Navegando por Autor "Mantovani, Hilário Cuquetto"

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Acyl homoserine lactone-based quorum sensing stimulates biofilm formation by Salmonella Enteritidis in anaerobic conditions
(Archives of Microbiology, 2016-11-12) Almeida, Felipe Alves de; Pimentel-Filho, Natan de Jesus; Pinto, Uelinton Manoel; Mantovani, Hilário Cuquetto; Oliveira, Leandro Licursi de; Vanetti, Maria Cristina Dantas
Quorum sensing regulates a variety of phenotypes in bacteria including the production of virulence factors. Salmonella spp. have quorum sensing systems mediated by three autoinducers (AI-1, AI-2, and AI-3). The AI-1-mediated system is incomplete in that the bacterium relies on the synthesis of signaling molecules by other microorganisms. This study aimed to evaluate the influence of the AI-1 N-dodecanoyl-DL-homoserine lactone (C12-HSL) on the growth, motility, adhesion, and biofilm formation of Salmonella enterica serovar Enteritidis PT4 578 on a polystyrene surface. Experiments were conducted at 37 °C in anaerobic tryptone soy broth supplemented with C12-HSL and/or a mixture of four synthetic furanones, at the concentration of 50 nM each. The planktonic growth, adhesion, swarming, and twitching motility were not altered in the presence of C12-HSL and/or furanones under anaerobic conditions. However, C12-HSL induced biofilm formation after 36 h of cultivation as determined by quantification of biofilm formation, by enumeration of adhered cells to polystyrene coupons, and finally by imaging the presence of multilayered cells on an epifluorescence microscope. When furanones were present in the medium, an antagonistic effect against C12-HSL on the biofilm development was observed. The results demonstrate an induction of biofilm formation in Salmonella Enteritidis by AI-1 under anaerobic conditions. Considering that Salmonella does not produce AI-1 but respond to it, C12-HSL synthesized by other bacterial species could trigger biofilm formation by this pathogen in conditions that are relevant for its pathogenesis.
Antioxidant, antiproliferative, and immunostimulatory effects of cell wall α-d-mannan fractions from Kluyveromyces marxianus
(International Journal of Biological Macromolecules, 2017-11-11) Galinari, Éder; Almeida-Lima, Jailma; Macedo, Gorete Ribeiro; Mantovani, Hilário Cuquetto; Rocha, Hugo Alexandre Oliveira
This study evaluated the antioxidant, antiproliferative, and immunostimulatory properties of cell wall α-d-mannan fractions from yeast Kluyveromyces marxianus CCT7735. Filter centrifugation was used to obtain four fractions (KMM-1, KMM-2, KMM-3, and KMM-4) with molecular weight ranging from 7.6 to 75.1 kDa. KMM-1 and KMM-2 comprised D-mannose with traces of D-glucose, whereas other fractions contained only D-mannose. Total sugar found in samples ranged from 85.9% to 96.1%, while protein and phenolic contents were 1.21% and 0.41%, respectively. Although only KMM-1 was able to scavenge superoxide radicals, all fractions presented total antioxidant capacity as well as reducing power, hydroxyl-radical scavenging, and copper- and iron-chelating activities. No fraction was cytotoxic to HeLa cells. However, all samples inhibited the proliferation of the tumor cell Hep-G2 and presented minor cytotoxicity against normal 3T3 cells. All fractions showed mitogenic activity in macrophages and all, except KMM-4, induced nitric oxide production in macrophages, suggestive of their immunostimulatory effects.
