Salmonella typhimurium vaccine to control a brazilian Salmonella heidelberg strain in broiler chickens / Vacina de Salmonella typhimurium para controlar cepa brasileira de Salmonella heidelberg em frangos de corte

Foodborne Salmonella infections in humans, which results from the consumption of contaminated poultry meat and eggs, are a major public health concern. Vaccination of animals against Salmonella is one strategy to prevent these infections and reduce the risks to public health. Live attenuated Salmonella enterica vaccines can confer protection against salmonellosis by inducing both cell-mediated and mucosal immune responses. This study assessed a live, attenuated Salmonella enterica Typhimurium (ST) vaccine in broiler chickens against a heterologous challenge with Salmonella Heidelberg (SH) by evaluating bacterial quantification, immune cells infiltration, and cytokine gene expression in the cecum. The treatments were: T1, non-vaccinated, non-challenged; T2, non-vaccinated, SH-challenged; T3, ST-vaccinated and SH-challenged. At 28 days of age, the ST-vaccinated group had significantly recovered reduction of SH in the crop (P<0,01) and cecum (P = 0,021) compared to the non-vaccinated SH-challenged group, with no significant changes (P˃0,05) in macrophages, T CD4+, or T CD8+ cells dynamics during the same period. Aerosol vaccination on the first day promoted greater interleukin-12 expression in the liver (P<0,05) and interleukin-10 expression and T CD8+ cells in the ileum 16 hours after housing. After prime-boosted oral immunization on the 13th day, the vaccinated group had greater expression of macrophages and T CD4+ cells in the liver (P<0,05) than the control group. Two doses of a live ST-attenuated vaccine promoted a partial cross-protective effect against SH strain UFPR1 challenge in broilers.(AU)

Infecções por Salmonella transmitidas por alimentos como consumo de carne de frango e ovos contaminados em seres humanos constituem um importante problema de saúde pública. A vacinação de animais contra Salmonella é uma estratégia para prevenir essas infecções e reduzir o risco para a saúde pública. As vacinas vivas atenuadas de Salmonella enterica podem conferir proteção contra a salmonelose, induzindo respostas imunológicas mediadas por células e em mucosas. Este estudo avaliou uma vacina viva e atenuada de Salmonella enterica Typhimurium (ST) em frangos de corte contra um desafio heterólogo com Salmonella Heidelberg (SH), avaliando a quantificação de Salmonella, infiltração de células imunes e a expressão de genes de citocinas no ceco. Os tratamentos foram: T1, não vacinado, não desafiado; T2, não vacinado, desafiado com SH; T3, ST-vacinado, desafiado com SH. Aos 28 dias de idade, o grupo vacinado com ST apresentou significativa redução de SH no papo (P<0,01) e no ceco (P = 0,021) comparado ao grupo T2-não vacinado SH-desafiado, sem alterações significativas na dinâmica celular de macrófagos, T CD4+ ou T CD8+ (P˃0,05) durante o mesmo período. A vacinação por aerossol no primeiro dia promoveu maior expressão de IL-12 no fígado (P<0,05), maior expressão de IL-10 e células T CD8+ no íleo, 16 horas após o alojamento. Após o reforço de imunização oral ao 13º dia, o grupo vacinado apresentou maior expressão de macrófagos e células T CD4+ no fígado (P<0,05) do que o grupo controle. Duas doses de uma vacina viva atenuada de ST promoveram um efeito de proteção cruzada parcial contra o desafio da cepa de Salmonella Heidelberg cepa UFPR1 em frangos de corte.(AU)

Salmonella typhimurium vaccine to control a brazilian Salmonella heidelberg strain in broiler chickens / Vacina de Salmonella typhimurium para controlar cepa brasileira de Salmonella heidelberg em frangos de corte

