Judul: Aplikasi probiotik, prebiotik, dan sinbiotik melalui pakan pada udang vaname Litopenaeus vannamei yang diinfeksi bakteri Vibrio harveyi
Abstrak: Luminous vibriosis caused by Vibrio harveyi were commonly treated with antibiotic, but recently the use of antibiotics is restricted because it induces antibiotic-resistant bacteria and leave residue in shrimp’s body. An alternative solution that can be done to treated luminous vibriosis is by using applications of probiotic, prebiotic, and synbiotic. The aim of this research was to examine the effect of probiotic, prebiotic, and synbiotic on the survival rate and growth of pacific white shrimp against V. harveyi infection. Feed as treatment was supplemented with probiotic 1%, prebiotic 2%, and probiotik 1% + prebiotic 2% (synbiotic). Shrimps feed without supplementation of probiotic and prebiotic was used as control treatment. Shrimp test inserted into the aquarium (60x30x35) cm as much as 15 pic with a density of 40 shrimps/ 40 liters/ aquarium and an average weight of 0.4 ± 0.1 grams. After 30 days of feeding treatment, the shrimp was challenged by immersion with V. harveyi solution containing 106 CFU/ml. Survival rate of shrimp was measured before and after challenge while growth and feed convertion were observed before challenge test. Research result showed that growth (5.89%), feed convertion (1.21), and survival rate (80%) before challenge of shrimp fed diet supplemented with synbiotic were better then shrimp fed diet supplemented with probiotic and prebiotic. After challenge, survival rate (83.33%) of shrimp fed diet supplemented with synbiotic was better then prebiotic (51.67%) and positive control (31.67%).
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Judul: Application of probiotic, prebiotic and synbiotic to enchance the immune response of shrimp Litopenaeus vannamei against Vibrio harveyi infection
Abstrak: Probiotic, prebiotic and synbiotic are now widely used in aquaculture and showed their capability in controlling the bacterial disease. The aim of this study was to the test the effectiveness of probiotic, prebiotic and synbiotic in enhancing the immune response of shrimp againts Vibrio harveyi infection. This research comprised of 5 treatments, namely: control P0(+), control P0(-), 1% probiotic (P1), 2% prebiotic (P2) and synbiotic (1% probiotic+2% prebiotic: P3). Probiotic SKT-b (dose 106 CFU/ml) was supplemented into bacterial feed. Prebiotic used in this study was oligosaccharides derived from sweet potato varietie of Sukuh (2% of the feed weight). Shrimp used in this study was Litopenaeus vannamei larvae (±3.5 g in weight). Shrimp were cultured aquaria 60x35x30 cm3 filled with 40 L seawater for 28 days. Immune response parameters observed including total hemocyte, phagocytic activity and phenoloxidase activity (PO). Each parameter was observed 9 times, i.e at 0, 7 and 14 day of culture and after a challenge test, i.e at the 6, 12, 24, 72, 120 and 168 hours post infection. Post-test results showed that the highest survival P3 treatment (100%), followed by P1(90%), P2(83%), and P0(+)(60%) showed by respectively. The results of the immune response observed during the study showed the highest in P3 (total hemocyte 3,36±0,05- 9,32±0,05x106 cells/ml, phagocytic activity of 16,48±0,14-77,55±0,22% and PO activity 0,128±0,03-0,591±0,01) and the lowest was P0(+) (total hemocyte 3,15±0,16-4,53±0,33x106 cell/ml; phagocytic activity 10,15±0,10-20,78±0,34% and PO activity 0,128±0,03-0,181±0,03). From this study, we concluded that the addition synbiotic into the feed can improve the immune response of shrimp better than the other treatments.
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Judul: Closed Knight’s Tour pada Papan Catur Berbentuk Persegi Panjang dengan Ukuran Maksimal 8 × 8
Abstrak: Closed Knight’s Tour merupakan langkah kuda yang mengunjungi setiap kotak pada papan catur tepat satu kali dengan langkah kuda berawal dan berakhir pada kotak yang sama. Graf yang terbentuk dari closed knight’s tour dinotasikan sebagai graf G(m,n), dengan m adalah banyaknya baris dan n adalah banyaknya kolom. Graf tersebut memuat Hamiltonian cycle. Sebuah graf terhubung G adalah graf bipartite jika dan hanya jika graf tersebut tidak memiliki cycle dengan panjang ganjil. Papan catur yang memenuhi syarat cukup untuk memiliki closed knight’s tour adalah papan catur berukuran 5 × 6, 5 × 8, 6 × 6, 6 × 7, 6 × 8, 7 × 8, dan 8 × 8.
Keyword: bipartite, closed knight’s tour, hamiltonian cycle, knight’s tour, teori graf