effects of feeding adult artemia enriched with synbiotic on growth indices, intestinal microbiota and stress resistance of angel fish (pterophyllum scalare)

during the recent years, there has been an increasing interest toward dietary administration of synbiotic to improve growth, immunity and physiology of fish. the aim of this study was to evaluate the effects of feeding on synbiotic (pediococcus acidilactici and fructooligosaccharide) enriched adult artemia franciscana on growth indices, intestinal microbiota and stress resistance of angel fish (pterophyllum scalare) juvenile. three hundred and sixty fish with initial weight of 3.2 ± 0.13 g were randomly divided into 12 aquaria (50 l) assigned to four groups with three raplicates. fish were fed for 48 days with dietary treatments, including treatment 1: feeding adult artemia without enrichment (control group), treatment 2: feeding adult artemia enriched with probiotics p. acidilactici (700 mg), 3: feeding adult artemia enriched with prebiotics fructooligosaccharide (100 mg), group 4: feeding adult artemia enriched with a synbiotic (700 mg p. acidilactici and 100 mg prebiotics fructooligosaccharide). growth indices, intestinal microbiota as well as resistance of fish against environmental stress (acute increase of temperature and salinity) were measured. artemia enriched with synbiotic significantly improved the growth performance compared to other treatments (p < 0.05). the highest body weight gain and specific growth rate (sgr) was observed in synbiotic fed fish (p < 0.05). compared to the other treatments, the population of lactic acid bacteria was significantly higher in the intestinal microbiota of fish fed artemia enriched with synbiotic (p < 0.05). in the environmental stress challenge, the maximum resistance to abrupt decrease of temperature (17 ° c) or elevation of salinity (12 g per liter) was found in the synbiotic treatment. these results revealed that enriching artemia with the synbiotic showed better result compared singular enrichment with probiotics or prebiotics.