Bacterial community dynamics across the gastrointestinal tracts of dairy calves during preweaning development
(Applied and Environmental Microbiology, 2018-05) Dias, Juliana; Marcondes, Marcos Inácio; Souza, Shirley Motta de; Silva, Barbara Cardoso da Mata e; Noronha, Melline Fontes; Resende, Rafael Tassinari; Machado, Fernanda Samarini; Mantovani, Hilário Cuquetto; Dill-McFarland, Kimberly A.; Suen, Garret
Microbial communities play critical roles in the gastrointestinal tracts (GIT) of preruminant calves by influencing performance and health. However, little is known about the establishment of microbial communities in the calf GIT or their dynamics during development. In this study, next-generation sequencing was used to assess changes in the bacterial communities of the rumen, jejunum, cecum, and colon in 26 crossbred calves at four developmental stages (7, 28, 49, and 63 days old). Alpha diversity differed among GIT regions with the lowest diversity and evenness in the jejunum, whereas no changes in alpha diversity were observed across developmental stage. Beta diversity analysis showed both region and age effects, with low numbers of operational taxonomic units (OTUs) shared between regions within a given age group or between ages in a given region. Taxonomic analysis revealed that several taxa coexisted in the rumen, jejunum, cecum, and colon but that their abundances differed considerably by GIT region and age. As calves aged, we observed lower abundances of taxa such as Bacteroides, Parabacteroides, and Paraprevotella with higher abundances of Bulleidia and Succiniclasticum in the rumen. The jejunum also displayed taxonomic changes with increases in Clostridiaceae and Turicibacter taxa in older calves. In the lower gut, taxa such as Lactobacillus, Blautia, and Faecalibacterium decreased and S24-7, Paraprevotella, and Prevotella increased as calves aged. These data support a model whereby early and successive colonization by bacteria occurs across the GIT of calves and provides insights into the temporal dynamics of the GIT microbiota of dairy calves during preweaning development. IMPORTANCE The gastrointestinal tracts (GIT) of ruminants, such as dairy cows, house complex microbial communities that contribute to their overall health and support their ability to produce milk. For example, the rumen microbiota converts feed into usable nutrients, while the jejunal microbiota provides access to protein. Thus, establishing a properly functioning GIT microbiota in dairy calves is critical to their productivity as adult cows. However, little is known about the establishment, maintenance, and dynamics of the calf GIT microbiota in early life. In this study, we evaluated the bacterial communities in the rumen, jejunum, cecum, and colon in dairy calves across preweaning development and show that they are highly variable early on in life before transitioning to a stable community. Understanding the dairy calf GIT microbiota has implications for ensuring proper health during early life and will aid in efforts to develop strategies for improving downstream production.
Bactericidal activity of ethanolic extracts of propolis against Staphylococcus aureus isolated from mastitic cows
(World Journal of Microbiology and Biotechnology, 2011-07-17) Santana, Henrique Freitas; Barbosa, Ana Andréa Teixeira; Ferreira, Sukarno Olavo; Mantovani, Hilário Cuquetto
Staphylococcus aureus is an important pathogen for both humans and animals, and it has been an ubiquitous etiological agent of bovine mastitis in dairy farms worldwide. Elimination of S. aureus with classic antibiotics is difficult, and the current study aimed to evaluate the efficacy of ethanolic extracts of propolis (EEP) against S. aureus cultivated in complex media or milk. EEP (0–0.5 mg ml^−1) decreased growth of S. aureus in BHI media and 1 mg ml^−1 was bactericidal against washed cell suspensions (10^7 CFU ml−1). Propolis extracts also killed S. aureus cells resuspended in milk, but the bactericidal dose was at least 20-fold greater. Cultures that were transferred for at least 60 generations with sub-lethal doses of propolis did not change much their sensibility to EEP. Atomic force microscopy images revealed changes in morphology and cell size of S. aureus cells exposed to EEP (0.5 mg ml^−1). Our results indicate that propolis extracts might be effective against mastitis-causing S. aureus strains in vivo, but milk constituents affect the inhibitory activity of propolis. Considering that propolis-resistance appears to be a phenotype not easily selected, the use of EEP combined or not with other antimicrobial agents might be useful for mastitis control in vivo.
Biochemical and genetic diversity of carbohydrate-fermenting and obligate amino acid-fermenting hyper-ammonia-producing bacteria from Nellore steers fed tropical forages and supplemented with casein
(BMC Microbiology, 2015-01-14) Bento, Cláudia Braga Pereira; Azevedo, Analice Cláudia de; Detmann, Edenio; Mantovani, Hilário Cuquetto
Dietary protein plays a major role in ruminant nutrition, and protein supplementation is a widespread practice among farmers in the tropics. Ruminal bacteria are the main agents of dietary protein and amino acid degradation, yet few studies have focused on the isolation and characterization of hyper-ammonia-producing bacteria in animals fed tropical diets or supplemented with rumen-degradable proteins. This work investigated the bacterial community diversity of the rumen of Nellore steers fed tropical forages, with or without casein supplementation. We also isolated and characterized ruminal bacteria showing high levels of ammonia production. Polymerase chain reaction–denaturing gradient gel electrophoresis analysis indicated no differences in the ruminal bacterial community composition between the control and supplemented animals. Amino acid-fermenting bacteria (n = 250) were isolated from crossbred Nellore steers fed Tifton 85 (Cynodon sp.) using trypticase as the sole carbon and organic nitrogen source in the enrichment and isolation media. The deamination rates in isolates obtained from steers supplemented with casein showed a higher incidence of deamination rates >350 nmol NH3 mg protein−1 min−1 (P < 0.05), whereas isolates obtained from steers without supplementation showed deamination rates <200 nmol NH3 mg protein−1 min−1. Although most isolates (84%) could ferment carbohydrates, none could hydrolyze proteins or use urea to sustain growth. All isolates were sensitive to lasalocid and monensin (1 μmol l−1), and similarity analysis of the 16S rRNA sequences indicated a predominance of bacteria from the order Clostridiales, with variable homology (73–99%) to known bacterial species. These results expand what is known about the biochemical and genetic diversity of hyper-ammonia-producing bacteria, and emphasize the role of carbohydrate-fermenting bacteria in ammonia production in the rumen.
