Performance and morphology of intestinal mucosa of broilers fed mannan-oligosaccharides and enzymes

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Genotypes of the mannan-binding lectin gene and susceptibility to visceral leishmaniasis and clinical complications

Background. Visceral leishmaniasis (VL) is almost always lethal if not treated, but most infections with the causative agents are clinically silent. Mannan-binding lectin (MBL), an opsonin, is a candidate molecule for modifying progression to VL because it may enhance infection with intracellular pathogens. Mutations in the MBL2 gene decrease levels of MBL and may protect against development of VL. This case-control study examines genotypes of MBL2 and levels of MBL in individuals presenting with different outcomes of infection with Leishmania chagasi.Methods. Genotypes for MBL2 and levels of serum MBL were determined in uninfected control subjects (n=76) and in individuals presenting with asymptomatic infection (n=90) or VL (n=69).Results. Genotypes resulting in high levels of MBL were more frequent (odds ratio [OR], 2.5 [95% confidence interval {CI}, 1.3-5.0]; P=.006) among individuals with VL than among those with asymptomatic infections and were even more frequent (OR, 3.97 [95% CI, 1.10-14.38];P=.043) among cases of VL presenting with clinical complications than among those with uneventful courses. Serum levels of MBL were higher (P=.011) in individuals with VL than in asymptomatic infections.Conclusions. Genotypes of the MBL2 gene predict the risk for developing VL and clinical complications in infections with L. chagasi.

Protective effect of mannan oligosaccharides against early colonization by Salmonella Enteritidis in chicks is improved by higher dietary threonine levels

Aims: To evaluate mannan oligosaccharide (MOS) and threonine effects on performance, small intestine morphology and Salmonella spp. counts in Salmonella Enteritidis-challenged birds. Methods and Results: One-day-old chicks (1d) were distributed into five treatments: nonchallenged animals fed basal diet (RB-0), animals fed basal diet and infected with Salmonella Enteritidis (RB-I), animals fed high level of threonine and infected (HT-I), birds fed basal diet with MOS and infected (MOS-I), birds fed high level of threonine and MOS and infected (HT+MOS-I). Birds were inoculated at 2d with Salmonella Enteritidis, except RB-0 birds. Chicks fed higher dietary threonine and MOS showed performance similar to RB-0 and intestinal morphology recovery at 8 dpi. Salmonella counts and the number of Salmonella-positive animals were lower in HT+MOS-I compared with other challenged groups. Conclusion: Mannan oligosaccharides and threonine act synergistically, resulting in improved intestinal environment and recovery after Salmonella inoculation. Significance and Impact of the Study: Nutritional approaches may be useful to prevent Salmonella infection in the first week and putative carcass contamination at slaughter. This is the first report on the possible synergistic effect of mannan oligosaccharides and threonine, and further studies should be performed including performance, microbiota evaluation, composition of intestinal mucins and immune assessment. © 2012 The Society for Applied Microbiology.

Utilização de nutrientes de dietas contendo mananoligossacarídeo e/ou complexo enzimático para frangos de corte

Avaliaram-se a digestibilidade ileal e a retenção de alguns nutrientes e os valores de energia de dietas contendo mananoligossacarídeo (MOS) e/ou complexo enzimático (CE) para frangos de corte. Foram utilizadas 275 aves em delineamento em blocos ao acaso e arranjo fatorial 2 x 2 + 1, com dois níveis de MOS (0 e 0,1%), dois níveis de complexo enzimático (0 e 0,05%) e uma dieta controle positivo com antibióticos. O óxido crômico (0,5%) foi adicionado às dietas para estimativa do fator de indigestibilidade. O experimento teve início quando as aves completaram 13 dias de idade; a coleta de excretas foi realizada do 20º ao 22º dia e a de digesta, no 23º dia de idade das aves. A interação MOS × CE foi significativa para a retenção de PB e P e de energia metabolizável aparente (EMA), cujos valores foram maiores nas dietas com MOS e CE. A inclusão do CE melhorou a retenção de MS e os coeficientes de digestibilidade ileal de MS, PB, Ca e P na retenção de cálcio e nos valores de energia digestível com a inclusão de mananoligossacarídeo. Os coeficientes de digestibilidade ileal da MS, a retenção de MS, PB, Ca e P e os valores de energia digestível e de EMA das dietas contendo MOS e/ou CE foram superiores aos obtidos com a dieta contendo antibióticos.

Mananoligossacarídeos e complexo enzimático em dietas para frangos de corte

Avaliou-se o efeito de dietas com mananoligossacarídeos e complexo enzimático (CE) sobre o desempenho, a morfologia intestinal e a qualidade da cama de frangos aos 42 dias de idade. Foram utilizadas 750 aves em delineamento inteiramente casualizado em esquema fatorial 2 × 2 + 1, com dois níveis de mananoligossacarídeos (0 e 0,1% de 1 a 21 dias e 0,05% de 22 a 42 dias de idade), dois níveis de complexo enzimático (0 e 0,05%) e uma dieta com antibióticos (CP), totalizando cinco dietas com cinco repetições. Aos 42 dias de criação, o desempenho foi avaliado e, após o abate das aves, foram coletadas amostras de intestino e de cama e avaliado o desempenho. A inclusão de mananoligossacarídeos e/ou complexo enzimático na dieta não afetou o desempenho das aves, o perímetro e a altura dos vilos duodenais, a profundidade de criptas, a densidade de vilos no duodeno, jejuno e íleo, os teores de matéria seca e nitrogênio total e o pH das camas. A interação mananoligossacarídeos × complexo enzimático foi significativa para perímetro e altura de vilos no jejuno, que foram maiores nas aves alimentadas com as rações sem complexo enzimático e mananoligossacarídeos, mesmo comportamento observado para perímetro e altura de vilos ileais. Entretanto, quando adicionados mananoligossacarídeos e complexo enzimático, os valores dessas variáveis reduziram. A volatilização de amônia aumentou em camas de frango tratados com antibióticos e diminuiu com a adição de mananoligossacarídeos à dieta. A adição de mananoligossacarídeos ou complexo enzimático às dietas aumentou o perímetro e altura de vilos da mucosa do jejuno e do íleo e reduziu a volatilização de amônia da cama.

