Fish growth and immune status can be improved by using encapsulation. Various microcapsules have been used in aquaculture to effectively utilize probiotics to achieve desired fish and shellfish production. Thus , to explore the efficacy of encapsulation, a feeding trial was planned to check the in vivo efficiency of G. candidum encapsulated with alginate (Alg ) alone and in combination with starch (Alg-S) and xanthan (Alg-X) , followed by simple chitosan coating (Alg -C, Alg -S-C, Alg -X-C) and nano-chitosan coating (Alg -CN, Alg -S-CN, Alg -X-CN). Labeo rohita (15.63±0.35 g) fingerlings were evenly distributed in ten different groups. Control group was fed with basal feed while experimental group was given un-encapsulated probiotic, G. candidum @1×10 9 CFU per g, while remaining groups were given probiotic microcapsules based diet containing Alg , Alg -S, Alg-X, Alg -C, Alg -S-C, Alg -X-C, Alg -CN, Alg -S-CN and Alg-X-CN.
Results showed significant impact of probiotic microcapsules on growth , intestinal and serum enzyme activities, h ematology, lipid profile: total cholesterol, high- to low-density lipoprotein and triglyceride value of fish as compared to fish fed control diet. Additionally , chitosan coated G. candidum microcapsules indicated improved performance as compared to fish fed uncoated-microcapsules based diet. Furthermore, among chitosan coated microcapsules, Alg-CN microcapsules showed highest efficiency for all growth and immunity parameters followed by Alg-C microcapsules. It was also revealed that alginate-nano chitosan microcapsule formulation is best to improve bioavailability and target release of locally isolated G. candidum in GI tract of L. rohita . Therefore, this investigation suggests a sustainable alternative for improving the growth and health profile of indigenous carp L. rohita by feeding the diet supplemented with alginate and nano-chitosan coated microcapsules of G. candidum .