Bovicin HC5 and nisin reduce Staphylococcus aureus adhesion to polystyrene and change the hydrophobicity profile and Gibbs free energy of adhesion
(International Journal of Food Microbiology, 2014-11-03) Pimentel-Filho, Natan de Jesus; Martins, Mayra Carla de Freitas; Nogueira, Guilherme Bicalho; Mantovani, Hilário Cuquetto; Vanetti, Maria Cristina Dantas
Staphylococcus aureus is an opportunistic pathogen often multidrug-resistant that not only causes a variety of human diseases, but also is able to survive on biotic and abiotic surfaces through biofilm communities. The best way to inhibit biofilm establishment is to prevent cell adhesion. In the present study, subinhibitory concentrations of the bacteriocins bovicin HC5 and nisin were tested for their capability to interfere with the adhesion of S. aureus to polystyrene. Subinhibitory dosages of the bacteriocins reduced cell adhesion and this occurred probably due to changes in the hydrophobicity of the bacterial cell and polystyrene surfaces. After treatment with bovicin HC5 and nisin, the surfaces became more hydrophilic and the free energy of adhesion (∆Gadhesion) between bacteria and the polystyrene surface was unfavorable. The transcriptional level of selected genes was assessed by RT-qPCR approach, revealing that the bacteriocins affected the expression of some important biofilm associated genes (icaD, fnbA, and clfB) and rnaIII, which is involved in the quorum sensing mechanism. The conditioning of food-contact surfaces with bacteriocins can be an innovative and powerful strategy to prevent biofilms in the food industry. The results are relevant for food safety as they indicate that bovicin HC5 and nisin can inhibit bacterial adhesion and consequent biofilm establishment, since cell adhesion precedes biofilm formation.
A central composite rotatable design (CCRD) approach to study the combined effect of antimicrobial agents against bacterial pathogens
(World Journal of Microbiology and Biotechnology, 2015-06-17) Santos, Fernanda Godoy; Mendonça, Layanne Andrade; Mantovani, Hilário Cuquetto
The combination of antimicrobial agents has been proposed as a therapeutic strategy to control bacterial diseases and to reduce the emergence of antibiotic-resistant strains in clinical environments. In this study, the interaction between the lantibiotic bovicin HC5 with chloramphenicol, gentamicin, nisin, lysostaphin and hydrogen peroxide against Staphylococcus aureus O46 was evaluated by MIC assays. The central composite rotatable design (CCRD), a robust and economic statistical design, was used to combine concentration levels of different antimicrobials agents with distinct mechanisms of action and the presence of significant interactions among the antimicrobials was determined by regression analysis. According to the adjusted model, there were no significant interactions between bovicin HC5 and gentamicin, lysostaphin, nisin or hydrogen peroxide. However, bovicin HC5 showed a significant interaction (P < 0.02) with chloramphenicol. This is the first study applying the CCRD approach to evaluate the combined effect of antimicrobials against S. aureus. Based on our results, this approach is an effective strategy to determine synergistic interactions between antimicrobial agents applied in human and veterinary medicine against bacterial pathogens.
The chemical composition, fermentation profile, and microbial populations in tropical grass silages
(Revista Brasileira de Zootecnia, 2013-04-08) Rigueira, João Paulo Sampaio; Pereira, Odilon Gomes; Ribeiro, Karina Guimarães; Mantovani, Hilário Cuquetto; Agarussi, Mariele Cristina Nascimento
The objective of this study was to evaluate the fermentation profile, chemical composition and microbial population and losses in the silages of signalgrass and Mombasa grass fertilized with the following levels of nitrogen (N): 0, 30, 60 and 90 kg/ha. The grasses were harvested at 70 days of regrowth, chopped and then ensiled in laboratory silos that had 20 kg of capacity and a snap-top cover and were fitted with Bunsen valves. Before ensiling, samples of the plants were used for the isolation and identification of lactic acid bacteria (LAB) in epiphytic microbiota. The design adopted was a 4 × 2 factorial arrangement, with four doses of N and two forage species, in a completely randomized design, with four replicates. The predominant species of LAB was Lactobacillus fermentum. The interaction between the N dose and forage species affected the dry matter (DM), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF) and water soluble carbohydrates (WSC) of the silages. The pH values and gas losses were influenced only by the forage species, with higher values for the Mombasa grass. For the ammonia (NH3-N) levels and effluent losses, there was an effect of the interaction between the forage species and N doses, and the highest values of NH3-N and effluent losses were found in the Mombasa grass silage fertilized with 60 kg N/ha. Nitrogen fertilization reduces the levels of DM and WSC in the silages and also increases the levels of CP, NH3-N and effluent losses.