Foodborne Salmonella infections in humans, which results from the consumption of contaminated poultry meat and eggs, are a major public health concern. Vaccination of animals against Salmonella is one strategy to prevent these infections and reduce the risks to public health. Live attenuated Salmonella enterica vaccines can confer protection against salmonellosis by inducing both cell-mediated and mucosal immune responses. This study assessed a live, attenuated Salmonella enterica Typhimurium (ST) vaccine in broiler chickens against a heterologous challenge with Salmonella Heidelberg (SH) by evaluating bacterial quantification, immune cells infiltration, and cytokine gene expression in the cecum. The treatments were: T1, non-vaccinated, non-challenged; T2, non-vaccinated, SH-challenged; T3, ST-vaccinated and SH-challenged. At 28 days of age, the ST-vaccinated group had significantly recovered reduction of SH in the crop (P<0,01) and cecum (P = 0,021) compared to the non-vaccinated SH-challenged group, with no significant changes (P˃0,05) in macrophages, T CD4+, or T CD8+ cells dynamics during the same period. Aerosol vaccination on the first day promoted greater interleukin-12 expression in the liver (P<0,05) and interleukin-10 expression and T CD8+ cells in the ileum 16 hours after housing. After prime-boosted oral immunization on the 13th day, the vaccinated group had greater expression of macrophages and T CD4+ cells in the liver (P<0,05) than the control group. Two doses of a live ST-attenuated vaccine promoted a partial cross-protective effect against SH strain UFPR1 challenge in broilers.

Infecções por Salmonella transmitidas por alimentos como consumo de carne de frango e ovos contaminados em seres humanos constituem um importante problema de saúde pública. A vacinação de animais contra Salmonella é uma estratégia para prevenir essas infecções e reduzir o risco para a saúde pública. As vacinas vivas atenuadas de Salmonella enterica podem conferir proteção contra a salmonelose, induzindo respostas imunológicas mediadas por células e em mucosas. Este estudo avaliou uma vacina viva e atenuada de Salmonella enterica Typhimurium (ST) em frangos de corte contra um desafio heterólogo com Salmonella Heidelberg (SH), avaliando a quantificação de Salmonella, infiltração de células imunes e a expressão de genes de citocinas no ceco. Os tratamentos foram: T1, não vacinado, não desafiado; T2, não vacinado, desafiado com SH; T3, ST-vacinado, desafiado com SH. Aos 28 dias de idade, o grupo vacinado com ST apresentou significativa redução de SH no papo (P<0,01) e no ceco (P = 0,021) comparado ao grupo T2-não vacinado SH-desafiado, sem alterações significativas na dinâmica celular de macrófagos, T CD4+ ou T CD8+ (P˃0,05) durante o mesmo período. A vacinação por aerossol no primeiro dia promoveu maior expressão de IL-12 no fígado (P<0,05), maior expressão de IL-10 e células T CD8+ no íleo, 16 horas após o alojamento. Após o reforço de imunização oral ao 13º dia, o grupo vacinado apresentou maior expressão de macrófagos e células T CD4+ no fígado (P<0,05) do que o grupo controle. Duas doses de uma vacina viva atenuada de ST promoveram um efeito de proteção cruzada parcial contra o desafio da cepa de Salmonella Heidelberg cepa UFPR1 em frangos de corte.

Histopathology and serology reaction to an immune complex infectious bursal disease vaccine (V877 strain) in SPF and commercial birds / Reação histopatológica e sorológica a uma vacina de imunocomplexo contra gumboro (cepa V877) em aves SPF e comerciais

The purpose of this study was to investigate the effect of a new infectious bursal disease (IBD) immune complex vaccine on immune system response in both specific pathogen-free (SPF) and commercial birds. Evaluation of response to the vaccination in the two experiments was done by histopathological examination and serology. The results of this study have shown that immune complex vaccine with the V877 strain is quite safe in White Leghorn SPF birds in which there has been no participation of maternal antibodies. In commercial birds was also observed that the immune complex vaccine with the V877 strain acted synergistically with different levels of passive antibodies and the vaccine virus began to replicate as passive immunity decreased to provide the animal active immunological response.(AU)

