Application of probiotic bacteria isolated from catfish (Clarias batrachus) intestine to enhance growth performance and resistance of carp (Cyprinus carpio) against Aeromonas hydrophila

Abstract

The objective of research was to isolate probiotic bacteria from catfish intestine and to examine its effects on the growth and resistance of carp against Aeromonas hydrophila. The probiotic isolated from intestine was grown on MRS agar.\xa0 Fish used in this research was juvenile of carp with an average weight of 5.5 g obtained from Freshwater Aquaculture Board at Tatelu Village, North Sulawesi Province.\xa0 Before running the experiment, the juveniles were adapted for one weeks in 15 glass aquaria at a density of 15 individuals each.\xa0 After acclimatization, the fish were fed diet supplemented with probiotic at different concentrations namely 1x10 9 , 1x10 8 , 1x10 7 ,\xa0 1x10 6 cfu/mL for three weeks. The fish were fed two times a dayat 08.00 am and 17.00 pm with a dose of 5% of body weight per day. At the end of feeding, the fish were challenged with A. hydrophila.\xa0 Data collected included average growth rate, absolute growth, feed efficiency, and food conversion ratio.\xa0 Research results found that the addition of probiotic into feed was\xa0 able to increase growth and feed efficiency and reduce food conversion ratio as well (p<0.01). The best growth, feed efficiency and food conversion ratio were obtained in fish fed diet added with probiotic bacteria at 1x10 8 cfu/mL.\xa0 The highest survival rate was also observed in fish probiotic diet containing 1x10 8 cfu/mL.\xa0 As conclusion, probiotic bacteria isolated from catfish intestine was potential to improve growth, feed efficiency, reduce food conversion ratio and increase resistance of fish against bacterial pathogen. Keywords: probiotic, carp, Aeromonas hydrophila , feed efficiency, food conversion ratio ABSTRAK Penelitian ini bertujuan untuk mengisolasi bakteri probiotik dari usus ikan lele dan menguji pengaruh pemberian probiotik dari usus ikan lele terhadap pertumbuhan dan resistensi ikan mas terhadap infeksi Aeromonas hydrophilla. Sumber probiotik diisolasi dari usus ikan lele menggunakan media MRS (de Man Rogosa Sharpe) dan bakteri Aeromonas hydrophilla ditumbuhkan pada media TSA (Tryptic Soy Agar). ikan uji diambil dari Balai Budidaya Air Tawar Tatelu , Provinsi Sulawesi Utara . ikan diaklimatisasi selama seminggu dalam 15 akuarium dengan kepadatan 15 ekor/akuarium dan berat awal rata-rata 5,5 g. Setelah diaklimatisasi ikan diberi pakan yang ditambahkan bakteri probiotik sebagai perlakuan dengan konsentrasi berbeda yaitu 1x10 9 , 1x10 8 , 1x10 7 ,\xa0 1x10 6 cfu/mL selama empat minggu sebanyak 5% /berat tubuh/hari dengan frekuensi pemberian pakan dua kali sehari yaitu jam 08.00 pagi dan jam 17.00 sore. Setelah diberi perlakuan maka diuji tantang dengan bakteri Aeromonas hydrophilla. \xa0Data yang dikumpulkan terdiri dari laju pertumbuhan harian, pertumbuhan mutlak, efesiensi pakan, konversi pakan dan uji tantang terhadap bakteri patogen. Hasil penelitian mendapatkan bahwa penambahan bakteri probiotik dalam pakan mampu meningkatkan pertumbuhan, efesiensi pakan dan menurunkan konversi pakan (p<0.01). Pertumbuhan, efesiensi pakan dan konversi pakan yang terbaik dicapai pada ikan yang diberi pakan dengan penambahan bakteri probiotik 1x10 8 cfu/mL.\xa0 Kelangsungan hidup ikan mas yang diuji tantang dengan bakteri patogen yang paling tinggi dicapai pada ikan yang diberi pakan 1x10 8 cfu/mL. Sebagai kesimpulan bahwa bakteri probiotik yang diisolasi dari usus ikan lele berpotensi meningkatkan pertumbuhan, efesiensi pakan, menurunkan konversi pakan serta meningkatkan sistem kekebalan tubuh pada ikan mas. Kata Kunci : Probiotik, Ikan Mas, Aeromonas hydrophilla , Pertumbuhan, Efesiensi Pakan, Konversi Pakan