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

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.

Changes in viable bacterial counts and physicochemical parameters of water used during live transportation of Pangasius catfish (Pangasianodon hypophthalmus) in Bangladesh.

Objective: The study was undertaken to assess the changes in viable bacterial counts and physicochemical parameters of water used during the live transportation of Pangasius catfish (Pangasianodon hypophthalmus). The correlations between the changing patterns of these parameters were also established. Materials and Methods: Water samples were collected every 2 h interval, plated onto agar plates for assesing viable bacterial counts. Physicochemical parameters, namely, water temperature, dissolved oxygen (DO), pH, and ammonia (NH3) concentration in the water were measured with a glass thermometer, DO test kit, pH test kit, and total NH3 measurement kit, respectively. Results: The viable bacterial counts increased significantly from 0 to 2 h in all the studied channels and remained almost similar up to the end of the supply channels. The water temperature was almost stable regardless of the supply channels and transportation period at around 30°C. The DO concentration and pH level decreased, and NH3 concentrations increased gradually in all the supply channels. The viable bacterial counts were inversely correlated to the DO levels and directly associated with the NH3 concentrations of the water used during the live transportation of Pangasius catfish. Conclusions: Gradual increase in viable bacterial counts and fluctuation in some vital physicochemical parameters with the duration of transportation indicated an unfavorable environment for the survival of Pangasius catfish.