Ikan patin (pangasius sp.) merupakan komoditas ikan air tawar yang memiliki nilai ekonomis tinggi. usaha meningkatkan laju pertumbuhan ikan patin dalam rangka memenuhi permintaan pasar salah satunya yaitu menggunakan probiotik ke dalam pakan ikan. tujuan dari penelitian ini adalah untuk mengetahui pengaruh penambahan probiotik komersil berbeda pada pakan terhadap pertumbuhan benih ikan patin (pangasius sp). seratus dua puluh ekor benih ikan patin ukuran 5-7 cm digunakan dalam penelitian dengan masa pemeliharaan 8 minggu. benih ikan tersebut dibagi dalam 12 aquarium berukuran 30 x 30 x 30 cm dengan padat penebaran masing-masing 10 ekor. metode penelitian yang digunakan adalah metode eksperimental menggunakan rancangan acak lengkap (ral) yang terdiri empat perlakuan dan tiga kali ulangan. empat perlakuan dilakukan yaitu: p 1 (tanpa penambahan probiotik pada pakan komersil/kontrol), p2 (penambahan probiotik a), p3 (penambahan probiotik b), dan p4 (penambahan probiotik c) pada pakan sebesar 15ml/kg pakan. pakan diberikan secara at satiation sebanyak 5% dari berat tubuh dengan frekuensi tiga kali sehari. sampling dilakukan pada awal penelitian dan setiap minggu sekali. hasil penelitian menunjukkan pertambahan berat dan laju pertumbuhan/growth rate (gr) tertinggi pada p3 dengan jenis probiotik b yakni 6,12 ± 0,56 gram dan 0,15 ± 0,012 g/hari. hasil analisis variansi menunjukkan bahwa penambahan probiotik pada pellet memberikan pengaruh nyata terhadap rata-rata pertambahan berat dan laju pertumbuhan benih ikan patin. kata kunci: pangasius sp., probiotik, pakan, growth rate (gr)

Catfish (pangasius sp.) is the freshwater fish commodity which has high economic value. therefore, increasing catfish growth rate in aquaculture is necessary in the effort to meet market demand. additioning probiotic into fish food ingredient is one of the alternatives to induce growth rate. the aim of this research is to determine the effects of different commercial probiotics, added to the food ingredient, to the growth rate of catfish (pangasius sp.) juveniles. in this research, 120 catfish juveniles under 5 to 7 cm of size range were raised for eight weeks period. the juveniles were raised separately into 12 tanks which had the size of 30 x 30 x 30 cm. the density for each tank was ten juveniles. the research was experimental and conducted by applying randomized complete block design, which had four treatments and three repetition. the four treatments as follows; p1 (without probiotic addition/control), p2 (addition of probiotic a), p3 (addition of probiotic b), and p4 (addition of probiotic c). the amount of probiotic addition was 15 ml/kg of food. the food was served as at satiation with the amount of 5 % of body weight, three times daily. sampling was conducted at the beginning of experiment and every week. the result shows that the highest weight gain and growth rate was provided by treatment p3 with probiotic type a, which are 6,12 + 0,56 g and 0,15 + 0,012 g/day. variance analysis shows that the addition of probiotic to pellet significantly affects to the means of weight gain and growth rate of catfish juvenile. keywords: pangasius sp., probiotic, feed, growth rate (gr)