Judul: Kinerja Pertumbuhan Ikan Bawal Air Tawar (Colossoma macropomum) yang Diberi Makan Timol
Abstrak: Ikan bawal air tawar (Colossoma macropomum) merupakan komoditas ikan air tawar yang dibudidaya di Indonesia. Penelitian ini bertujuan mengevaluasi pengaruh pemberian thymol dengan dosis yang berbeda pada pakan terhadap kinerja petumbuhan ikan bawal. Penelitian menggunakan empat perlakuan dengan penambahan dosis thymol sebesar 0,0, 0,2, 0,4, dan 0,6 g/kg pakan. Setiap perlakuan diulang sebanyak empat kali. Benih ikan bawal bobol 8,22±0,01 g dipelihara dalam akuarium berukuran 90x45x45 cm dengan tinggi air 30 cm. Setiap akuarium diisikan sebanyak 15 ekor ikan bawal untuk kemudian dipelihara selama 70 hari. Hasil penelitian menunjukkan bahwa pemberian pakan ditambah thymol sebanyak 0,6 g/kg berpengaruh nyata (p<0,05) terhadap perlakuan lainnya dan dapat meningkatkan kinerja pertumbuhan ikan seperti nilai total biomassa akhir, bobot rata-rata akhir, rasio efisiensi protein dan laju pertumbuhan spesifik serta dapat meningkatkan status antioksidan ikan bawal., Tambaqui (Colossoma macropomum) is a freshwater fish commodity cultivated in Indonesia. This study aims to evaluate the effect of giving thymol at different doses in feed on the growth performance of tambaqui. The study used four treatments with additional thymol doses of 0.0, 0.2, 0.4, and 0.6 g/kg feed. Each treatment was repeated four times. Tambaqui fry weighing 8.22±0.01 g were maintained in an aquarium measuring 90x45x45 cm with a water height of 30 cm. Each aquarium was filled with 15 tambaqui to be kept for 70 days. The results of the study showed that feeding added with thymol at 0.6 g/kg had a significant effect (p<0.05) on other treatments and could improve fish growth performance, such as final total biomass value, final average weight, protein efficiency ratio, and specific growth rate, and could increase the antioxidant status of tambaqui.
Keyword: Growth, tambaqui, thymol

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: 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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