Seleção de bactérias com potencial probiótico para o cultivo de peixes marinhos

• Ano de defesa: 2021
• Autor(a) principal: Souza, Raoni Gonçalves de
• Orientador(a): Signor, Altevir
• Banca de defesa: Feiden, Aldi , Cardoso, Leonardo Demier
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Estadual do Oeste do Paraná; Toledo
• Programa de Pós-Graduação: Programa de Pós-Graduação em Recursos Pesqueiros e Engenharia de Pesca
• Departamento: Centro de Engenharias e Ciências Exatas
• País: Brasil
• Palavras-chave em Português: Antimicrobiano; Bactérias benéficas; Robalo-peva
• Palavras-chave em Inglês: Antimicrobial; Beneficial bacteria; Fat snook
• Área do conhecimento CNPq: CIENCIAS AGRARIAS::RECURSOS PESQUEIROS E ENGENHARIA DE PESCA
• Link de acesso: https://tede.unioeste.br/handle/tede/8118

The objective of this work was to evaluate, in two studies, the probiotic potential of substances from the marine environment and the intestine of Rachycentron canadum and Macrobrachium rosenbergi and to verify their colonization capacity in the intestinal tract of fat snook (Centropomus parallelus). Study I used 225 juvenile fat snook (3.08 ± 1 g and 77.7 ± 7.12 mm), distributed in 15 100 L tanks fed twice a day at 5% of the total biomass, divided into 3 treatments: multistrain developed (PRO) probiotic (B21CO, B21C, MG, MGO, MB and MBO); positive control (C +) with commercial probiotic; and negative control (C-) placebo group, for a period of 65 days. The antimicrobial activity antagonistic to the pathogen Vibrio parahaemolyticus was positive, the bacterial strains MBO, MB, B21C and B21CO had the best inhibitory halos. All strains were resistant to acid pH and bile salts, being able to survive the digestive process until reaching the animal's intestinal tract. All strains were able to self-aggregate, with MG and MGO being the best aggregation results. Total bacteria and Vibrio spp. in the intestine and in the culture water and in both results there are no statistical differences (p<0.05). Study II consisted of 72 juvenile fat snook (15.47 ± 6.59 g and 100.76 ± 10.40 mm), distributed in 12 100 L tanks (6 fish / tank) and divided into 4 treatments: Control (placebo), MBO (Enterobacter hormaechei), B21CO (Bacillus subtilis) and MBO + B21CO (E. hormaechei + B. subtilis) for a period of 28 days. The quantification of probiotics in the intestine and in the culture water were higher in T1 (first collection, on the 14th day of culture) than in T2 (final collection, on the 28th day of culture) after pathogen inoculation. Vibrio spp. both in the intestine and in the culture water of the treatments with probiotics were studied (p<0.05) smaller compared to the control group. It is concluded that E. hormaechei and B. subtilis strains have great potential without in vitro antagonism against V. parahaemolyticus. All strains analyzed survive according to the conditions of the gastrointestinal tract, as E. hormaechei and B. subtilis strains colonized the intestine of fat snook (C. parallelus) in 14 days, and the S. marcense strain in 21 days. All strains with effective ability to self-aggregate. In vivo tests such as B. subtilis and E. hormaechei strains were able to reduce the benefits of Vibrio spp. without intestine and in the growing water.