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The objective was to evaluate the effect of using prebiotics (Saccharomyces cerevisiae boulardii) or Monensin in the confinement initial phase and replacing monensin with probiotics (Bacillus toyonensis) in the final phase. Forty-eight Nellore steers were used, with an initial mean body weight of 356.2 ± 17.98 kg, distributed in a completely randomized design. Two animals per pen were confined in 80 m2 pens. The experiment was divided into two stages. The first phase lasted from day 1 to the 30th day, during which the animals were divided into two groups of 24 animals each. The treatments were the nutritional additives added to the diet: monensin or prebiotics (Saccharomyces cerevisiae boulardii). In the second phase, each group was subdivided into 12 animals by treatment, which received monensin or probiotics (Bacillus toyonensis). Dry matter intake (DMI), animal performance, and economic evaluation of the use of additives were evaluated. There was no additive effect on DMI, average daily gain, and total weight gain of the animals in the first experimental stage (0-30th day). Likewise, in the second stage (31st-100th day), there was no treatment effect for the variables of intake and performance. There was no effect of the use of different nutritional additives on carcass characteristics. The use of prebiotics sequentially to probiotics promoted gross and net yield that was superior to that of the animals that consumed monensin. Yeasts and bacteria respectively in the first and second phases of confinement can replace monensin in confinement diets.

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The aim of the present study was to obtain an effective vehiculation system in which bacterial agents could maintain viability improving their removal capacity. Herein, we present a novel biohybrid membrane of polymeric nanofibers and free-living bacteria for the simultaneous removal of pollutants. In this system, bacteria are free within the pores between the nanofibers and adsorbed to the surface of the membranes. Association between bacteria and the membranes was performed through a self-formulated medium, and the presence of the bacteria in the polymeric matrix was evidenced through atomic force microscopy (AFM). Biohybrid membranes associated with the remediation agents Bacillus toyonensis SFC 500-1E and Acinetobacter guillouiae SFC 500-1A promoted a reduction of up to 2.5 mg/L of hexavalent chromium and up to 200 mg/L of phenol after 24 h of treatment in synthetic medium containing the contaminants. Similarly, more than 46% of the hexavalent chromium and all of the phenol content were removed after treatment of a tannery effluent with initial concentrations of 7 mg/L of Cr(VI) and 305 mg/L of phenol. Counts of the remediation agents from the membranes were always above 1.107 CFU/g, also in the reutilization assays performed without reinoculation. Biohybrid membranes were hydrolysis-resistant, reusable, and effective in the simultaneous removal of contaminants for more than 5 cycles. Viability of the microorganisms was maintained after long-term storage of the membranes at 4 °C, without the use of microbiological media or the addition of cryoprotectants. Graphical abstract KEY POINTS: • Polymeric membranes were effectively associated with the SFC 500-1 remediation consortium • Biohybrid membranes removed hexavalent chromium and phenol from different matrices • Removal of contaminants was achieved in many successive cycles without reinoculation.

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Bacillus toyonensis is a probiotic microorganism that for decades has been used in animal nutrition around the world. The objective of this work was to evaluate the immunomodulatory effect of oral B. toyonensis supplementation in dogs vaccinated against canine parvovirus. Puppies were randomly selected and divided in two groups, one received B. toyonensis at a concentration of 2x10 8 viable spores per day and another group without supplementation was left as control. The puppies were vaccinated against canine parvovirus type 2. B. toyonensis supplementation was efficient in stimulating specific IgG for parvovirus with titers of 2, 3, and 2.5-fold higher than controls at 7, 21, and 35 pos-vaccination days respectively. Peripheral blood mononuclear cells (PBMCs) from dogs were cultured and stimulated with B. toyonensis DNA, vegetative cell and spores. The mRNA transcription of cytokines IL-4, IL-17, and IFN-γ up modulated by the stimuli. Thus, we conclude in this study that B. toyonensis supplementation may amplify the vaccine immune response against canine parvovirus.(AU)

Bacillus toyonensis é um micro-organismo probiótico que há décadas é utilizado na nutrição animal em todo o mundo. O objetivo deste trabalho foi avaliar o efeito imunomodulador da suplementação oral de B. toyonensis em cães vacinados contra o parvovírus canino. Os filhotes foram selecionados aleatoriamente e divididos em dois grupos, um recebeu B. toyonensis na concentração de 2 × 10 8 esporos viáveis por dia e outro grupo sem suplementação como controle. Os filhotes foram vacinados contra o parvovírus canino tipo 2. A suplementação com B. toyonensis foi eficiente em estimular IgG específica para parvovírus com títulos de 2, 3 e 2,5 vezes maior que os controles aos 7, 21 e 35 dias pós-vacinação, respectivamente. Células mononucleares do sangue periférico (PBMCs) de cães foram cultivadas e estimuladas com DNA de B. toyonensis, células vegetativas e esporos. A transcrição do mRNA das citocinas IL-4, IL-17 e IFN-γ foi modulada pelos estímulos. Assim, concluímos neste estudo que a suplementação com B. toyonensis pode amplificar a resposta imune da vacina contra o parvovírus canino.(AU)

