Judul: The effectiveness of the use of serotonin on the control of cannibalism of catfish fry (Clarias sp.) through feed
Abstrak: Catfish is one of the commodities that have great potential in freshwater fish farming. Catfish itself is a commonly cultivated fresh water commodity due to its numerous advantages. Consequently, the demand for fish consumption increased in line with population growth. However, there are several problems in catfish hatchery, one of which is the high mortality rate due to cannibalism among catfish fingerlings which results in a lack of fulfillment of catfish supply. Therefore, efforts were made to suppress the level of cannibalism in catfish fry by giving the serotonine hormone through their feed. This study aims to test the effectiveness of the serotonine hormone in controlling cannibalism. This research was conducted in 1 (one) replication using a field scale with two treatments. These treatment included the administration of serotonine at doses of 0.5 mg and 1 mg/kg of feed. The catfish fingerlings used in this study were 14-15 cm in size and were raised for 30 days at a stocking density of 1000 individuals per container. Eeeding was carried out 3 times a day, with ieach feeding consisting of 8% of the total fish weight. The administration of the serotonine hormone significantly reduced cannibalism among catfish fry with the best dose of the hormone serotonin 1 mg/kg of feed., Ikan lele merupakan salah satu komoditas yang memiliki potensi besar dalam budidaya ikan air tawar. Ikan lele merupakan komoditas budidaya air tawar yang banyak dibudidayakan, hal tersebut dikarenakan ikan lele memiliki banyak keunggulan, sehingga permintaan terhadap konsumsi ikan meningkat sejalan dengan peningkatan pertumbuhan jumlah penduduk. Namun, terdapat beberapa permasalahan dalam kegiatan pembenihan ikan lele, salah satunya adalah tingginya mortalitas akibat sifat kanibalisme pada benih ikan lele yang mengakibatkan kurangnya pemenuhan kebutuhan pasokan ikan lele. Maka dari itu dilakukan upaya dalam menekan tingkat kanibalisme pada benih ikan lele dengan pemberian hormon serotonin melalui pakan. Penelitian ini bertujuan untuk menguji tingkat efektifitas hormon serotonin dalam pengendalian kanibalisme. Penelitian ini dilakukan dalam 1 (satu) kali ulangan menggunakan skala lapangan dengan dua perlakuan. Perlakuan tersebut adalah pemberian serotonin dengan dosis 0,5 mg dan 1 mg/kg pakan. Benih ikan yang digunakan pada penelitian ini berukuran 14-15 cm yang dipelihara selama 30 hari dengan jumlah ikan 1000 ekor/ m2 dalam wadah yang terkontrol. Pola pemberian pakan pada tiap wadahnya yakni sebanyak 3 kali sehari sebanyak 8% dari total bobot ikan. Pemberian hormon serotonin berpengaruh nyata terhadap penekanan kanibalisme pada benih ikan lele dengan dosis terbaik pada pemberian hormon serotonin 1 mg/kg pakan.
Keyword: Benih ikan lele, Hormon serotonin, kanibalisme, Pakan

Judul: The effect of giving the hormone serotonin in feed in suppressing level of cannibalism in catfish (Clarias sp.)
Abstrak: Ikan lele (Clarias sp.) adalah komoditas perikanan air tawar banyak dibudidaya karena pertumbuhan yang cepat, toleransi terhadap fluktuasi kualitas air dan tahan penyakit. Peningkatan produksi ikan lele harus disertai dengan peningkatan produksi benih. Permasalahan yang terjadi dalam kegiatan pembenihan ikan lele adalah kanibalisme pada benih ikan lele ukuran 3–9 cm. Kanibalisme merupakan aktivitas membunuh dan mengkonsumsi seluruh atau sebagian dari individu sejenis. Penelitian ini bertujuan untuk mengkaji pengaruh hormon serotonin pada pakan dalam menekan tingkat kanibalisme pada ikan lele. Penelitian ini dilakukan dengan empat perlakuan dengan tiga ulangan yaitu, kontrol, P1 (serotonin 0,75 mg/kg pakan), P2 (serotonin 1 mg/kg pakan), P3 (serotonin 1,25 mg/kg pakan). Ikan lele berukuran 3–4 cm dipelihara selama 30 hari pada kontainer berukuran 60x40x40 cm dengan ketinggian air ±20 cm dan padat tebar 2 ekor per liter. Pemberian pakan dilakukan secara ad satiation sebanyak 3 kali sehari pada pukul 08.00, 14.00, dan 20.00 WIB. Parameter yang diamati meliputi kelangsungan hidup, total kanibalisme, tipe kanibalisme, dan kinerja pertumbuhan. Pemberian serotonin berpengaruh nyata terhadap penurunan tingkat kanibalisme pada benih ikan lele, dosis terbaik yaitu pemberian serotonin sebanyak 1,25 mg/kg pakan yang dapat menurunkan kanibalisme tipe I sebesar 77% pada benih ikan lele berukuran 3–4 cm., Catfish (Clarias sp.) is a freshwater fishery commodity that is widely cultivated because of the growth is relatively fast, tolerance to fluctuations of water quality, and quite resistant to disease. The increase in catfish production must be accompanied by an increase in seed production. The problem that occurs in catfish hatchery activities is cannibalism in catfish seeds. Cannibalism is the activity of killing and consuming all or part of an individual of the same species. This research aims to determine the effect of the hormone serotonin in feed in suppressing the level of cannibalism in catfish. This research was carried out by four treatments with three replications, namely, control, P1 (0.75 mg serotonin/kg feed), P2 (1 mg serotonin/kg feed), P3 (1.25 mg serotonin/kg feed). The 3–4 centimeters of catfish were kept in container measuring 60x40x40 cm with water height ±20 cm and density 2 seeds per liter. Feeding is carried out for three times a day with ad satiation method on 08.00 am, 14.00 pm, and 20.00 pm. Parameters observed included survival, total cannibalism, type of cannibalism, and growth performance. Providing serotonin has a significant effect on reducing the level of cannibalism in catfish fry with the best dose at 1.25 mg serotonin/kg feed That can decrease type I cannibalism by 77%.
Keyword: Benih Ikan Lele, Kanibalisme, Pakan, Serotonin, Agresivitas

Judul: Penentuan Nilai Eigen dan Vektor Eigen dari Matriks Tridiagonal 2-Toeplitz dengan Pendekatan Polinomial Chebyshev
Abstrak: The eigenvalues and eigenvectors of a matrix can be determined by finding its characteristic polynomials. The characteristic polynomials of a tridiagonal 2-Toeplitz matrix is shown to be closely connected to polynomials which satisfy the Chebyshev recurrence relationship. If the order of the matrix is odd, then the eigenvalues are found explicitly in terms of the Chebyshev zeros and the eigenvectors are found in terms of the polynomials satisfying the recurrence relationship. For even ordered matrices, the situation is more complicated. The problem in these cases is that although the Chebyshev recurrence formula is still applied, its initial values are not generating Chebyshev polynomials
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