Chemical structure, antiproliferative and antioxidant activities of a cell wall α-d-mannan from yeast Kluyveromyces marxianus
(Carbohydrate Polymers, 2017-02-10) Galinari, Éder; Sabry, Diego Araújo; Sassaki, Guilherme Lanzi; Macedo, Gorete Ribeiro; Passos, Flávia Maria Lopes; Mantovani, Hilário Cuquetto; Rocha, Hugo Alexandre Oliveira
Cell wall polysaccharides from filamentous fungi and yeasts have been reported as antioxidant and antiproliferative polymers. Thus, we evaluated these activities from cell wall polysaccharides from Kluyveromyces marxianus CCT7735. By using a centrifugal filter, a 203 kDa α-d-mannan (KMM-5) was obtained. KMM-5 exhibited no effect on HeLa cells and a weak antiproliferative activity against Hep-G2 cells. In addition, at higher concentrations, it presented a cytotoxicity to the normal cell line, 3T3. However, KMM-5 showed copper- and iron-chelating abilities, the latter of which presented improved activity. By using 2D-NMR COSY, HSQC edited and HMBC experiments, a structure arrangement was proposed. The main chain was formed by 6)-α-d-Manp-(1 → 6) units substituted at the 2-O-position by non-reducing terminals α-d-Manp-(1 → 2) and by a branched tetrasaccharide. The latter was formed by an internal 2)-α-d-Manp-(1 → 2) unit with linked to it a 2,3)-α-d-Manp-(1 → 2) unit substituted at the 2-O-position by a non-reducing terminal α-d-Manp-(1 → 2), and at the 3-O-position by a non-reducing terminal α-d-Manp-(1 → 3). In conclusion, we considered K. marxianus CCT7735 a source of natural and renewable polysaccharides with pharmacological properties.
Conscientização dos produtores de leite da Zona da Mata Mineira sobre métodos de prevenção da mastite bovina e isolamento dos seus agentes etiológicos
(Brazilian Journal of Sustainable Agriculture, 2011-12) Dias, Roberto Sousa; Duarte, Vinicius Silva; Favaro, Victor Lopes Ribeiro; Mantovani, Hilário Cuquetto; Silva, Cynthia Canêdo da; Silva, Eduardo de Almeida Marques da; Oliveira, Leandro Licursi de; Paula, Sérgio Oliveira De
A mastite causa perda da qualidade do leite e riscos à saúde dos consumidores em virtude da presença de resíduos de antibióticos e microrganismos patogênicos, além de sérios prejuízos econômicos tanto para o produtor quanto para a indústria de laticínios. O conhecimento referente aos agentes causadores da doença, à sua evolução clínica e a fatores relacionados com o estabelecimento da infecção deve ser colocado em prática em programas de controle e prevenção da doença, visando o treinamento dos produtores, principalmente em respeito ao manejo adequado de ordenha. Neste trabalho, buscamos conscientizar produtores de leite da Zona da Mata mineira sobre a importância do controle e prevenção de mastite bovina e determinar seus principais agentes etiológicos. Identificamos 3,3% de casos de mastite clínica, 15% de subclínica e 81,7% de tetos sadios em vacas leiteiras da região. Como principais agentes etiológicos, foram isolados o Staphylococcus aureus em 28,52% dos casos e o Staphylococcus sp., coagulase negativa, em 14,83%. Observamos também que poucos produtores da região possuem conhecimentos básicos sobre os métodos de prevenção e controle da mastite. Sendo assim, muitos carecem de programas de assistência técnica especializada, o que seria útil para o desenvolvimento de suas comunidades.
