Dietary supplementation effects of Pediococcus acidilactici as probiotic on growth performance, digestive enzyme activities and immunity response in zebrafish

چکیده مقاله

This study was carried out to assess the effects of Pediococcus acidilactici on zebrafish (Danio rerio). Different levels of P. acidilactici including 0, 1 × 10⁶, 2 × 10⁶, 4 × 10⁶ and 8 × 10⁶ colony‐forming unit per g of the diet (cfug⁻¹) were examined in fish with 120 ± 10 mg weight for 60 days in a completely randomized design. The results showed that the best growth indices were recorded in group 4 × 10⁶ cfug⁻¹ (p < 0.05). The highest number of total viable count and lactic acid bacteria of intestine were found in group 4 × 10⁶ cfug⁻¹ (p < 0.05). The maximum activity of digestive enzymes including amylase, lipase, protease and alkaline phosphatase was observed in group 4 × 10⁶ cfug⁻¹. The highest activity for superoxide dismutase was recorded in group 4 × 10⁶ cfug⁻¹ while catalase, glutathione peroxidase and glutathione reductase showed the highest activity in group 8 × 10⁶ cfug⁻¹. The most growth inhibition zone of Aeromonas hydrophylla,Flavobacterium columnare, Vibrio anguillarum and Edwardsiella tarda was found in group 4 × 10⁶ cfug^‐1 (p < 0.05). Therefore, P. acidilactici as a probiotic improved growth and immunity of the zebrafish and could be used by zebrafish farmers.