Judul: Population of intestinal microflora, digestive enzyme activity and growth of catfish Clarias sp. were given by probiotic Bacillus megaterium
Abstrak: Kegiatan budidaya ikan secara intensif memiliki banyak permasalahan diantaranya kecernaan pakan yang rendah, serangan penyakit yang meningkat dan kualitas air yang menurun. Kecernaan pakan dalam budidaya ikan memiliki peran penting dalam keberhasilan proses budidaya. Kecernaan pakan berpengaruh terhadap pertumbuhan ikan dan biaya produksi dalam proses budidaya. Kecernaan pakan dapat ditingkatkan dengan meningkatkan enzim-enzim pencernaan yang mampu merombak nutrien dalam pakan. Peningkatan enzim-enzim pencernaan dapat dilakukan dengan memanfaatkan bakteri probiotik. Probiotik memiliki kemampuan dalam menghasilkan enzim-enzim pencernaan yang dapat meningkatkan kecernaan pakan dan pertumbuhan ikan. Penelitian ini bertujuan untuk mengevaluasi pengaruh pemberian bakteri probiotik terhadap populasi mikroflora intestinal, aktivitas enzim pencernaan dan pertumbuhan ikan lele., An increase in disease, low digestibility of feed, and a decrease in water quality are several problems in intensive fish farming. Digestibility of feed in aquaculture also has a high impact to the fish growth and production cost, which are affecting to the success of the farming. Actually, this can be improved by developing the activity of digestive enzymes to break down the nutrients in the feed. The effort to increase digestive enzymes activity can be done by using probiotic bacteria. Probiotic has an ability to produce digestive enzymes to improve digestibility and growth of fish. This study aimed to analyze the effect of probiotic bacteria on the population of intestinal microflora, digestive enzyme activities and growth of catfish.
Keyword: Digestive enzyme activity, Microflora intestinal, Growth, Probiotic

Judul: Effect of Addition of Probiotic Bacillus NP5 in  Biofloc System on Growth and Health Status of Catfish Juvenile Clarias sp.
Abstrak: Teknologi bioflok telah diketahui dapat menurunkan kadar amonia pada media pemeliharaan budidaya sistem intensif dan probiotik Bacillus NP5R telah diketahui dapat meningkatkan pertumbuhan dan tingkat kelangsungan hidup melalui peningkatan efisiensi pencernaan dan kesehatan ikan. Penelitian bertujuan mengevaluasi penambahan probiotik Bacillus NP5R pada sistem bioflok dalam meningkatkan kinerja pertumbuhan dan status kesehatan benih lele Clarias sp.. Penelitian menggunakan rancangan acak lengkap (RAL) dengan tiga perlakuan dan tiga ulangan, yaitu ikan dipelihara tanpa aplikasi bioflok dan penambahan probiotik Bacillus NP5R (K), ikan dipelihara dengan sistem bioflok (BF), dan ikan dipelihara dalam sistem bioflok dengan penambahan probiotik Bacillus NP5R (BFP). Larva lele dengan panjang rata-rata 0,83±0,00 cm dan bobot rata-rata 0,02±0,01 g dipelihara dengan padat tebar 300 ekor/akuarium selama 30 hari. Parameter yang diamati meliputi pertumbuhan panjang mutlak, laju pertumbuhan harian, rasio konversi pakan, koefisien keragaman, kelimpahan bakteri Bacillus NP5R , total eritrosit, total leukosit, kadar hemoglobin, kadar hematokrit, dan tingkat kelangsungan hidup. Hasil penelitian menunjukkan bahwa penambahan probiotik Bacillus NP5R dalam sistem bioflok dapat meningkatkan laju pertumbuhan 5%, tingkat kelangsungan hidup 15%, dan status kesehatan benih lele yang menunjukkan hasil terbaik dibandingkan perlakuan lainnya. Penerapan sistem bioflok dengan penambahan Bacillus NP5R diharapkan menjadi alternatif solusi untuk mengurangi limbah amonia pada budidaya ikan lele., Biofloc technology has been known to reduce ammonia levels in aquaculture’s intensive system maintenance media and the probiotic Bacillus NP5R has been known to increase growth and survival rates through improved digestive efficiency and fish health. This study aimed to evaluate the addition of probiotic Bacillus NP5R in the biofloc system in improving growth and health status of catfish juvenile Clarias sp.. This study used a complete randomized design (RAL) of three treatments and three replications, namely fish reared without biofloc system and without addition of probiotic Bacillus NP5R (K), fish reared in a biofloc system (BF), and fish reared in a biofloc system with the addition of probiotic Bacillus NP5R (BFP) within 30 days of treatment. The larvae that used had an average length of 0,83±0,00 cm and an average weight of 0,02±0,01 g with a stocking density of 300 individuals per aquarium. Parameters observed during the study included absolute length growth, daily growth rate, feed conversion ratio, coefficient of diversity, abundance of Bacillus NP5R bacteria, total erythrocytes, total leukocytes, hemoglobin levels, hematocrit levels, and survival rates. The results showed that the addition of the probiotic Bacillus NP5R in the biofloc system can increase the growth rate by 5%, survival rate by 15%, and the health status of catfish juvenile which showed the best results compared to other treatments. The application of the biofloc system with the addition of Bacillus NP5R is expected to be an alternative solution to reduce ammonia waste in catfish farming.
Keyword: Bacillus NP5R, biofloc, Clarias sp., growth, health status

Judul: : Persamaan Tunggal sebagai Representasi Kurva Komposit
Abstrak: A mathematical method is introduced to represent a composite curve based on an extension of analytic geometry. The representation is given either with a single equation or with two equations, in the case of parametric representation. This method permits the representation of composite curves in similar manner to the conventional representation of non-composite curves. Some mathematical tools, including Heaviside unit step function and periodizer function, are used in the establishment of a single equation. In this paper, regular equations of regular and irregular polygon, as well as composite curves of two dimensions, are implemented using a computer algebraic system, Mathematica.
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