Degradação in vitro da fibra em detergente neutro de forragem tropical de alta qualidade em função da suplementação com proteína e/ou carboidratos
(Revista Brasileira de Zootecnia, 2008-10-27) Costa, Viviane Aparecida Carli; Detmann, Edenio; Valadares Filho, Sebastião de Campos; Paulino, Mário Fonseca; Henriques, Lara Toledo; Mantovani, Hilário Cuquetto
Objetivou-se avaliar o efeito da suplementação proteica e/ou com carboidratos sobre a degradação ruminal da fibra em detergente neutro (FDN) de forragem tropical de alta qualidade. No experimento, foi simulada a suplementação de bovinos em terminação sob pastejo durante o período chuvoso (70% de forragem e 30% de concentrado, com base na matéria seca). Como forragem basal utilizou-se amostra de capim-elefante (Pennisetum purpureum Schum.) cortado aos 21 dias de rebrotação. O concentrado utilizado no tratamento-base foi formulado de forma a apresentar 30% de proteína bruta, com amido como componente energético e caseína como componente proteico. Os tratamentos foram construídos mediante o não-fornecimento das fontes proteica e/ou energética do suplemento e substituição total do amido por pectina. Desta forma, avaliaram-se seis tratamentos (1. forragem; 2. forragem + amido; 3. forragem + pectina; 4. forragem + caseína; 5. forragem + caseína + amido; e 6. forragem + caseína + pectina) em ambiente ruminal simulado por incubação in vitro em diversos tempos de incubação: 0, 3, 6, 9, 12, 24, 36, 48, 72 e 96 horas. O procedimento de incubação foi repetido cinco vezes, perfazendo o total de cinco avaliações por tempo de incubação para cada tratamento. Os resíduos de incubação foram avaliados quanto ao teor de FDN e interpretados por intermédio de modelo não-linear logístico. A suplementação isolada com amido ou pectina reduziu em 9,9 e 8,4% a taxa de degradação da FDN potencialmente degradável (FDNpd). Efeitos similares foram verificados com a suplementação exclusivamente proteica, com redução de 19,1% sobre a taxa de degradação da FDNpd. A suplementação conjunta com proteína e carboidratos promove redução dos efeitos deletérios da suplementação isolada com esses compostos.
Degradação in vitro da fibra em detergente neutro de forragem tropical de baixa qualidade em função da suplementação com proteína verdadeira e/ou nitrogênio não-proteico
(Revista Brasileira de Zootecnia, 2010-06-10) Detmann, Edenio; Queiroz, Augusto César de; Zorzi, Karina; Mantovani, Hilário Cuquetto; Bayão, Geraldo Fábio Viana; Gomes, Matheus Pinto Coelho
Objetivou-se avaliar a dinâmica da degradação in vitro da fibra em detergente neutro (FDN) de forragem tropical de baixa qualidade em função da suplementação com compostos nitrogenados em diferentes relações proteína verdadeira:nitrogênio não-proteico (NNP). Amostra de capim-braquiária colhida durante a estação seca foi utilizada como forragem basal. Como fontes de proteína verdadeira e NNP, utilizaram-se a caseína e a mistura ureia:sulfato de amônia (U:SA; 9:1), respectivamente. O suplemento base para a definição dos demais foi constituído da adição de caseína ao meio de incubação de forma a elevar o teor de proteína bruta (PB) da forragem basal até 8%, com base na matéria seca. Os demais suplementos foram construídos a partir da substituição fracional (0, 1/3, 2/3 e 1) da PB da caseína por equivalentes proteicos da mistura U:SA, incluindo-se tratamento controle (forragem). Os tratamentos foram avaliados em ambiente ruminal simulado por incubação in vitro em diferentes tempos de incubação: 0, 3, 6, 9, 12, 24, 36, 48, 72 e 96 horas. O procedimento foi repetido três vezes, totalizando três avaliações por tempo de incubação para cada tratamento. Os resíduos de incubação foram avaliados quanto ao teor de FDN e interpretados por intermédio de modelo logístico não-linear. A suplementação proteica elevou em 56,8 a 96,0% a taxa de degradação da FDN potencialmente degradável (kFDNpd) em comparação ao suplemento controle e reduziu de 4,5 a 7,4 horas as estimativas de latência discreta. A utilização exclusiva de ureia elevou em 15,9% a estimativa de kFDNpd em relação à suplementação exclusiva com caseína. Contudo, valores máximos de kFDNpd e eficiência microbiana foram verificados sob a relação 2/3 PB U:SA:1/3 PB caseína. O balanceamento do suplemento de forma a prover 1/3 da PB a partir de proteína verdadeira e 2/3 da PB a partir de nitrogênio não-proteico otimiza a degradação da FDN de forragem de baixa qualidade.
