Multi-species probiotics improve growth, intestinal microbiota and morphology of Indian major carp mrigal Cirrhinus cirrhosus

Abstract

This study aimed to examine the effects of multi-species probiotic on growth, hematological status, intestinal microbes, and intestinal morphology of mrigal (Cirrhinus cirrhosus). The mrigal fries (average weight 0.51 g) were reared for 60 days by supplementing multi-species probiotics containing Bacillus spp. (1 × 10⁹ cfu/mL) and Lactobacillus spp. (1 × 10¹¹ cfu/mL) in the raising water at doses of 0 (control), 0.5, and 1.0 mL/L. The results indicated that fish reared with multi-species probiotics showed significantly higher growth performance and feed efficiency where the survival rate was similar in all cases. Accordingly, significant higher red blood cell (RBC) and white blood cell (WBC) were counted from the fish reared with multi-species probiotic. There was a considerable difference in bacterial microbiota between the experimental and control group. Multi-species probiotics significantly enhanced the length, width, and villus area. Several immune response indicators like fattening of intestinal mucosal fold, width of lamina propria, the width of enterocytes, and abundance of goblet cells were also increased significantly in fish that received multi-species probiotics. This study revealed that multi-species probiotics can significantly contribute to the growth of mrigal through upgrading intestinal microbiota and morphology, which can be suggested as an eco-friendly growth stimulator in mrigal farming.

Keywords: Aquaculture; Bacillus Spp.; Gut health; Hematology; Lactobacillus spp..

Fig. 1

Histological alteration of the intestine of Indian major carp mrigal (Cirrhinus cirrhosus) reared with multi-species probiotics for 60 days; (a) control (0 mL/L), (b) low dose (0.5 mL/L), (c, d) high dose (1.0 mL/L); VW; villus width, VL; villus length, VA; villus area, TW; thickness of wall, TM; thickness of muscular, and CD; Crypt depth. Scale bar = 100 µm.

Fig. 2

Immune response indicators (a-d) of histological gut of Indian major carp mrigal (Cirrhinus cirrhosus) reared with multi-species probiotics for 60 days; MF; mucosal folds, LP; lamina propria, GC; goblet cell and EC; enterocyte. Scale bar = 400 µm.