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RESUMO

Bacillus toyonensis is a probiotic microorganism that for decades has been used in animal nutrition around the world. The objective of this work was to evaluate the immunomodulatory effect of oral B. toyonensis supplementation in dogs vaccinated against canine parvovirus. Puppies were randomly selected and divided in two groups, one received B. toyonensis at a concentration of 2x10 8 viable spores per day and another group without supplementation was left as control. The puppies were vaccinated against canine parvovirus type 2. B. toyonensis supplementation was efficient in stimulating specific IgG for parvovirus with titers of 2, 3, and 2.5-fold higher than controls at 7, 21, and 35 pos-vaccination days respectively. Peripheral blood mononuclear cells (PBMCs) from dogs were cultured and stimulated with B. toyonensis DNA, vegetative cell and spores. The mRNA transcription of cytokines IL-4, IL-17, and IFN-γ up modulated by the stimuli. Thus, we conclude in this study that B. toyonensis supplementation may amplify the vaccine immune response against canine parvovirus.(AU)

Bacillus toyonensis é um micro-organismo probiótico que há décadas é utilizado na nutrição animal em todo o mundo. O objetivo deste trabalho foi avaliar o efeito imunomodulador da suplementação oral de B. toyonensis em cães vacinados contra o parvovírus canino. Os filhotes foram selecionados aleatoriamente e divididos em dois grupos, um recebeu B. toyonensis na concentração de 2 × 10 8 esporos viáveis por dia e outro grupo sem suplementação como controle. Os filhotes foram vacinados contra o parvovírus canino tipo 2. A suplementação com B. toyonensis foi eficiente em estimular IgG específica para parvovírus com títulos de 2, 3 e 2,5 vezes maior que os controles aos 7, 21 e 35 dias pós-vacinação, respectivamente. Células mononucleares do sangue periférico (PBMCs) de cães foram cultivadas e estimuladas com DNA de B. toyonensis, células vegetativas e esporos. A transcrição do mRNA das citocinas IL-4, IL-17 e IFN-γ foi modulada pelos estímulos. Assim, concluímos neste estudo que a suplementação com B. toyonensis pode amplificar a resposta imune da vacina contra o parvovírus canino.(AU)

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Bacillus sp. SFC 500-1E is used for the effective treatment of tannery effluents since it consistently removes hexavalent chromium from diverse contaminated matrices. The aim of the present study was to complete identification of the strain through a polyphasic characterization, which included the pattern of carbohydrate utilization, fatty acids profile, multilocus sequence analysis, multiplex PCR profile and the analysis of the complete genome sequence. Morpho-physiological and biochemical characterization results and analysis of 16S rRNA sequences were not conclusive. The strain formed a monophyletic clade with B. toyonensis BCT-7112, B. thuringiensis MC28 and B. cereus Rock 1-3. However, genomic comparisons with type strains of B. cereus and B. thuringiensis showed that the isolated belonged to a different species. Results of this study highlight the relevance of the genome sequence of this strain, identified as Bacillus toyonensis SFC 500-1E, to expand knowledge of its bioremediation potential and to explore unknown decontamination activities.

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Diseases caused by phytopathogenic microorganisms account for enormous losses for agribusiness. Although Bacillus species are recognized as being antimicrobial producers and some may provide benefits to plants, the association between Bacillus toyonensis and plants has not been studied. In this study, the whole-genome sequenced endophytic B. toyonensis BAC3151, which has demonstrated antimicrobial activity and quorum sensing inhibition of phytopathogenic bacteria, was investigated for its potential for the production of compounds for biocontrol of plant pathogens. Four whole-genome sequenced B. toyonensis strains shared 3811 protein-coding DNA sequences (CDSs), while strain-specific CDSs, such as biosynthetic gene clusters of antimicrobials, were associated with specific chromosomal regions and mobile genetic elements of the strains. B. toyonensis strains had a higher frequency of putative bacteriocins gene clusters than that of Bacillus species traditionally used for the production of antimicrobials. In addition, gene clusters potentially involved in the production of novel bacteriocins were found in BAC3151, as well as biosynthetic genes of several other compounds, including non-ribosomal peptides, N-acyl homoserine lactonase and chitinases, revealing a genetic repertoire for antimicrobial synthesis greater than that of other Bacillus strains that have demonstrated effective activity against phytopathogens. This study showed for the first time that B. toyonensis has potential to produce various antimicrobials, and the analyses performed indicated that the endophytic strain BAC3151 can be useful for the development of new strategies to control microbial diseases in plants that are responsible for large damages in agricultural crops.

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