Degradação in vitro da fibra em detergente neutro de forragem tropical de baixa qualidade em função de suplementação com proteína e/ou carboidratos
(Revista Brasileira de Zootecnia, 2007-09-11) Costa, Viviane Aparecida Carli; Detmann, Edenio; Valadares Filho, Sebastião de Campos; Paulino, Mário Fonseca; Henriques, Lara Toledo; Mantovani, Hilário Cuquetto
Objetivou-se avaliar o efeito da suplementação protéica e/ou com carboidratos sobre a degradação ruminal da fibra em detergente neutro (FDN) de forragem de baixa qualidade. Simulou-se a suplementação de bovinos em terminação, sob pastejo em Brachiaria decumbens de baixa qualidade, durante o período seco (70% de forragem e 30% de concentrado, com base na matéria seca). O concentrado referente ao tratamento base foi formulado de forma a apresentar 30% de proteína bruta, utilizando-se amido, como componente energético, e caseína, como componente protéico. Os tratamentos foram construídos a partir da omissão do fornecimento das fontes protéica e/ou energética do suplemento, associando-se, ainda, a substituição total do amido por pectina. Desta forma, seis foram os tratamentos avaliados: 1. forragem; 2. forragem + amido; 3. forragem + pectina; 4. forragem + caseína; 5. forragem + caseína + amido; e 6. forragem + caseína + pectina. Os tratamentos foram avaliados em ambiente ruminal simulado por incubação in vitro e submetidos a diferentes tempos de incubação: 0, 3, 6, 9, 12, 24, 36, 48, 72 e 96 horas. O procedimento de incubação foi repetido quatro vezes, perfazendo-se o total de quatro avaliações por tempo de incubação para cada tratamento. Os resíduos de incubação foram avaliados quanto ao teor de FDN e interpretados por intermédio de modelo não-linear logístico. Observou-se que a taxa de degradação da FDN potencialmente degradável (FDNpd) foi ampliada em cerca de 46% com a suplementação com caseína, resultando em incrementos de 14,6% sobre a fração efetivamente degradada. Observou-se efeito de menor amplitude com a inclusão ou alteração da fonte de carboidrato suplementar. A suplementação com amido causou redução na taxa de degradação da FDNpd, ao passo que a suplementação com pectina não afetou este parâmetro em comparação à ausência de carboidratos. Na presença de caseína, a suplementação com amido elevou o tempo de latência discreta para a degradação da FDN.
Efeito da monensina e da própolis sobre a atividade de fermentação de aminoácidos in vitro pelos microrganismos ruminais
(Revista Brasileira de Zootecnia, 2006-01) Oliveira, Juliana Silva de; Queiroz, Augusto César de; Lana, Rogério de Paula; Mantovani, Hilário Cuquetto; Generoso, Rafaela Antônia Ramos
Foram estudados os efeitos in vitro dos inibidores monensina e própolis sobre a fermentação ruminal de aminoácidos. Utilizou-se líquido ruminal de um novilho em pastejo, acrescentado de solução de tripticase, em três tratamentos (controle, monensina e própolis). Na 1ª fase do experimento, foram feitas transferências diárias de inóculos para novos tubos com os mesmos tratamentos até o 10º dia e, no 11º dia, iniciou a 2ª fase, efetuando-se as combinações dos tratamentos da 1ª fase (C, M, P), no total de nove, com transferência diária e incubação por mais nove dias. Do 1º ao 10º dia de incubação (1ª fase), o ionóforo e a própolis não aumentaram significativamente a produção de amônia em comparação ao controle. A própolis foi mais eficiente em dimiuir a produção de amônia que a monensina na 1ª fase e ainda reduziu a produção de amônia e a atividade específica de produção de amônia (AEPA) na 2ª fase, independentemente do tratamento aplicado na 1ª fase. Quando os inibidores estavam ausentes na 1ª fase, a monensina foi tão eficiente quanto a própolis na 2ª fase. Verificou-se que, ao remover os inibidores na 2ª fase no tratamento monesina, houve aumento significativo na produção de amônia, mas este efeito não foi detectado no tratamento com própolis, que manteve amônia em baixas concentrações.
Effect of propionic and lactic acids on in vitro ruminal bacteria growth
(Revista Brasileira de Zootecnia, 2010-11-03) Oliveira, Juliana Silva de; Queiroz, Augusto César de; Mantovani, Hilário Cuquetto; Melo, Marcelo Rodrigues de; Detmann, Edenio; Santos, Edson Mauro; Bayão, Geraldo Fábio Viana
The objective of this work was to evaluate the effect of the levels of lactic and propionic acids on in vitro fermentation of ruminal microorganisms. In experiment 1, the levels, in a total of 12 were the following: addition of 0 (control 1), 50, 100, 150, 200 and 250 mM of lactic acid and 0 (control 2), 50, 100, 150, 200 and 250 mM of propionic acid, respectively, in incubation flasks, which contained ruminal inoculum, glucose and synthetic culture medium, with two repetitions for each combination. In experiment 2, the combinations, in a total of 4, were the following: presence of 12 and 24 mM of propionic acid and 0 mg of glucose, respectively; presence of 12 and 24 mM of propionic acid and 40 mg of glucose, respectively, to the incubation flasks which contained ruminal inoculum, with or without glucose and in synthetic culture medium with two repetitions each. There was no effect on the specific growth velocity of ruminal microorganisms in the presence of lactic acid or propionic acid. However, when there were greater concentrations of these acids in the media, there was a longer lag phase in the microorganism phase. Acid propionic at the concentration of 24 mM inhibited the production of acid acetic and butyric acid in a media with glucose. Despite of not being used as a source of energy by the ruminal microorganisms, propionic acid affects their metabolism. Lactic and propionic acids inhibit growth of some ruminal microorganisms at elevated concentrations.
