mampu meningkatkan kinerja produksi dan respons imun udang terhadap infeksi V. parahaemolyticus. Dosis terbaik diperoleh pada 2 mg/kg pakan yang mampu meningkatkan laju pertumbuhan harian, laju pertumbuhan spesifik, rasio konversi pakan, dan melindungi udang terhadap infeksi V. parahaemolyticus., Pacific white leg shrimp is the main product of aquaculture and is also at risk of AHPND (Acute Hepatopancreatic Necrosis Diseases) caused by Vibrio parahaemolyticus. One alternative to prevent bacterial infection is to use organic selenium. The purpose of this study was to analyze the effect of organic selenium with different doses through feed on the production performance and immune response of shrimp infected with V. parahaemolyticus. The shrimp used had an initial weight of 5.64±0.18 g which was reared for 30 days and challenged by injection of V. parahaemolyticus at a dose of 105 CFU/shrimp on day 31st after given feed trials, then the mortality was monitored during seven days. The treatment given was 2, 6, 12, 18 mg/kg feed, respectively, and control without selenium organic. Administration of organic selenium was able to increase production performance and immune response of shrimp against V. parahaemolyticus infection. The best dose was obtained at 2 mg/kg feed which was able to increase the daily growth rate, specific growth rate, feed conversion ratio, and protect shrimp against V. parahaemolyticus infection.
Keyword: Bacteria, growth, immune, organic selenium, white leg shrimp

Judul: Cycle Hamilton pada Graf Lengkap, Graf Regular, dan Graf 2-Connected 4-Regular Berorder Kurang dari Sepuluh
Abstrak: Suatu graf disebut graf Hamilton apabila graf tersebut memuat cycle Hamilton, yaitu cycle yang melewati setiap vertex tepat satu kali. Menentukan keberadaan cycle Hamilton pada suatu graf dapat menggunakan syarat cukup yang berupa teorema-teorema yang telah diperkenalkan sejak tahun 1950-an. Beberapa syarat cukup yang dibahas dalam karya ilmiah ini adalah syarat cukup yang berhubungan dengan graf lengkap dan graf regular. Suatu graf lengkap berorder 𝑛������ ≥ 3 dan graf r-regular berorder 𝑛������ ≤ 2𝑟������ + 1 merupakan graf Hamilton, Karena kedua graf tersebut memuat cycle Hamilton. Selanjutnya, syarat cukup tersebut digunakan untuk menentukan keberadaan cycle Hamilton pada graf 2-connected 4- regular berorder kurang dari 10.
Keyword: graf Hamilton, graf regular, graf lengkap, graf 2-connected 4-regular