Application of synbiotic with different probiotic doses to prevent vibriosis in humpback grouper

Abstract

ABSTRACT The aim of this study was to evaluate the supplementation of synbiotic with different doses of probiotics to prevent vibriosis in humpback grouper ( Cromileptes altivelis). Grouper (3.0±0.48 g) fed by control feeds (without supplementation of synbiotic) which were K(-) and K(+), treatment feeds with supplementation of synbiotic with different doses of probiotic (probiotic 10 4 cfu/mL) 1% + prebiotic 2% (P1) v/w, (probiotic 10 6 cfu/mL) 1% + prebiotic 2% (P2) v/w, (probiotic 10 8 cfu/mL)1% + prebiotic 2% (P3) v/w) for 30 days. After a feeding trial period, there were observation of the bacterial counts in the fish intestine, the fish growth performance and immune response. Then all the grouper were challenged by Vibrio alginolyticus, except K (-). This study showed that survival, daily growth and food conversion ratio (FCR) of grouper in treatment P2 ((probiotic 10 6 cfu/mL) 1% + prebiotic 2%) and P3 (probiotic (10 8 cfu/mL) 1% + prebiotic 2%) were significantly better (P>0.05) than controls. The different doses of probiotic in synbiotic (probiotic 10 4 cfu/mL, probiotic 10 6 cfu/mL and probiotic 10 8 cfu/mL) provided better immune response than controls. Keywords: synbiotic, Vibrio alginolyticus, Bacillus sp., Cromileptes altivelis ABSTRAK Tujuan penelitian ini adalah mengkaji pemberian sinbiotik dengan dosis probiotik berbeda untuk mencegah penyakit vibriosis pada ikan kerapu bebek ( Cromileptes altivelis). Ikan kerapu dengan berat (3,0±0,48 g) diberikan pakan kontrol (tanpa penambahan sinbiotik) K(-) dan K(+), pakan perlakuan dengan penambahan sinbiotik dengan dosis probiotik berbeda: probiotik ((10 4 cfu/mL) 1% + prebiotik 2%) v/w (P1), ((probiotik 10 6 cfu/mL) 1% + prebiotik 2%) v/w (P2), dan ((probiotik 10 8 cfu/mL)1% + prebiotik 2%) v/w (P3) selama 30 hari. Setelah perlakuan pakan sinbiotik, dilakukan pengamatan terhadap jumlah total bakteri di usus, kinerja pertumbuhan dan respons imun. Kemudian ikan kerapu pada seluruh perlakuan, kecuali kontrol negatif (-) diberi uji tantang dengan Vibrio alginolyticus. Hasil penelitian menunjukkan bahwa sintasan, laju pertumbuhan harian (LPH), dan rasio konversi pakan (FCR) pada perlakuan P2 ((probiotik 10 6 cfu/mL) 1% + prebiotik 2%) dan  P3 (probiotik (10 8 cfu/mL) 1% + prebiotik 2%) secara signifikan lebih baik (P<0,05) bila dibandingkan dengan kontrol. Perlakuan sinbiotik dengan dosis probiotik berbeda (probiotik 10 4 cfu/mL, probiotik 10 6 cfu/mL, dan probiotik 10 8 cfu/mL) juga memberikan respons imun yang lebih baik dibandingkan dengan kontrol. Kata kunci : sinbiotik, Vibrio alginolyticus, Bacillus sp., Cromileptes altivelis