Effect of whey fermented by Enterococcus faecium in consortium with Veilonella parvula on ruminal bacteria in vitro
(Revista Brasileira de Zootecnia, 2014-01-30) Bezerra, Higor Fábio Carvalho; Oliveira, Juliana Silva de; Santos, Edson Mauro; Queiroz, Augusto César de; Mantovani, Hilário Cuquetto; Pinho, Ricardo Martins Araujo; Oliveira Junior, Jurandir Queiroz de; Costa, Elizabete Cristina Batista da
The objective of this research was to evaluate the effect of whey fermented by Enterococus faecium in consortium with Veilonella parvula in vitro on ruminal microorganisms in different substrates, with or without monensin. The first experiment was carried out in a completely randomized design, in a 6 × 3 factorial arrangement (six substrates × three whey levels) with two replicates. In experiment two, a 2 × 3 × 4 factorial arrangement (with and without monensin, three foods and four levels of fermented whey) was used, in a randomized design with four replicates, totaling 24 treatments. There was no interaction among the wheys and the substrates in the variable for pectin, starch, and carboxymethyl cellulose. There was a greater growth of amylolytic and pectinolytic microorganisms and a lower growth of proteolytic and cellulolytic microorganisms. A significant effect of optical density was found in the media without substrate and that containing trypticase and glucose due to the addition of fermented whey. There was interaction for the pH at 24 hours among whey, food and monensin. For ammonia at 24 hours there was effect for food, whey and monensin, and interaction among factors. For microbial protein at 24 hours, there was effect for food, whey, monensin and no interaction among sources of variation. The use of whey fermented by bacteria Enterococcus faecium and Veilonella parvula improves microbial protein synthesis by ruminal bacteria in media containing different energy sources. The combination of fermented whey and monensin shows variable results in relation to microbial growth.
Effects of corn processing on piglet performance and intestinal parameters
(Brazilian Journal of Animal Science, 2020-11-18) Scalco, Tiago; Valini, Graziela Alves da Cunha; Silva, Caroline Brito da; Calderano, Arele Arlindo; Rodrigues, Gustavo de Amorim; Campos, Paulo Henrique Reis Furtado; Mantovani, Hilário Cuquetto; Sanglard, Letícia Maria Pereira; Rocha, Gabriel Cipriano
The objective of the present study was to compare the effects of corn processing on performance and intestinal parameters of weanling piglets. To accomplish our goal, 42 piglets (21 days-old, 7.18±1.0 kg body weight) were randomly allocated (seven pens/treatment; three pigs/pen) to one of two treatments: ground corn – corn ground through a hammer mill with a 1.0-mm screen after being ground by a hammer mill with a 3.0-mm screen, and extruded corn – corn was wet extruded after being ground by a hammer mill with a 2.0-mm screen and, after extrusion, it was ground by a hammer mill with a 1.0-mm screen. In both methods, corn from the same batch was used. Results were considered statistically significant when P<0.05 and a tendency when P<0.10. Analyses were performed using the GLIMMIX procedure of SAS. Pigs fed ground or extruded corn diet had similar growth performance. Duodenum and jejunum of pigs fed extruded corn had greater villus height compared with those of pigs fed ground corn. Crypt depth was not influenced by corn processing. Duodenum and jejunum of pigs fed extruded corn had greater villus:crypt ratio compared with those of pigs fed ground corn. In the duodenum, the expression of zonula occludens-1 (ZO-1) was greater, and the expression of Occludin-1 tended to be greater in pigs fed the extruded corn diets. There was no effect of corn processing on ZO-1 and Occludin-1 expression in the jejunum, nor TGF-β1 expression in duodenum and jejunum. There was no effect of the type of corn processing on colonic total bacteria or Enterobacteriaceae and Lactobacillus abundance. Piglets fed diets with ground corn or extruded corn have similar growth performance. However, piglets fed diets with extruded corn present improved intestinal morphology and tight junction protein expression compared with those fed ground corn
Evaluation of whey fermented by Enterococcus faecium in consortium with Veilonella parvula in ruminant feeding
(Revista Brasileira de Zootecnia, 2011-06-01) Oliveira, Juliana Silva de; Queiroz, Augusto César de; Mantovani, Hilário Cuquetto; Bayão, Geraldo Fábio Viana; Detmann, Edenio; Santos, Edson Mauro; Silva, Thiago Carvalho da
The objective of this study was to evaluate the whey fermented by Enterococcus faecium in consortium with Veilonella parvula on the in vitro growth of ruminal bacteria and as a supplement in the cattle diet. In the in vitro experiment, a randomized design, with the following combinations was used: ruminal bacteria; ruminal bacteria and inactive whey; ruminal bacteria and active whey; and active whey. In the in vivo experiment, five fistulated Zebu Holstein-Zebu crossbred heifers were distributed in a 5 × 5 Latin square. Supplements were formulated without the addition of whey, with the addition of two levels of unfermented whey (2.5 and 5 L/day) or two levels of fermented whey (2.5 and 5 L/day). A positive effect of the whey fermentation was detected on the consumption of dry matter, organic matter, crude protein, ether extract, non-fiber carbohydrates and neutral detergent fiber, corrected for ash and protein in kg/day. No effects of whey were observed on the pH and concentration of rumen ammonia nitrogen, serum concentration of urea and glucose, urinary excretion of urea or nutrient digestibility, except for the total digestible nutrients. Supplementation with whey improved the apparent nitrogen balance, but supplementation with fermented whey decreased the intestinal flow of microbial nitrogen and microbial synthesis efficiency in relation to the unfermented whey. The whey fermentation process does not optimize the physiological responses of heifers supplemented with 2.5 and 5.0 L of whey.