Mananoligossacarídeos em dietas para frangos de corte

Objetivou-se avaliar dietas contendo mananoligossacarídeos (MOS) como aditivo alternativo aos promotores de crescimento por meio do estudo da morfometria do intestino e do desempenho de frangos de corte. Para tanto, 1280 pintos de corte foram distribuídos em delineamento inteiramente casualizado com quatro tratamentos (controle negativo, CN: dieta isenta de antibiótico; controle positivo, CP: dieta contendo antibiótico e duas dietas, MOS 1 e MOS 2, nas quais foram adicionadas ao CN duas fontes distintas de MOS) e oito repetições, sendo a unidade experimental composta por 40 aves. Para submeter as aves ao desafio sanitário, foi formulada uma dieta basal com milho, farelo de soja e farinha de carne e ossos. Adotou-se cama reutilizada, limpeza dos bebedouros duas vezes por semana e oferta semanal de água contaminada com cama. Foram avaliadas altura de vilo e profundidade de cripta do duodeno, jejuno e íleo, consumo da dieta, peso médio, ganho de peso e conversão alimentar das aves. Houve melhora na profundidade de cripta no jejuno e na altura de vilo no íleo das aves alimentadas com dietas contendo MOS. A adição de MOS, independente da fonte, resultou em melhor conversão alimentar em relação às aves do CN, sendo similares às aves do CP. Os mananoligossacarídeos podem ser utilizados como aditivo alternativo aos promotores de crescimento em dietas para frangos de corte, porém, dependendo da fonte, esta pode acarretar em pequenas diferenças no desempenho das aves.

Humoral immune response of broilers fed diets containing yeast extract and prebiotics in the prestarter phase and raised at different temperatures

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Genotoxicity, cytotoxicity and gene expression in patients undergoing elective surgery under isoflurane anaesthesia

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Functional characterization and target discovery of glycoside hydrolases from the digestome of the lower termite Coptotermes gestroi

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Eletrólise de resíduos poluidores: I - Efluente de uma indústria liofilizadora de condimentos

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Anti-Candida targets and cytotoxicity of casuarinin isolated from Plinia cauliflora leaves in a bioactivity-guided study

In addition to the bio-guided investigation of the antifungal activity of Plinia cauliflora leaves against different Candida species, the major aim of the present study was the search for targets on the fungal cell. The most active antifungal fraction was purified by chromatography and characterized by NMR and mass spectrometry. The antifungal activity was evaluated against five Candida strains according to referenced guidelines. Cytotoxicity against fibroblast cells was determined. The likely targets of Candida albicans cells were assessed through interactions with ergosterol and cell wall composition, porosity and architecture. The chemical major component within the most active antifungal fraction of P. cauliflora leaves identified was the hydrolysable tannin casuarinin. The cytotoxic concentration was higher than the antifungal one. The first indication of plant target on cellular integrity was suggested by the antifungal activity ameliorated when using an osmotic support. The most important target for the tannin fraction studied was suggested by ultrastructural analysis of yeast cell walls revealing a denser mannan outer layer and wall porosity reduced. It is possible to imply that P. cauliflora targeted the C. albicans cell wall inducing some changes in the architecture, notably the outer glycoprotein layer, affecting the cell wall porosity without alteration of the polysaccharide or protein level. © 2013 by the authors.

Structure-function relationships of the peptide Paulistine: A novel toxin from the venom of the social wasp Polybia paulista

Background: The peptide Paulistine was isolated from the venom of wasp Polybia paulista. This peptide exists under a natural equilibrium between the forms: oxidised - with an intra-molecular disulphide bridge; and reduced - in which the thiol groups of the cysteine residues do not form the disulphide bridge. The biological activities of both forms of the peptide are unknown up to now. Methods: Both forms of Paulistine were synthesised and the thiol groups of the reduced form were protected with the acetamidemethyl group [Acm-Paulistine] to prevent re-oxidation. The structure/activity relationships of the two forms were investigated, taking into account the importance of the disulphide bridge. Results: Paulistine has a more compact structure, while Acm-Paulistine has a more expanded conformation. Bioassays reported that Paulistine caused hyperalgesia by interacting with the receptors of lipid mediators involved in the cyclooxygenase type II pathway, while Acm-Paullistine also caused hyperalgesia, but mediated by receptors involved in the participation of prostanoids in the cyclooxygenase type II pathway. Conclusion: The acetamidemethylation of the thiol groups of cysteine residues caused small structural changes, which in turn may have affected some physicochemical properties of the Paulistine. Thus, the dissociation of the hyperalgesy from the edematogenic effect when the actions of Paulistine and Acm-Paulistine are compared to each other may be resulting from the influence of the introduction of Acm-group in the structure of Paulistine. General significance: The peptides Paulistine and Acm-Paulistine may be used as interesting tools to investigate the mechanisms of pain and inflammation in future studies. © 2013 Elsevier B.V.