Kinerja Pertumbuhan, Respons Imun, dan Resistansi Ikan Nila yang Diberi Paraprobiotik Bacillus sp. NP5 dan Diinfeksi Streptococcus agalactiae

Abstract

Penelitian ini bertujuan untuk mengevaluasi efektivitas pemberian paraprobiotik Bacillus sp. NP5 yang ditambahkan melalui pakan pada kinerja pertumbuhan, respons imun, dan resistansi ikan nila terhadap infeksi Streptococcus agalactiae. Penelitian ini menggunakan rancangan acak rengkap yang terdiri dari 3 perlakuan 5 ulangan, penambahan probiotik 1%, penambahan paraprobiotik 1% dan tanpa penambahan probiotik atau paraprobiotik (kontrol). Ikan perlakuan dipelihara selama 30 hari, pada hari ke 31, uji tantang dengan S. agalactiae (107 CFU ml-1) yang diinjeksikan melalui intraperitoneal kecuali perlakuan kontrol negatif yang diinjeksi dengan PBS. Hasil penelitian setelah 30 hari pemberian probiotik dan paraprobiotik Bacillus sp. NP5 menunjukkan kinerja pertumbuhan dan respons imun yang meningkat signifikan (P<0.05) dibandingkan dengan kontrol. Pasca uji tantang, peningkatan respons imun pada perlakuan probiotik dan paraprobiotik Bacillus sp. NP5 menunjukkan tingkat kelangsungan hidup yang lebih tinggi (P<0.05) dibandingkan kontrol positif pasca uji tantang dengan S. agalactiae. Pemberian probiotik dan paraprobiotik Bacillus sp. NP5 melalui pakan efektif dalam meningkatkan kinerja pertumbuhan, respons imun, dan resistansi ikan nila terhadap infeksi Streptococcus agalactiae.

The aim of this study was to evaluate the effectiveness of paraprobiotic Bacillus sp. NP5 administration through commercial feed on the growth performances, immune responses, and resistance of nile tilapia against Streptococcus agalactiae infection. This study used a completely randomized design, which consisted of three treatments with five repetitions, that were 1% (v/w) addition of probiotic, 1% (v/w) addition of paraprobiotic, and no addition of probiotic or paraprobiotic (control). The experimental fish were reared for 30 days and on day 31, the fish was challenge tested with S. agalactiae (107 CFU ml-1) injected by intraperitoneal route, unless the negative control was injected with PBS. The results of this study showed significantly improved growth performances and immune responses (P<0.05), compared to the control group after 30 days of probiotic and paraprobiotic Bacillus sp. NP5 administered. After challenge tested, the increased of immune responses in the probiotic and paraprobiotic of Bacillus sp. NP5 showed a higher survival rate (P<0.05), than positive control after callenge tested with S. agalactiae. Administration of probiotic and paraprobiotic Bacillus sp. NP5 through the commercial feed were effective in increase the growth performances, immune responses, and resistance of nile tilapia against S. agalactiae infection.