Growth and antimicrobial activity of lactic acid bacteria from rumen fluid according to energy or nitrogen source
(Revista Brasileira de Zootecnia, 2010-12-08) Carvalho, Isabela Pena Carvalho de; Detmann, Edenio; Mantovani, Hilário Cuquetto; Paulino, Mário Fonseca; Valadares Filho, Sebastião de Campos; Costa, Viviane Aparecida Carli; Gomes, Daiany Iris
The objective of this study was to evaluate the effects of supplementation with different sources of energy and nitrogenous compounds on the in vitro growth and production of bacteriocin of lactic acid bacteria. Incubations were performed by using ruminal fluid from a rumen-fistulated Holstein-Zebu steer. The animal was kept on a Brachiaria decumbens pasture receiving 200 g/day of supplemental crude protein. Substrates and inoculum were placed in glass flasks considering eight treatments: cellulose, cellulose and casein, cellulose and soy peptone, cellulose and urea, starch, starch and casein, starch and soy peptone and starch and urea. Successive incubations were conducted to select microorganisms according to the energy sources and nitrogenous compounds. Starch favoured growth of lactic acid bacteria when compared to cellulose. Supplementation with true protein (soy peptone and casein) stimulated the growth of these bacteria when compared to the control (without supplementation with nitrogenous compounds). The addition of urea did not stimulate the growth of lactic acid bacteria. No antimicrobial activity was detected from colonies of isolated lactic acid bacteria. Sources of true protein increase the competition between non-structural and structural carbohydrates fermenting bacteria.
In vitro and in situ activity of carboxymethyl cellulase and glutamate dehydrogenase according to supplementation with different nitrogenous compounds
(Revista Brasileira de Zootecnia, 2011-08-23) Carvalho, Isabela Pena Carvalho de; Detmann, Edenio; Paulino, Mário Fonseca; Mantovani, Hilário Cuquetto; Valadares Filho, Sebastião de Campos; Gomes, Daiany Iris; Costa, Viviane Aparecida Carli
Two experiments were carried out to evaluate the effect of supplementation with different nitrogenous compounds on the activities of carboxymethil cellulase (CMCase) and glutamate dehydrogenase (GDH). In the first experiment, four treatments were evaluated in vitro: cellulose, cellulose with casein, cellulose with urea, and cellulose with casamino acids. After 6, 12 and 24 hours of incubation, CMCase and GDH activity, pH, and concentrations of ammonia nitrogen (AN) and microbial protein were measured. In the three incubation periods, the concentration of AN was higher when urea was used as a supplemental source of nitrogen. The activity of CMCase was higher with the addition of urea and casamino acids when compared with the control and the casein treatment. Supplementation with casamino acids provided higher GDH activity when compared with the control at 6 hours of incubation. At 12 hours of incubation, the GHD activity was also stimulated by casein. At 24 hours, there was no difference in GHD activity among treatments. In the second experiment, three rumen-fistulated bulls were used for in situ evaluation. Animals were fed Tifton hay (Cynodon sp.) ad libitum. The treatments consisted of control (no supplementation), supplementation with non-protein nitrogenous compounds (urea and ammonium sulphate, 9:1) and supplementation with protein (albumin). In treatments with nitrogenous compound supplementation, 1 g of crude protein/kg of body weight was supplied. The experiment was conducted in a 3 × 3 Latin square design. The measurements were performed at 6, 12 and 24 hours after supplementation. No difference in GDH activity was observed among treatments. The control treatment showed higher CMCase activity when compared with the treatments containing supplemental sources of nitrogen. However, urea supplementation provided higher CMCase activity compared to albumin.