Judul: Growth Performance, Immune Response, and Resistance of Nile Tilapia Fed Bacillus sp. NP5 Paraprobiotic and infected by Streptococcus agalactiae
Abstrak: Penelitian ini bertujuan untuk mengevaluasi efektivitas pemberian paraprobiotik Bacillus sp. NP5 yang ditambahkan melalui pakan pada kinerja pertumbuhan, respons imun, dan resistansi ikan nila terhadap infeksi Streptococcus agalactiae. Penelitian ini menggunakan rancangan acak rengkap yang terdiri dari 3 perlakuan 5 ulangan, penambahan probiotik 1%, penambahan paraprobiotik 1% dan tanpa penambahan probiotik atau paraprobiotik (kontrol). Ikan perlakuan dipelihara selama 30 hari, pada hari ke 31, uji tantang dengan S. agalactiae (107 CFU ml-1) yang diinjeksikan melalui intraperitoneal kecuali perlakuan kontrol negatif yang diinjeksi dengan PBS. Hasil penelitian setelah 30 hari pemberian probiotik dan paraprobiotik Bacillus sp. NP5 menunjukkan kinerja pertumbuhan dan respons imun yang meningkat signifikan (P<0.05) dibandingkan dengan kontrol. Pasca uji tantang, peningkatan respons imun pada perlakuan probiotik dan paraprobiotik Bacillus sp. NP5 menunjukkan tingkat kelangsungan hidup yang lebih tinggi (P<0.05) dibandingkan kontrol positif pasca uji tantang dengan S. agalactiae. Pemberian probiotik dan paraprobiotik Bacillus sp. NP5 melalui pakan efektif dalam meningkatkan kinerja pertumbuhan, respons imun, dan resistansi ikan nila terhadap infeksi Streptococcus agalactiae., The aim of this study was to evaluate the effectiveness of paraprobiotic Bacillus sp. NP5 administration through commercial feed on the growth performances, immune responses, and resistance of nile tilapia against Streptococcus agalactiae infection. This study used a completely randomized design, which consisted of three treatments with five repetitions, that were 1% (v/w) addition of probiotic, 1% (v/w) addition of paraprobiotic, and no addition of probiotic or paraprobiotic (control). The experimental fish were reared for 30 days and on day 31, the fish was challenge tested with S. agalactiae (107 CFU ml-1) injected by intraperitoneal route, unless the negative control was injected with PBS. The results of this study showed significantly improved growth performances and immune responses (P<0.05), compared to the control group after 30 days of probiotic and paraprobiotic Bacillus sp. NP5 administered. After challenge tested, the increased of immune responses in the probiotic and paraprobiotic of Bacillus sp. NP5 showed a higher survival rate (P<0.05), than positive control after callenge tested with S. agalactiae. Administration of probiotic and paraprobiotic Bacillus sp. NP5 through the commercial feed were effective in increase the growth performances, immune responses, and resistance of nile tilapia against S. agalactiae infection.
Keyword: Bacillus sp. NP5, nile tilapia, paraprobiotic, Streptococcus agalactiae

Judul: Application of Bacillus cereus BR2, Honey, and the combination of both for prevention of Streptococcus agalactiae infection in saline nile tilapia (Oreochromis niloticus)
Abstrak: Ikan nila merupakan komoditas unggulan yang dibudidayakan secara intensif dan berpeluang terserang penyakit Streptococcus agalactiae. Upaya pencegahan yang dapat dilakukan untuk mengurangi dampak serangan bakteri S. agalactiae adalah dengan pakan suplementasi menggunakan probiotik, prebiotik, dan sinbiotik. Penelitian ini bertujuan untuk menguji pengaruh pemberian probiotik Bacillus cereus BR2, prebiotik madu randu, dan gabungan keduanya melalui pakan untuk pencegahan infeksi S. agalactiae. Penelitian ini terdiri atas lima perlakuan dan tiga ulangan yaitu A (B. cereus BR2 109 CFU mL-1 1%), B (madu randu 1%), C (B. cereus BR2 109 CFU mL-1 1% + madu randu 1%), K+ dan K- (tanpa suplementasi). Ikan uji yang digunakan adalah ikan nila nirwana 3 dengan bobot rata-rata 15,13±1,74 g. Ikan diaklimatisasi terlebih dahulu ke air payau secara bertahap hingga salinitas 10 ppt dalam akuarium berukuran 60×30×40 cm3 dengan kepadatan 10 ekor per akuarium (450 ekor m-3 ). Selama 30 hari pemeliharaan, ikan diberi pakan komersil yang telah disuplementasi sebanyak 3 kali sehari sekenyangkenyangnya. Hasil penelitian menunjukkan bahwa tingkat kelangsungan hidup, kinerja pertumbuhan, dan respon imun ikan nila salin yang diberi perlakuan suplementasi pakan probiotik B. cereus BR2 dan prebiotik madu randu lebih baik dan berbeda nyata (P<0,05) dibandingkan perlakuan kontrol. Pemberian sinbiotik B. cereus BR2 dan madu melalui suplementasi pakan dapat meningkatkan kinerja pertumbuhan dan respons imun ikan ikan nila salin., Tilapia is the main commodity that is cultivated