Penambahan Probiotik Bacillus NP5 dengan Frekuensi Pemberian Berbeda pada Sistem Bioflok terhadap Pertumbuhan dan Kesehatan Benih Ikan Nila

Abstract

Sistem bioflok diketahui mampu meningkatkan kinerja pertumbuhan, respons imun ikan, serta memperbaiki kualitas air. Penelitian ini bertujuan menganalisis pengaruh perbedaan frekuensi penambahan probiotik Bacillus NP5R pada sistem bioflok terhadap kelangsungan hidup, kinerja pertumbuhan dan status kesehatan benih ikan nila (Oreochromis niloticus) terhadap infeksi Aeromonas hydrophila. Metode yang digunakan adalah eksperimental Rancangan Acak Lengkap dengan lima perlakuan dan tiga ulangan, meliputi kontrol positif dan kontrol negatif (tanpa probiotik) serta perlakuan penambahan probiotik frekuensi setiap hari (P1), tiga hari sekali (P3), dan lima hari sekali (P5) dengan kepadatan 105 CFU mL?¹ selama 40 hari sebelum uji tantang. Hasil penelitian menunjukkan bahwa perlakuan P3 memberikan hasil terbaik yang ditunjukkan oleh tingkat kelangsungan hidup pascauji tantang tertinggi (83,30±0,57%), peningkatan pertumbuhan yang signifikan (bobot akhir 1,09±0,03 g, laju pertumbuhan harian 2,43±0,05 g hari?¹), dan rasio konversi pakan terendah (1,05±0,03). Perlakuan P3 juga secara signifikan meningkatkan respons imun melalui peningkatan total eritrosit, leukosit, hemoglobin, dan hematokrit. Penambahan probiotik Bacillus NP5R setiap tiga hari sekali pada pemeliharaan benih ikan nila sistem bioflok terbukti lebih efektif dalam meningkatkan kelangsungan hidup, kinerja pertumbuhan dan status kesehatan benih ikan nila Oreochromis niloticus terhadap infeksi A. hydrophila.

The biofloc system is known to improve fish growth performance, immune responses, and water quality. This study aimed to analyze the effects of different frequencies of Bacillus NP5R probiotic addition in a biofloc system on the survival rate, growth performance, and health status of Nile tilapia (Oreochromis niloticus) fingerlings against Aeromonas hydrophila infection. The method used was an experimental completely randomized design with five treatments and three replications, consisting of a positive control and a negative control (without probiotic), as well as probiotic addition treatments at frequencies of every day (P1), every three days (P3), and every five days (P5) at a density of 105 CFU mL?¹ for 40 days prior to the challenge test. The results showed that the P3 treatment yielded the best outcomes, as indicated by the highest post-challenge survival rate (83.30±0.57%), significant growth improvement (final weight 1.09±0.03 g, daily growth rate of 2.43±0.05 g day?¹), and the lowest feed conversion ratio (1.05±0.03). P3 also significantly enhanced immune responses by optimizing total erythrocytes, leukocytes, hemoglobin, and hematocrit levels. The addition of Bacillus NP5R probiotic every three days during the rearing Nile tilapia fingerlings in a biofloc system proved to be more effective in improving the surviral, growth performance, and health status of Oreochromis niloticus fingerlings against A. hydrophila infection.