Weissella paramesenteroides WpK4 reduces gene expression of intestinal cytokines, and hepatic and splenic injuries in a murine model of typhoid fever.

Diarrhoea in piglets by Salmonella and other pathogens can be a serious health problem. Non-drug treatments such as probiotic microorganisms have various effects on the gastrointestinal microbiota dysbiosis and host immune system modulation. The aim of this study was to demonstrate the suitable use of Weissella paramesenteroides WpK4 strain isolated from healthy piglets as an alternative prophylactic or therapeutic treatment against Salmonella Typhimurium. Out of 37 lactic acid bacteria isolates, 24 strains belonging to the Weissella and Lactobacillus genera were analysed in vitro for desirable probiotic characteristics. The W. paramesenteroides WpK4 strain fulfilled all in vitro tests: resistance to acidic pH and bile salts, hydrophobic cell surface, antagonism against bacterial pathogens, H2O2 production and exopolysaccharide secretion, and non-transferable resistance to antibiotics. Mice fed with WpK4 showed no signs of bacterial translocation to the liver or spleen and decreased Salmonella translocation to these organs. Significantly, WpK4 intake attenuated the weight loss, fostered the preservation of intestinal architecture and integrity, and promoted survival in mice following infection with Salmonella Typhimurium. In addition, WpK4 modulated immune cellular response by inhibiting the production of pro-inflammatory cytokines and inducing anti-inflammatory mediators. These findings validate the probiotic properties of W. paramesenteroides WpK4 strain, and its eventual use in piglets.

High Incubation Temperature and Threonine Dietary Level Improve Ileum Response Against Post-Hatch Salmonella Enteritidis Inoculation in Broiler Chicks.

This study assessed the effect of both embryonic thermal manipulation and dietary threonine level on the response of broilers inoculated with Salmonella Enteritidis, considering bacterial counts in the cecal contents, intestinal morphology, mucin and heat shock protein 70 gene expression, body weight and weight gain. Thermal manipulation was used from 11 days of incubation until hatch, defining three treatments: standard (37.7°C), continuous high temperature (38.7°C) and continuous low temperature (36.7°C). After hatch, chicks were distributed according to a 3x2+1 factorial arrangement (three temperatures and two threonine levels and one sham-inoculated control). At two days of age, all chicks were inoculated with Salmonella Enteritidis, except for the sham-inoculated control group. There was no interaction between the factors on any analyses. High temperature during incubation was able to reduce colonization by Salmonella Enteritidis in the first days, reducing both Salmonella counts and the number of positive birds. It also increased mucin expression and decreased Hsp70 expression compared with other inoculated groups. High temperature during incubation and high threonine level act independently to reduce the negative effects associated to Salmonella Enteritidis infection on intestinal morphology and performance, with results similar to sham-inoculated birds. The findings open new perspectives for practical strategies towards the pre-harvest Salmonella control in the poultry industry.

Comportamento de células do sistema imune frente ao desafio com Salmonella Enteritidis em aves tratadas e não tratadas com ácidos orgânicos / Behavior of cells of immune system to the challenge with Salmonella Enteritidis in birds treated and untreated with organic acids

A Salmonelose é uma importante zoonose, considerada a principal causa de infecções bacterianas, sendo associada ao consumo de produtos avícolas. Como alternativa de controle, ácidos orgânicos têm sido amplamente usados. No entanto, pouco se conhece sobre o estado imunológico de aves de produção, e uma avaliação deste status é necessária para proteger frente a enfermidades e para garantir à aplicação segura de agentes terapêuticos ou imunização profilática. Este trabalho teve como objetivo verificar o comportamento do sistema imunológico das aves previamente infectadas com Salmonella Enteritidis (SE) tratadas com um composto de ácidos orgânicos em diferentes concentrações administrado via água e ração comparando com as aves infectadas e não tratadas. Foram inoculados 120 frangos de corte com 1mL de SE, via oral, na concentração de 1,0 x 108 UFC/mL, no 1º e 2º dia de idade, divididos em seis tratamentos com duas repetições, utilizando 200, 400, 500 e 1000ppm do ácido orgânico. Aos 35 dias de vida das aves, foram coletados, de todos os grupos, alíquotas de sangue de 3mL em tubo contendo EDTA para a avaliação das células imunes através de citometria de fluxo. Foram analisadas as porcentagens circulantes de células CD4+, CD8β+, MHC I+, MHC II+, TCRVβ1+, TCRVβ2+ e CD28+. Para análise microbiológica foram coletadas tonsilas cecais destas aves. Observou-se com esse estudo que os ácidos orgânicos nas dosagens 1000ppm na água e 500ppm na ração durante, dois e sete dias respectivamente antes do abate, foram eficazes na redução da infecção por SE em frangos de corte, comprovadas pelo método microbiológico e demonstradas através do comportamento das células do sistema imune. No presente estudo as aves infectadas apresentaram uma proporção menor de células T auxiliares circulantes quando comparadas às aves infectadas, mas tratadas com o AO ou com o grupo não infectado. A mesma tendência pode ser observada para as células CD28+, TCRVβ1+ e MHC IIbright+, e, com menor resolução, para CD8β+.(AU)

