Judul: Maskulinisasi Ikan Lele Clarias sp. Melalui Suplementasi Serbuk Sari Pinus dalam Pakan
Abstrak: Ikan lele (Clarias sp.) merupakan ikan konsumsi yang banyak dibudidayakan di Indonesia. Pemijahan buatan pada ikan lele mengharuskan membunuh ikan jantan karena tidak dapat distripping, kondisi tersebut mengakibatkan ketersediaan jantan semakin lama semakin berkurang sehingga ketersediaan ikan jantan sangat penting untuk pemenuhan kebutuhan tersebut. Sex reversal (maskulinisasi) merupakan metode yang dilakukan untuk membuat jumlah ikan lele jantan lebih banyak yang kemudian dipersiapkan sebagai calon induk. Tujuan penelitian ini adalah menentukan dosis optimal serbuk sari pinus untuk maskulinisasi ikan lele. Benih ikan lele yang digunakan berumur 7 hari dengan kepadatan 30 ekor per 50 liter air dan diberi perlakuan selama 60 hari. Terdapat empat perlakuan berbeda, kontrol (tanpa penambahan serbuk sari pinus), serbuk sari pinus 0,3 g/kg pakan, serbuk sari pinus 0,5 g/kg pakan, dan serbuk sari pinus 0,7 g/kg pakan. Hasil penelitian menunjukkan bahwa persentase kelamin jantan pada perlakuan 0,3 g/kg sebesar 66,67±11,55%, dosis 0,5 g/kg sebesar 76,67±11,55%, dosis 0,7 g/kg sebesar 73,33±5,77 %, dan perlakuan kontrol sebesar 50±10%. Berdasarkan data hasil persentase kelamin jantan diketahui bahwa perlakuan terbaik terdapat pada dosis 0,5 g/kg (P<0,05). Suplementasi serbuk sari pinus dengan dosis yang berbeda dalam pakan dapat memaskulinisasi benih ikan lele., Catfish (Clarias sp.) is a consumption fish that is widely cultivated in Indonesia. Artificial spawning in catfish requires killing male fish because they cannot be stripped, this condition results in the availability of males decreasing over time so that the availability of male fish is very important to meet these needs. Sex reversal (masculinization) is a method used to make a larger number of male catfish which are then prepared as prospective broodstock. The purpose of this study was to determine the optimal dose of pine pollen for masculinization of catfish. The catfish seeds used were 7 days old with a density of 30 fish per 50 liters of water and were treated for 60 days. There were four different treatments, control (without the addition of pine pollen), pine pollen 0,3 g/kg feed, pine pollen 0,5 g/kg feed, and pine pollen 0,7 g/kg feed. The results showed that the percentage of male sex in the 0,3 g/kg treatment was 66,67 ± 11,55%, the dose of 0,5 g/kg was 76,67 ± 11,55%, the dose of 0,7 g/kg was 73,33 ± 5,77%, and the control treatment was 50 ± 10%. Based on the data on the percentage of male sex it is known that the best treatment is at a dose of 0,5 g/kg (P<0,05). Supplementation of pine pollen with different doses in feed can masculinize catfish seeds.
Keyword: male, pine pollen, sex reversal

Judul: The use of a combination of pine (Pinus merkusii) extract and powder in masculinization of red tilapia (Oreochromis sp.)
Abstrak: Ikan nila jantan memiliki pertumbuhan yang lebih cepat dibandingkan dengan ikan nila betina. Maskulinisasi pada ikan nila dilakukan untuk mempercepat masa produksi ikan dengan metode budidaya monoseks. Proses maskulinisasi dapat dilakukan dengan pemberian hormon androgen untuk menginduksi pengarahan kelamin jantan pada ikan. Penelitian ini bertujuan untuk mengetahui efektivitas penggunaan ekstrak dan serbuk buah pinus dengan metode perendaman dan suplementasi dalam pakan pada larva ikan nila berumur 5 hari selama 60 hari pemeliharaan. Terdapat empat perlakuan yaitu perendaman dengan ekstrak buah pinus dosis 0,2 ml.L-1 air selama 10 jam (I), perendaman dengan ekstrak buah pinus dan suplementasi serbuk buah pinus dalam pakan dosis 0,5 g/kg pakan (IS0,5), perendaman dengan ekstrak buah pinus dan suplementasi serbuk buah pinus dalam pakan pakan dosis 1g/kg pakan (IS 1,0) dibandingkan dengan perlakuan kontrol tanpa penggunaan ekstrak maupun serbuk buah pinus (K). Nilai nisbah kelamin jantan tertinggi yang dihasilkan yaitu pada perlakuan IS 1,0 sebesar 74,17±1,67%, dibandingkan dengan perlakuan IS 0,5 sebesar 66,67±7,20%, perlakuan I sebesar 61,67 ± 4,30% dan perlakuan kontrol sebesar 55,00±7,93 %. Berdasarkan penelitian ini, perlakuan terbaik terdapat pada perlakuan IS 1,0 dengan perbedaan sebesar 19.17% dibandingkan perlakuan kontrol. Sintasan ikan tertinggi yang didapatkan pada perlakuan IS 1,0 memiliki nilai sebesar 95,5±1,0 %, Male tilapia fish have faster growth compared to female tilapia. Masculinization in tilapia is performed to accelerate fish production using the monosex culture method. The masculinization process can be achieved by administering androgen hormones to induce male sex determination in the fish. This study aims to determine the effectiveness of using pine fruit extract and powder through immersion and supplementation methods in the diet of 5-day-old tilapia larvae for a 60-day rearing period. There are four treatments: immersion with pine fruit extract at a dosage of 0.2 ml/L of water for 10 hours (I), immersion with pine fruit extract and supplementation of pine fruit powder in the diet at a dosage of 0.5 g/kg of feed (IS 0.5), immersion with pine fruit extract and supplementation of pine fruit powder in the diet at a dosage of 1 g/kg of feed (IS 1.0), compared to the control treatment without the use of extract or pine fruit powder (K). The highest male sex ratio obtained was in the IS 1.0 treatment, which amounted to 74.17 ± 1.67%, compared to the IS 0.5 treatment at 66.67 ± 7.20%, the I treatment at 61.67 ± 4.30%, and the control treatment at 55.00 ± 7.93%. Based on this study, the best treatment was found in the IS 1.0 treatment with a difference of 19.17% compared to the control treatment. The highest fish survival rate obtained in the IS 1.0 treatment was 95.5 ± 1.0%.
Keyword: Nila, maskulinisasi, buah pinus, 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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