Improvement in the growth performance of white shrimp,Litopenaeus vannamei, by a protease-producing probiotic,Bacillus subtilisE20, from natto

Abstract

Aims: To isolate and identify a benefic bacterium, Bacillus subtilis E20, from natto (fermented soybeans), and incorporate it into shrimp feed to promote shrimp growth performance. Methods and Results: A protease-producing bacterium, E20, isolated from natto was identified as B. subtilis by an API 50 CHB kit and the 16S rDNA sequence. B. subtilis E20 was able to grow at a broad range of temperatures (10-50°C), pH values (5-10), and NaCl levels (0-9%). The best culture conditions for B. subtilis E20 to produce the protease were 40°C, a pH of 6-8 and 0% NaCl. No shrimp died after being injected with B. subtilis E20 [up to 10 9 colony-forming units (CFU) per shrimp]. Bacillus subtilis E20 was incorporated in diets at the levels of 0 (control), 10 6 , 10 7 , and 10 8 CFU kg )1 for shrimp grow-out culture, and results showed that after feeding on B. subtilis E20-containing diets (10 8 CFU kg )1 of diet), shrimp had excellent growth performance and production compared to the control because protease activities in the digestive tract were improved by B. subtilis E20. Conclusions: Bacillus subtilis E20 isolated from natto is a great protease producer and is able to improve shrimp growth performance through increasing the digestibility of food. Significance and Impact of the Study: Results suggest that B. subtilis E20 is a potential candidate for use as a probiotic to improve shrimp growth performance, and consequently reduce feed costs.

Evaluation of different probiotic strains for growth performance and immunomodulation in Pacific white shrimp Penaeus vannamei Boone, 1931

“…Average daily growth (ADG) was high in S. cerevisiae (0.106±0.002 g) and B. subtilis (0.104 ± 0.002 g) followed by other strains such as Sb (0.092 ± 0.002 g), Lc (0.083 ± 0.001 g), Lr (0.082 ± 0.001 g), Ent (0.065 ± 0.004) and Cp (0.064 ± 0.002 g) whereas in control it was observed to be the lowest (0.062 ± 0.004 g). Similar to our findings, several studies have demonstrated the beneficial effects of probiotics on the growth performance in shrimp (Wang et al, 2007;Shen et al, 2010;Liu et al, 2009). …”

Effects of Probiotic Bacillus subtilis on Intestinal Microbial Diversity and Immunity of Orange Spotted Grouper Epinephelus coioides

“…Liu et al (2012) who showed that B. subtilis supplemented diet significantly higher growth than that of grouper fed the control diet after 28 days of feeding.…”

Growth Performance of Catfish (Clarias gariepinus) in Biofloc-Based Super Intensive Culture Added with Bacillus sp.

“…Energy difference resulting from this process can be used for the growth. Liu et al (2009) mentioned that the increasing growth rate of aquatic organisms provided with probiotic in their feed was related to higher enzymatic digestion activity together with vitamin synthesis, therefore, digestibility and organism weight were also increased.…”