Salmonellosis is an important zoonosis, considered the leading cause of bacterial infections, and is associated with the consumption of poultry products. As alternative control, organic acids have been widely used. However, little is known about the immune status of poultry production, and an evaluation of this status is necessary to protect against disease and to ensure the safe application of therapeutic agents or prophylactic vaccination. This study aimed to verify the behavior of the immune system of birds previously infected with Salmonella Enteritidis (SE) treated with a compound of organic acids in different concentrations administered via water and food, compared with the infected birds and untreated. One hundred and twenty broilers were orally inoculated with 1ml of SE at a concentration of 1.0x108 CFU/mL, at 1 and 2-days-old and divided into six treatments with two repetitions of 200, 400, 500 and 1000ppm organic acid. From 35-days-old birds of all groups were collected aliquots of 3mL of blood into a tube containing EDTA for the evaluation of immune cells by flow cytometry. We then analyzed the percentages of circulating CD4+, CD8β+, MHC I+ MHC II+, TCRVβ1+, CD28+ + and TCRVβ2. For microbiological analysis were collected caecal tonsils of these birds. We found that organic acids in dosages 1000ppm 500ppm in water and in feed for 2 to 7 days before slaughter, respectively, were effective in reducing SE infection in broilers, proven by microbiological method and demonstrated through the behavior of immune cells. The infected birds showed a lower proportion of circulating T helper cells compared with infected poultry, but treated with AO or with the uninfected group. The same trend can be observed for CD28+ cells, and MHC IIbright+ TCRVβ 1+, and with lower resolution, for CD8β+.(AU)

Comportamento de células do sistema imune frente ao desafio com Salmonella Enteritidis em aves tratadas e não tratadas com ácidos orgânicos / Behavior of cells of immune system to the challenge with Salmonella Enteritidis in birds treated and untreated with organic acids

A Salmonelose é uma importante zoonose, considerada a principal causa de infecções bacterianas, sendo associada ao consumo de produtos avícolas. Como alternativa de controle, ácidos orgânicos têm sido amplamente usados. No entanto, pouco se conhece sobre o estado imunológico de aves de produção, e uma avaliação deste status é necessária para proteger frente a enfermidades e para garantir à aplicação segura de agentes terapêuticos ou imunização profilática. Este trabalho teve como objetivo verificar o comportamento do sistema imunológico das aves previamente infectadas com Salmonella Enteritidis (SE) tratadas com um composto de ácidos orgânicos em diferentes concentrações administrado via água e ração comparando com as aves infectadas e não tratadas. Foram inoculados 120 frangos de corte com 1mL de SE, via oral, na concentração de 1,0 x 108 UFC/mL, no 1º e 2º dia de idade, divididos em seis tratamentos com duas repetições, utilizando 200, 400, 500 e 1000ppm do ácido orgânico. Aos 35 dias de vida das aves, foram coletados, de todos os grupos, alíquotas de sangue de 3mL em tubo contendo EDTA para a avaliação das células imunes através de citometria de fluxo. Foram analisadas as porcentagens circulantes de células CD4+, CD8β+, MHC I+, MHC II+, TCRVβ1+, TCRVβ2+ e CD28+. Para análise microbiológica foram coletadas tonsilas cecais destas aves. Observou-se com esse estudo que os ácidos orgânicos nas dosagens 1000ppm na água e 500ppm na ração durante, dois e sete dias respectivamente antes do abate, foram eficazes na redução da infecção por SE em frangos de corte, comprovadas pelo método microbiológico e demonstradas através do comportamento das células do sistema imune. No presente estudo as aves infectadas apresentaram uma proporção menor de células T auxiliares circulantes quando comparadas às aves infectadas, mas tratadas com o AO ou com o grupo não infectado. A mesma tendência pode ser observada para as células CD28+, TCRVβ1+ e MHC IIbright+, e, com menor resolução, para CD8β+.

Salmonellosis is an important zoonosis, considered the leading cause of bacterial infections, and is associated with the consumption of poultry products. As alternative control, organic acids have been widely used. However, little is known about the immune status of poultry production, and an evaluation of this status is necessary to protect against disease and to ensure the safe application of therapeutic agents or prophylactic vaccination. This study aimed to verify the behavior of the immune system of birds previously infected with Salmonella Enteritidis (SE) treated with a compound of organic acids in different concentrations administered via water and food, compared with the infected birds and untreated. One hundred and twenty broilers were orally inoculated with 1ml of SE at a concentration of 1.0x108 CFU/mL, at 1 and 2-days-old and divided into six treatments with two repetitions of 200, 400, 500 and 1000ppm organic acid. From 35-days-old birds of all groups were collected aliquots of 3mL of blood into a tube containing EDTA for the evaluation of immune cells by flow cytometry. We then analyzed the percentages of circulating CD4+, CD8β+, MHC I+ MHC II+, TCRVβ1+, CD28+ + and TCRVβ2. For microbiological analysis were collected caecal tonsils of these birds. We found that organic acids in dosages 1000ppm 500ppm in water and in feed for 2 to 7 days before slaughter, respectively, were effective in reducing SE infection in broilers, proven by microbiological method and demonstrated through the behavior of immune cells. The infected birds showed a lower proportion of circulating T helper cells compared with infected poultry, but treated with AO or with the uninfected group. The same trend can be observed for CD28+ cells, and MHC IIbright+ TCRVβ 1+, and with lower resolution, for CD8β+.