Effect of microencapsulation of Pediococus acidilactici on growth performance, body composition and the bacterial flora of rainbow trout (Oncorhynchus mykiss)

Document Type : Research Paper


1 Department of Aquaculture, Faculty of Natural Resources and Marine Sciences, Tarbiat Modares University, Noor, Mazandaran, Iran

2 Department of Food Hygiene, Faculty of Veterinary Medicine, University of Tehran, Tehran, Tehran, Iran

3 Department of Fisheries and Environmental Sciences, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Golestan, Iran


The present study was conducted to evaluate the effect of probiotic bacteria Pediocucus acidilactici encapsulated with alginate and resistant starch (Hi maize) coated by chitosan, on growth indices, intestinal flora and carcass composition of rainbow trout (Oncorhynchus mykiss). Rainbow trout fingerling with an average weight of 18.41 ± 0.32 g were fed with diets including: encapsulated probiotic, free probiotic, diet containing capsules free of bacteria (positive control) and control diet containing no probiotics for 60 days. The results exhibited that there were no significant differences in growth rate, weight gain, specific growth rate and feed conversion ratio in different groups. The highest number of lactic acid bacteria was found in the fish received the encapsulated bacteria while the lowest was in the control group (p<0.05). Maximum carcass protein and fat contents were observed in encapsulated bacteria treatment and maximum carcass ash was in control group (p<0.05). Totally, the results suggest that encapsulated P. acidilactici improves the growth performance, body composition and bacterial flora of rainbow trout.