Probiotic Supplementation Influences the Diversity of the Intestinal Microbiota During Early Stages of Farmed Senegalese Sole (Solea senegalensis, Kaup 1858)

Abstract

Ingestion of bacteria at early stages results in establishment of a primary intestinal microbiota which likely undergoes several stages along fish life. The role of this intestinal microbiota regulating body functions is crucial for larval development. Probiotics have been proved to modulate this microbiota and exert antagonistic effects against fish pathogens. In the present study, we aimed to determine bacterial diversity along different developmental stages of farmed Senegalese sole (Solea senegalensis) after feeding probiotic (Shewanella putrefaciens Pdp11) supplemented diet for a short period (10-30 days after hatching, DAH). Intestinal lumen contents of sole larvae fed control and probiotic diets were collected at 23, 56, 87, and 119 DAH and DNA was amplified using 16S rDNA bacterial domain-specific primers. Amplicons obtained were separated by denaturing gradient gel electrophoresis (DGGE), cloned, and resulting sequences compared to sequences in GenBank. Results suggest that Shewanella putrefaciens Pdp11 induces a modulation of the dominant bacterial taxa of the intestinal microbiota from 23 DAH. DGGE patterns of larvae fed the probiotic diet showed a core of bands related to Lactobacillus helveticus, Pseudomonas acephalitica, Vibrio parahaemolyticus, and Shewanella genus, together with increased Vibrio genus presence. In addition, decreased number of clones related to Photobacterium damselae subsp piscicida at 23 and 56 DAH was observed in probiotic-fed larvae. A band corresponding to Shewanella putrefaciens Pdp11 was sequenced as predominant from 23 to 119 DAH samples, confirming the colonization by the probiotics. Microbiota modulation obtained via probiotics addition emerges as an effective tool to improve Solea senegalensis larviculture.

Modulation of immunity and gut microbiota after dietary administration of alginate encapsulated Shewanella putrefaciens Pdp11 to gilthead seabream (Sparus aurata L.)

“…The reduction of predominant bands corresponding to this phylogenetic group detected in this study, contrasts with the results obtained in a study carried out by Tapia et al [43] applying SpPdp11 to Senegalese sole juveniles for 30 days, in which the percentage of predominant bands corresponding to g-Proteobacteria was very similar to that observed in control specimens. Tapia-Paniagua et al [43] also observed the ability of the probiotic treatment to reduce the numbers of clones related to Vibrio genus, and it is in accordance to the absence of predominant bands related with this genus detected in this study in gilthead seabream specimens receiving the treatment with SpPdp11.…”

“…The capability of different Lactobacillus species to increase the immunological response has also been reported in fish such as sea bass [67] and gilthead seabream [70]. In addition, specimens of Senegalese sole farmed under high stocking density and receiving a diet supplemented with SpPdp11 showed a higher resistance to disease in comparison with fish fed the diet without the probiotic [67], and this higher resistance was related to important changes in the intestinal microbiota, such as the presence of L. fermentum only in fish fed the diet supplemented with the probiotic [43]. Strains of L. crispatus have been associated with the ability to exert competitive exclusion and antimicrobial against vaginal human pathogens [69e71], being proposed as potential vaginal probiotic [72].…”

“…On the other hand, the absence of these bands in fish fed with control diet may not exclude the presence of LAB in the samples, since they could be below the detection limit of the DGGE technique [66]. Previously, Tapia-Paniagua et al [43,67] demonstrated that the administration of SpPdp11 to farmed Senegalese sole promoted the presence of predominant DGGE bands related to Lactobacillus helveticus and L. fermentum. In our study bands related to L. fermentum and L. jensenii were sequenced from DGGE patterns of fish fed the probiotic diet.…”

“…Although probiotics are of a major potential therapeutic interest, their efficacy is usually limited by poor bioavailability of viable microorganisms on site. However, the ability to colonize the intestine by SpPdp11 of farmed fish such as Senegalese sole has been reported [43,44]. Calcium alginate beads were selected for the present study since calcium alginate is recognized as a simple, inexpensive, and non-toxic method for using when thinking in the food and pharmaceutical industries application [45].…”

Dietary administration of the probiotic SpPdp11: Effects on the intestinal microbiota and immune-related gene expression of farmed Solea senegalensis treated with oxytetracycline

“…Some authors have reported mucine binding proteins and the antimicrobial activity of Lactobacillus fermentum [56][57][58]. In addition, the Shewanella genus has been demonstrated to reduce the presence of Vibrio in the intestinal microbiota of S. senegalensis [59]. Finally, bands related to Firmicutes, Mollicutes and other bacterial groups were only detected in OTC + SpPdp11 fish.…”