Effect of combined use ofBacillusand molasses on microbial communities in shrimp cultural enclosure systems

Abstract

To assess the effect of addition of probiotics and carbon source on the microbial community structure within the shrimp culture, an enclosure system simulating a high density, intensive aquaculture of Litopenaeus vannamei was set up in Dianbai, Maoming, Guangdong province, China. The phylogenetic profiles of microbial communities in the enclosure system after addition of Bacillus and molasses were studied in the middle and final culture season (on the 45th, 75th and 95th day) using polymerase chain reaction-denaturing gradient gel electrophoresis. A total of four groups, each containing a triplicate were set up: Group A (control), Group B (64% of daily feed was provided as molasses with Bacillus sp.), Group C (50% of daily feed amount provided as molasses with Bacillus sp.) and Group D (64% of daily feed amount as molasses alone). The results showed that a-Proteobacteria, d-Proteobacteria, Bacteroidetes and Actinobacteria were the dominant bacteria. Moreover, the relative proportion of a-Proteobacteria increased and that of Bacteroidetes decreased gradually with time. Pathogenic Flexibacter was the dominant genus in Group A on the 45th day, while the functional strains (Sphingomonas sp., Erythrobacter sp., Roseobacter sp., and Rhodobacter sp.) were detected multiple times in Groups B and C. Bacillus sp. was the cultivable, dominant bacterium in Groups B and C on the 95th day. Therefore, the combined use of Bacillus and molasses helped increase diversity of the microbial community, effectively inhibit pathogens, and promote the formation and development of a beneficial microbial community structure in the high density, intensive aquaculture of L. vannamei.

The effects of water additive Bacillus cereus and Pediococcus acidilactici on water quality, growth performances, economic benefits, immunohematology and bacterial flora of whiteleg shrimp (Penaeus vannamei Boone, 1931) reared in earthen ponds

“…Specially, some studies investigated the effect of adding Bacillus spp. to the water in the earthen pond on growth performance and shrimp production (Wang, Xu, & Xia, ), nitrite removal (Song, An, Fu, & Yang, ; Wu et al, ) and microbial community (Hu et al, ). Also, some studies have reported the positive effects of Pediococcus spp.…”

The dynamics of bacterial community in a polyculture aquaculture system of Penaeus chinensis , Rhopilema esculenta and Sinonovacula constricta

“…Furthermore, bacterial communities in gut flora and rearing water associated with L. vannamei larvae at different healthy statuses have been examined (Zheng et al, ). In addition, functional microorganisms, such as probiotics, impact on the disease and growth of shrimp were also frequently reported (Hu et al, ; Lukwambe et al, ). By contrast, researches focused on the bacterial community associated with jellyfish and razor clam were very little.…”

Effects of microbial products and extra carbon on water quality and bacterial community in a fish polyculture system

“…Generally, three ways are used for microbial manipulation, including (a) supplementation of exogenous bacteria (Liang et al., ; Wu et al., ; Zhang et al., ), (b) adding the nutrients that benefit growth of the preferred bacteria (Avnimelech, ; Gao, Shan, Zhang, Bao & Ma, ; Xu, Morris & Samocha, ; Yu et al., ; Zheng, Zhang, Qin & Wang, ) and (c) adding exogenous bacteria and nutrients in combination (Hu et al., ). The outcomes of exogenous bacteria in improving production performance and water quality of aquaculture practices are inconsistent.…”