The use of immunostimulant from phycocyanin of Spirulina platensis to control motile aeromonad septicaemia (MAS) disease in common carp Cyprinus carpio

                                                                  ABSTRAK         Motile aeromonad septicaemia (MAS) adalah penyakit yang sering menyerang ikan mas Cyprinus carpio yang disebabkan oleh bakteri Aeromonas hydrophila. Penelitian ini bertujuan untuk menguji kinerja imunostimulan fikosianin dari Spirulina platensis dalam mengatasi penyakit MAS pada ikan mas. Penelitian ini terdiri atas dua tahap, pertama, pakan ikan dengan penambahan fikosianin 150 mg/kg, 250 mg/kg, dan 350 mg/kg pakan serta kontrol tanpa penambahan fikosianin. Setelah 14 hari, ikan diuji tantang dengan A.hydrophila. Tahap kedua, dosis terbaik dari penelitian pertama digunakan untuk pakan ikan masing-masing selama satu minggu/bulan, dua minggu/bulan, tiga minggu/bulan, dan dua minggu/bulan dengan interval satu minggu. Setelah 28 hari, ikan diuji tantang dengan A. hydrophila. Hasil penelitian pertama menunjukkan bahwa kelangsungan hidup relatif (RPS) ikan yang diberi pakan fikosianin 150 mg/kg, 250 mg/kg, dan 350 mg/kg pakan adalah 87,50%; 81,25%; dan 75,00%. Total eritrosit, hemoglobin, total leukosit, aktivitas fagositik, dan respiratory burst menunjukkan hasil yang lebih tinggi daripada kontrol untuk semua perlakuan pemberian fikosianin. Penelitian kedua menunjukkan bahwa nilai RPS ikan diberi pakan selama satu minggu/bulan, dua minggu/bulan, tiga minggu/bulan, dan dua minggu/bulan dengan interval satu minggu yaitu 65,38%; 69,23%; 76,92%; dan 69,23%. Respons imun ikan yang diberi fikosianin lebih tinggi daripada kontrol serta mampu menekan jumlah bakteri A. hydrophila di hati, ginjal, dan usus. Kesimpulan dari penelitian ini bahwa pemberian fikosianin sebanyak 150 mg/kg pakan selama tiga minggu/bulan memiliki nilai RPS tertinggi. Kata kunci: fikosianin, Spirulina platensis, Aeromonas hydrophila, Cyprinus carpio  ABSTRACT Motile aeromonad septicaemia (MAS) is a major disease in common carp Cyprinus carpio caused by Aeromonas hydrophila. This study aimed to evaluate the performance of phycocyanin imunostimulant extracted from Spirulina platensis to control MAS disease in common carp. This study was conducted into two phases. First phase was conducted by adding 150 mg/kg, 250 mg/kg, 350 mg/kg feed phycocyanin dose, and 0 mg/kg feed phycocyanin dose as control treatment. Fish was challenged with pathogenic A.hydrophila after 14 days rearing. Second phase was conducted by applying the best dose obtained from the first phase added in the feed for feeding the fish in one week/month, two weeks/month, three weeks /month, and two weeks/month with one week interval. Fish was challenged with pathogenic A.hydrophila after 28 days rearing. First phase study result showed that the relative percent survival (RPS) for fish fed 150 mg/kg, 250 mg/kg, and 350 mg/kg phycocyanin dose were 87.50%, 81.25%, and 75.00% respectively. Total erythrocytes, hemoglobin, total leucocytes, phagocytic activity, and respiratory burst showed higher results than control treatment on all treated fish. The second phase study showed that fish fed one week/month, two weeks/month, three weeks/month, and two weeks/month with one week interval had RPS value 65.38%, 69.23%, 76.92%, and 69.23% respectively. The immune responses of treated fish were higher than control treatment, as well as the number of pathogenic A. hydrophila in the liver, kidney, and intestine. Fish fed with phycoyanin dose 150 mg/kg feed and three weeks/month administration had the highest RPS value. Keywords: Phycocyanin, Spirulina platensis, Aeromonas hydrophila, Cyprinus carpio