intensively and has the potential to be infected by Streptococcus agalactiae. Prevention efforts that can be done to reduce the impact of S. agalactiae attack are by supplementing feed using probiotics, prebiotics, and synbiotics. This study aimed to examine the effect of giving Bacillus cereus BR2 probiotic, honey prebiotic, and a combination of both through the feed for the prevention of S. agalactiae infection. This study consisted of five treatments and three replications, namely A (B. cereus BR2 109 CFU mL-1 1%), B (kapok honey 1%), C (B. cereus BR2 109 CFU mL-1 1% + kapok honey 1 %), K+ and K- (without supplementation). The test fish used were nile tilapia with an average weight of 15.13±1.74 g. The fish were first acclimatized to brackish water gradually to 10 ppt. salinity in an aquarium measuring 60×30×40 cm9 with a density of 10 fish per aquarium (450 fish m-3 ). During the 30 days of rearing, the fish were given commercial feed which had been supplemented 3 times a day as full as possible. The results showed that the survival rate, growth performance, and immune response of saline tilapia which were treated with B. cereus BR2 probiotic feed supplementation and prebiotic kapok honey were better and significantly different (P<0.05) than the control treatment. The application of B. cereus BR2 and kapok honey synbiotic through feed supplementation can improve growth performance and immune response of saline tilapia.
Keyword: Bacillus cereus BR2, honey, Streptococcus agalactiae, tilapia, ikan nila salin, madu

Judul: Characteristic of Overshooting Top (OT) Based on  Himawari  8  Satellite  as  a  Convective  Cloud  Feature  that  Generates  Extreme Weather in the Java Island Region
Abstrak: Overshooting Top (OT) is a feature at the top of a convective cloud that is associated with extreme weather. Research on OT in tropical Indonesia is still very limited. The existence of geostationary satellites with wide area coverage and fast frequency observations is useful for observing the fast dynamics of the OT life cycle. Therefore, this study intends to analyze the relationship between OT and extreme weather, updraft and thermodynamic conditions of OT when extreme weather occurs, the best objective method for detecting OT in the day time and night time, and the spatiotemporal distribution of OT in the tropical region of Java Island during the 2018-2021 period. Based on visual analysis using visible channel and Himawari 8 sandwich products, 87% of extreme weather events in Java were accompanied by the appearance of OT. It indicates that the presence of the OT pattern is a convection cloud pattern or feature that is closely related to extreme weather events for the Java Island region. The existence of a time lag between the appearance of OT and extreme weather events on Java Island indicates that the OT of convection cloud can be used as a precursor or nowcasting for the appearance of extreme weather. Most of the convective cloud OT features during extreme weather events on Java Island have altitude that were only able to exceed the altitude of the equilibrium level and few were able to exceed the tropopause level of 9 km – 16 km. The difference in atmospheric conditions during extreme weather events on Java Island, which is in the tropics and subtropics, is a strong and unstable convective energy condition characterized by a larger CAPE, as well as unstable KI, LI, SI and TTI values. It is offset by kinematic factors in the form of a weak vertical wind shear (bulk wind shear 0-6 km) and a higher freezing point height. The difference between extreme weather events in the Java Island region and other tropical regions compared to subtropical regions is the strong updraft speed of convection clouds. The IRW Texture COMB algorithm based on the IRW-Texture Gradient modification and the COMB algorithm shows a significant increase in quality for detecting OT and non-OT pixels in Java. Rainy days with rainfall > 50 mm/day are very common in areas with an altitude of > 500 m. On the other hand, the level of convection activity which is indicated by the presence of OT and lightning is significantly reduced in this area. OT of convective clouds appear more frequently during the DJF season and less frequently during the JJA season. OT often appears during the day time and rarely at night time. Most OTs appear in the central part, away from the south and north coasts of Java Island during the day, while OTs that appear near the south and north coasts of Java Island can appear in the morning or afternoon.
Keyword: convective clouds, extreme weather, Overshooting Tops, Himawari 8 Satellite