Judul: Performa anak domba lokal kembar yang mendapat suplementasi kobalt dan konsorsium bakteri rumen selama periode prasapih
Abstrak: Bakteri rumen membutuhkan kobalt (Co) untuk pertumbuhan dan sintesis vitamin B12, dan konsentrasinya dalam media pertumbuhan merupakan faktor pembatas untuk produksi vitamin B12. Meskipun demikian, Co dalam konsentrasi tinggi juga menimbulkan efek merugikan bagi pertumbuhan bakteri. Tujuan penelitian ini adalah mengkaji toleransi konsorsium bakteri rumen yang ditumbuhkan dalam media berkadar Co tinggi dan menentukan kemampuannya dalam mensintesis vitamin B12. Tahapan penelitian adalah: 1) penentuan pola pertumbuhan isolat bakteri rumen, 2) penentuan pola pertumbuhan dan populasi konsorsium bakteri rumen, dan 3) kajian adaptasi konsorsium bakteri rumen dalam media berkadar Co tinggi dan kemampuan sintesis vitamin B12. Isolat bakteri rumen yang digunakan merupakan koleksi Laboratorium Ilmu Nutrisi Ternak Perah Fakultas Peternakan IPB. Dosis Co dalam media adalah 100, 200, 300, 400 dan 500 ppm. Peubah yang diamati adalah pola pertumbuhan 6 isolat bakteri, pH media, bahan kering (BK), populasi konsorsium bakteri rumen dan kadar vitamin B12. Hasil penelitian memperlihatkan bahwa penambahan Co dengan konsentrasi mencapai 500 ppm masih toleran bagi pertumbuhan bakteri rumen tetapi belum mampu meningkatkan sintesis vitamin B12.
Keyword: bakteri rumen, kobalt, vitamin B12

Judul: Pertumbuhan Bakteri dan Kecernaan Pakan in Vitro sebagai Indikator Adaptasi Isolat Bakteri Rumen Kerbau dalam Media yang Mengandung Kobalt Berbeda
Abstrak: Unsur mineral kobalt (Co) merupakan mineral esensial dan komponennya yang dapat disintesis oleh mikroorganisme termasuk bakteri rumen menjadi vitamin B12. Suplementasi Co dapat meningkatkan pembentukan vitamin B12 dan perkembangan mikroba rumen. Mikroba rumen sangat penting dalam proses pencernaan pakan dan penyediaan protein pada ruminansia. Pertumbuhan mikroba dalam rumen sangat tergantung pada ketersediaan, jumlah, maupun kualitas nutrien dalam pakan. Ketersediaan mineral termasuk salah satu faktor yang mempengaruhi pertumbuhan mikroba. Kajian tentang isolat bakteri sudah dilakukan oleh Astuti (2010) dan Gayatri (2010) hasilnya menunjukkan bahwa sebanyak 12 isolat mampu mendegradasi serat kasar. Namun informasi mengenai adaptasi isolat mengenai adaptasi isolat bakteri terhadap mineral tinggi kobalt (Co) masih terbatas. Kemampuan adaptasi terhadap kadar kobalt (Co) tinggi diperkirakan terkait dengan kemampuan isolat mikroba dengan sintesis vitamin B12 (cyanocobalamin). Tujuan penelitian ini adalah untuk mengkaji batas toleransi isolat bakteri diisolasi dari rumen kerbau pada media berkadar kobalt bervariasi dan untuk mengetahui kecernaan dengan penggunaan calf starter dan isolat bakteri campuran.
Keyword: nutrient digestibility in vitro, rumen bacteria isolats, completely randomized design, dry cell bacteria, analysis of variant, contrast orthogonal test

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