Effect of Lactobacillus plantarum nano-microencapsulated with alginate/chitosan on growth performance, nutritional indices and Blood parameters in rainbow trout (Oncorhynchus mykiss)

The present study was designed to compare the effect of Lactobacillus plantarum nano/microencapsulation with alginat/chitosan and only probiotic (none encapsulation) on growth performance, nutritional indices and blood parameters on rainbow trout (Oncorhynchus mykiss). 480 fry rainbow trout with 15±1.2 g in weight were sorted and fed for eight weeks in four groups (with three replicates) including: Lactobacillus plantarum without any encapsulation (T1), encapsulated Lactobacillus plantarum with Alginate/ Chitosan (T2), alginate/ chitosan enriched free bacteria (T3) and basic diet (control group), respectinely. Results showed the best specific growth rate and Condition Factor were seen in treatment 2 and Also feed conversion ratio and protein efficiency ratio improved in treatments 2 and 3 in contrast with control group, although this increase was not significant. Study of Blood parameters showed higher hematocrit, hemoglobin and mean corpuscular volume were seen in treatment 2 which hematocrit was significantly different from control treatment (p˂0.05). The highest red blood cells, means corpuscular hemoglobin concentration and lowest means corpuscular hemoglobin were seen in treatment1. The number of white blood cells was significantly increased in treatment3 than control group (p˂0.05). Therefore, based on obtained results, it can be concluded that use of probiotic Lactobacillus plantarum could improve growth performance, nutritional indices and blood parameters, but this technology recommend for use probiotic on rainbow trout required further studies on the application.