Judul: Growth and Production Performance of Tambaqui Colossoma macropomum Given Different Commercial Feeds in Cirata Reservoir, West Java.
Abstrak: Keberhasilan budidaya intensif salah satunya ditentukan oleh kualitas pakan. Pakan berkontribusi besar dalam biaya produksi hingga mencapai 60-80%. Penelitian ini bertujuan membandingkan pengaruh lima produk pakan komersial berbeda terhadap kinerja pertumbuhan dan produksi ikan bawal (Colossoma macropomum) yang dipelihara di keramba jaring apung di Waduk Cirata. Penelitian ini menggunakan lima produk pakan komersial yaitu pakan komersial A dengan kadar protein (28,11%), pakan komersial B (28,56%), pakan komersial C (26,33%), pakan komersial D (28,11%), dan pakan komersial E (31,68%). Ikan dengan ukuran awal 10±0,1 g, dipelihara di keramba jaring apung berukuran 7 m × 7 m × 3,5 m dengan padat tebar 24 ekor/m³ selama 83 hari dengan frekuensi pemberian pakan sebanyak dua kali sehari, yaitu pukul 08.0˗009.00 dan 16.00˗17.00 secara ad satiation. Hasil penelitian menunjukkan bahwa pakan E dengan kadar protein 31,68% memberikan nilai biomassa akhir, bobot rata-rata, laju pertumbuhan harian, retensi protein, dan retensi lemak tertinggi, serta feed cost per gain dan nilai konversi pakan terendah dibandingkan lima perlakuan lainnya. Berdasarkan hasil penelitian ini dapat disimpulkan kinerja pertumbuhan dan produksi ikan bawal (Colossoma macropomum) tertinggi dan feed cost per gain terbaik diperoleh pada perlakuan pakan komersial E yang memiliki protein sebesar 31,68%., The success of intensive cultivation is determined by the quality of feed. Feed contributes greatly to production costs up to 60-80%. This study aimed to compare the effect of five different commercial feed products on the growth and production performance of tambaqui (Colossoma macropomum) reared in floating net cages in Cirata Reservoir. This study used five product commercial feeds, namely commercial feed A with protein content (28.11%), commercial feed B (28.56%), commercial feed C (26.33%), commercial feed D (28.11%), and commercial feed. E (31.68%). Fish with an initial size of 10±0.1 g were kept in floating net cages measuring 7 m × 7 m × 3.5 m with a stoking density of 24 fish/m for 83 days with the frequency of feeding twice a day, at 08.0˗ 009.00 and 16.00-17.00 with ad satiation. The results showed that feed E with a protein content of 31.68% gave the highest final biomass value, average weight, daily growth rate, protein retention, and fat retention, as well as the lowest feed cost per gain and feed conversion value compared to the other five treatments. Based on the results of this study, it can be concluded that the highest growth and production performance of tambaqui (Colossoma macropomum) and the best feed cost per gain were obtained in commercial feed treatment E which has a protein of 31.68%.
Keyword: ikan bawal, keramba jaring apung, komersial, pakan, pertumbuhan

Judul: Kinerja pertumbuhan ikan mas (Cyprinus carpio) yang diberi pakan komersial berbeda di Waduk Cirata, Jawa Barat
Abstrak: Budidaya yang di intensifikasiikan intensif memerlukan pakan komersial yang berkualitas tinggi dengan, kandungan nutrien yang tepat untuk menunjang pertumbuhan. Penelitian ini bertujuan membandingkan pakan komersial berbeda terhadapkinerja pertumbuhan ikan mas (Cyprinus carpio) yang dipelihara di keramba jarring apung (KJA) di Waduk Cirata, Jawa Barat dengan pemberian pakan komersial berbeda. Penelitian ini menggunakan empat pakan komersial yang berbeda, yaitu:, pakan komersial A (kadar protein ? 28,10%), perlakuan B (kadar protein 28,80%), perlakuan C (kadar protein 28,90%), dan perlakuan D (kadar protein 29,12%). Bobot rata-rata ikan yang digunakan pada awal tebar adalah 23 g, petakan KJA yang digunakan pada KJA berukuran 3 × 3 × 3 m. Frekuensi pemberian pakan adalah tiga kali sehari (08.00, 12.00, 17.00) dengan, pemberian pakan secara at satiation selama 100 hari pemeliharaan. Hasil penelitian menunjukkan bahwa perlakuan D (29,12%) memberikan performa biomassa akhir, bobot rata-rata, laju pertumbuhan spesifik, serta feed cost per gain dan nilai konversi pakan terbaik terendah dibandingkan tiga3 perlakuan lainnya. Berdasarkan hasil penelitian yang diperoleh dapat disimpulkan kinerja pertumbuhan tertinggi didapatkan pada perlakuan pakan komersial DD dengan kadar protein 29,12%., Intensified aquaculture requires high quality commercial feeds that contain the right nutrients to support growth. This study aims to compare different commercial feeds for carp (Cyprinus carpio) reared in floating jarring cages in Cirata Reservoir, West Java. This study used four different commercial feeds, namely, commercial feed A (protein content 28.10%), treatment B (protein content 28.80%), treatment C (protein content 28.90%), treatment D (protein content 29.12%). The average weight of fish used at the beginning of stocking was 23 g. The plot used in the KJA was 3 × 3 × 3 m in size. The frequency of feeding is three times a day (08.00, 12.00, 17.00), feeding at satiation for 100 days of maintenance. The results of the study treatment D (29.12%) gave the best performance of final biomass, average weight, specific growth rate, as well as feed cost per gain and the best feed conversion value compared to the other 3 treatments. Based on the results obtained, it can be concluded that the highest growth performance was obtained in the commercial feed treatment D with a protein content of 29.12%.
Keyword: ikan mas, kadar protein, keramba jaring apung, pakan komersial

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.
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