Judul: The Application of Probiotic Staphylococcus lentus L1k on Production Performance and Immune Response of Catfish (Clarias sp.) Infected with Aeromonas hydrophila
Abstrak: Produksi ikan lele yang terus meningkat memerlukan pengembangan budidaya dengan sistem intensif, namun penyebaran penyakit Motile Aeromonas Septicemia yang disebabkan oleh bakteri Aeromonas hydrophila dalam budidaya intensif masih menjadi masalah. Pencegahan penyakitnya dapat dilakukan dengan meningkatkan respons imun ikan melalui pemberian probiotik. Penelitian ini bertujuan menguji pengaruh aplikasi probiotik Staphylococcus lentus L1k dengan dosis yang berbeda terhadap kinerja produksi dan respons imun ikan lele (Clarias sp.) yang diinfeksi Aeromonas hydrophila pada dosis yang efektif. Penelitian terdiri atas lima perlakuan yaitu K+ (tanpa pemberian probiotik dan diuji tantang), K- (tanpa pemberian probiotik dan tanpa uji tantang), A (L1k 104 CFU mL-1 1% dan diuji tantang) B (L1k 106 CFU mL-1 1% dan diuji tantang), dan C (L1k 108 CFU mL-1 1% dan diuji tantang). Ikan uji memiliki bobot awal (29,49 ± 0,04) g dipelihara selama 30 hari dan diberi pakan suplementasi, kemudian diuji tantang dengan bakteri A. hydrophila selama 10 hari. Hasil penelitian menunjukkan pemberian probiotik Staphylococcus lentus L1k mampu meningkatkan kinerja produksi dan respons imun ikan lele (Clarias sp.) yang diinfeksi bakteri Aeromonas hydrophila dengan dosis terbaik pada pakan dengan penambahan bakteri Staphylococcus lentus L1k dengan dosis 104 CFU mL-1., The continuously increasing production of catfish requires the development of intensive aquaculture systems. However, the spread of Motile Aeromonas Septicemia disease caused by the bacterium Aeromonas hydrophila in intensive aquaculture remains a problem. Disease prevention can be achieved by enhancing the fish's immune response through the administration of probiotics. This study aims to test the effect of the application of Staphylococcus lentus L1k probiotics at different doses on the production performance and immune response of catfish (Clarias sp.) infected with Aeromonas hydrophila at an effective dose. The study consists of five treatments: K+ (no probiotic administration and challenged), K- (no probiotic administration and not challenged), A (L1k 104 CFU mL-1 1% and challenged), B (L1k 106 CFU mL-1 1% and challenged), and C (L1k 108 CFU mL-1 1% and challenged). The test fish had an initial weight of (29.49 ± 0.04) g and were reared for 30 days with supplemental feed, then challenged with A. hydrophila bacteria for 10 days. The results of the study show that the administration of Staphylococcus lentus L1k probiotics can improve the production performance and immune response of catfish (Clarias sp.) infected with Aeromonas hydrophila, with the best dose being 104 CFU mL-1 when added to the feed.
Keyword: Aeromonas hydrophila, catfish, Motile Aeromonas Septicemia, Staphylococcus lentus L1k

Judul: Application of Monospecies Synbiotic and Multispecies for Prevention of Aeromonas hydrophila Bacterial Infection in Sangkuriang Catfish (Clarias gariepinus)
Abstrak: Penyakit bakterial yang mengancam peningkatan produksi ikan lele salah satunya disebabkan oleh bakteri Aeromonas hydrophila. Penggunaan sinbiotik yang merupakan kombinasi probiotik dan prebiotik menjadi alternatif untuk pencegahan penyakit. Penelitian ini bertujuan untuk menguji pengaruh probiotik Bacillus cereus BR2 dengan prebiotik madu (sinbiotik monospesies), probiotik Staphylococcus lentus L1k dengan prebiotik madu (sinbiotik monospesies), probiotik B. cereus BR2 dan S. lentus L1k dengan prebiotik madu (sinbiotik multispesies) yang diberikan melalui pakan untuk pencegahan infeksi A. hydrophila pada ikan lele sangkuriang (Clarias gariepinus). Ikan uji dengan bobot awal (17,43 ± 0,22) g dipelihara selama 30 hari dan diberi pakan suplementasi, kemudian diuji tantang dengan bakteri A. hydrophila selama tujuh hari. Penelitian ini terdiri dari lima perlakuan dan tiga ulangan yaitu perlakuan A (BR2 1% + madu 0,5% + diuji tantang), B (L1k 1% + madu 0,5% + diuji tantang), C (BR2 0,5% + L1k 0,5% + madu 0,5% + diuji tantang), kontrol positif (tanpa probiotik dan prebiotik + diuji tantang), dan kontrol negatif (tanpa probiotik dan prebiotik + tanpa diuji tantang). Hasil penelitian menunjukkan sinbiotik monospesies dan multispesies mampu meningkatkan tingkat kelangsungan hidup, kinerja pertumbuhan, dan respons imun ikan lele untuk pencegahan infeksi A. hydrophila dengan hasil terbaik terdapat pada perlakuan sinbiotik multispesies., One of the bacterial diseases that threaten the increase in catfish production is Aeromonas hydrophila. The used of synbiotics which is a combination of probiotics and prebiotics is an alternative for disease prevention. This study aimed to examine the effect of probiotic Bacillus cereus BR2 with prebiotic honey (monospecies synbiotic), probiotic Staphylococcus lentus L1k with prebiotic honey (monospecies synbiotic), probiotic B. cereus BR2 and S. lentus L1k with prebiotic honey (multispecies synbiotic) through feed for the prevention of A. hydrophila bacterial infection to sangkuriang catfish (Clarias gariepinus). The fish size (17,43 ± 0,22) g were reared for 30 days and given supplementary feed, then challenged with A. hydrophila bacteria for seven days. This study consisted of five treatments and three replications i.e. treatment A (BR2 1% + honey 0,5% + challenged), B (L1k 1% + honey 0,5% + challenged), C (BR2 0,5% + L1k 0,5% + honey 0,5% + challenged), positive control (without probiotics and prebiotics + challenged), and negative control (without probiotics and prebiotics + no challenged). The results showed that monospecies and multispecies synbiotic could increase survival rate, growth performance, and immune respons of catfish to prevent of A. hydrophila infection with the best result found in the multispecies synbiotic treatment.
Keyword: Aeromonas hydrophila, Bacillus cereus BR2, Clarias gariepinus, Madu, Staphylococcus lentus L1k

Judul: Metrik Einstein (Anti-) Self-Dual Berdimensi Empat dengan Metode Cartan
Abstrak: Gravitational field equation can be formulated in differential forms (differential geometry), which describes gravity as a manifestation of the curvature of space-time. Curvature of space-time is characterized by a metric that satisfies the gravitational field equation. With differential forms it can be formulated the (anti-) self-dual Einstein equation, which is a modification of the Cartan structure in (anti-) self-dual basis. Calculation of (anti-) self-dual metric with (anti-) self-dual Einstein equation is simpler than the calculation using Christoffel symbols.
Keyword: