Electronic Theses and Dissertation

Rotifera (brachionus plicatilis) merupakan salah satu pakan alami yang banyak dimanfaatkan dalam kegiatan pembenihan ikan karena memiliki ukuran yang sesuai dengan bukaan mulut larva serta kandungan nutrisi yang mendukung pertumbuhan. produksi rotifera yang belum optimal masih menjadi kendala sehingga diperlukan upaya untuk meningkatkan produktivitasnya melalui pemberian pakan kombinasi nannochloropsis sp., ragi, dan terasi. penelitian ini bertujuan mengetahui pengaruh pakan kombinasi terhadap pertumbuhan rotifera serta menentukan dosis yang paling efektif. penelitian menggunakan rancangan acak lengkap (ral) dengan empat perlakuan dan empat ulangan, yaitu p0 (kontrol), p1 (nannochloropsis sp. + ragi 15 mg/l + terasi 0,5 g/l), p2 (nannochloropsis sp. + ragi 15 mg/l + terasi 1 g/l), dan p3 (nannochloropsis sp. + ragi 15 mg/l + terasi 1,5 g/l). parameter yang diamati meliputi kepadatan populasi, laju pertumbuhan, kandungan protein, dan kualitas air. hasil penelitian menunjukkan bahwa perlakuan berpengaruh nyata terhadap kepadatan populasi dan laju pertumbuhan rotifera. perlakuan p1 menghasilkan kepadatan populasi tertinggi sebesar 167,00±5,72 ind/ml dan laju pertumbuhan tertinggi sebesar 0,2400±0,0003 ind/ml/hari. kandungan protein tertinggi diperoleh pada p3 sebesar 7,24%, sedangkan terendah pada p0 sebesar 4,36%. selama penelitian, kualitas air masih mendukung pertumbuhan rotifera dengan suhu 28,4–31,5°c, ph 7,4–8,2, salinitas 29–30 ppt, do 3,9–5,7 mg/l, dan amonia 0,06–0,18 mg/l. berdasarkan hasil penelitian, dosis terasi 0,5 g/l merupakan perlakuan paling efektif untuk meningkatkan kepadatan populasi dan laju pertumbuhan rotifera secara lebih optimal. kata kunci: brachionus plicatilis, nannochloropsis sp., ragi, terasi, laju pertumbuhan.

Rotifers (Brachionus plicatilis) are a widely used natural feed in fish hatcheries due to their size, which suits larval mouth openings, and their nutritional content that supports growth. Suboptimal rotifer production remains a challenge, necessitating efforts to enhance productivity through a combined diet of Nannochloropsis sp., yeast, and shrimp paste. This study aimed to determine the effect of this combined diet on rotifer growth and to identify the most effective dosage. A Completely Randomized Design (CRD) was employed with four treatments and four replicates: P0 (control), P1 (Nannochloropsis sp. + yeast 15 mg/L + shrimp paste 0.5 g/L), P2 (Nannochloropsis sp. + yeast 15 mg/L + shrimp paste 1 g/L), and P3 (Nannochloropsis sp. + yeast 15 mg/L + shrimp paste 1.5 g/L). Observed parameters included population density, growth rate, protein content, and water quality. The results indicated that the treatments significantly affected rotifer population density and growth rate. Treatment P1 yielded the highest population density (167.00 ± 5.72 ind/mL) and the highest growth rate (0.2400 ± 0.0003 ind/mL/day). The highest protein content was observed in P3 (7.24%), while the lowest was in P0 (4.36%). Throughout the study, water quality parameters remained conducive to rotifer growth: temperature 28.4–31.5°C, pH 7.4–8.2, salinity 29–30 ppt, DO 3.9–5.7 mg/L, and ammonia 0.06–0.18 mg/L. Based on the findings, a shrimp paste dosage of 0.5 g/L was the most effective treatment for optimizing rotifer population density and growth rate. Keywords: Brachionus plicatilis, Nannochloropsis sp., yeast, shrimp paste, growth rate.