O objetivo desse estudo foi investigar o efeito de uma nova vacina de imunocomplexo contra a doença de Gumboro sobre o sistema imune de aves SPF e comerciais. A avaliação da resposta à vacinação foi realizada por meio de exame histopatológico e sorologia. Os resultados desse estudo demonstraram que a vacina de imunocomplexo com cepa V877 contra Gumboro é muito segura mesmo em aves SPF da linhagem White Leghorn nas quais não existia a participação de imunidade materna. Em aves comerciais também foi demonstrado que a vacina de imunocomplexo com a cepa V877 atuou sinergicamente com diferentes níveis de anticorpos passivos maternais, iniciando a replicação do vírus vacinal a partir do momento que a imunidade passiva diminui, para promover uma resposta imunológica ativa.(AU)

Histopathology and serology reaction to an immune complex infectious bursal disease vaccine (V877 strain) in SPF and commercial birds / Reação histopatológica e sorológica a uma vacina de imunocomplexo contra gumboro (cepa V877) em aves SPF e comerciais

The purpose of this study was to investigate the effect of a new infectious bursal disease (IBD) immune complex vaccine on immune system response in both specific pathogen-free (SPF) and commercial birds. Evaluation of response to the vaccination in the two experiments was done by histopathological examination and serology. The results of this study have shown that immune complex vaccine with the V877 strain is quite safe in White Leghorn SPF birds in which there has been no participation of maternal antibodies. In commercial birds was also observed that the immune complex vaccine with the V877 strain acted synergistically with different levels of passive antibodies and the vaccine virus began to replicate as passive immunity decreased to provide the animal active immunological response.

O objetivo desse estudo foi investigar o efeito de uma nova vacina de imunocomplexo contra a doença de Gumboro sobre o sistema imune de aves SPF e comerciais. A avaliação da resposta à vacinação foi realizada por meio de exame histopatológico e sorologia. Os resultados desse estudo demonstraram que a vacina de imunocomplexo com cepa V877 contra Gumboro é muito segura mesmo em aves SPF da linhagem White Leghorn nas quais não existia a participação de imunidade materna. Em aves comerciais também foi demonstrado que a vacina de imunocomplexo com a cepa V877 atuou sinergicamente com diferentes níveis de anticorpos passivos maternais, iniciando a replicação do vírus vacinal a partir do momento que a imunidade passiva diminui, para promover uma resposta imunológica ativa.

Properties of proteases from milk somatic cells and blood leukocytes.

Proteolytic activity of proteases associated with somatic cells isolated from high SCC milk and proteases associated with leukocytes isolated from bovine blood was assayed at pH 6.6 and 5.2 in a model system consisting of a beta-casein (.96%) substrate in Jenness/Koops buffer. Intact beta-casein and casein proteolysis products were measured by densitometric analysis of SDS-PAGE gels. Relative proteolytic activity was expressed as percentage degradation of beta-casein after 24 h at 37 degrees C per 1 x 10(6) cells/ml. Proteolytic activity associated with somatic cells isolated from bovine milk was 27.5 and 13.6% at pH 6.6 and 5.2, respectively. Proteolytic activity associated with leukocytes isolated from bovine blood was 16.0 and 8.4% at pH 6.6 and 5.2, respectively. Proteolytic activity at pH 6.6 was significantly higher for the somatic cells isolated from milk than for leukocytes isolated from blood. The reason for the difference in proteolytic activity of leukocytes isolated from blood of a healthy cow versus somatic cells isolated from milk produced by a cow with mastitis is not known. Further work is needed to determine whether the difference may be caused by a higher proportion of activated macrophages in somatic cells isolated from milk produced by cows with mastitis than in the leukocytes isolated from blood of healthy cows.

Preliminary investigation of the properties of somatic cell proteases.

Effect of the plasmin inhibitor 6-amino-n-hexanoic acid on somatic cell proteases (equivalent to 2.3 X 10(6) cells/ml) was determined using a model system of casein micelles dispersed in Jenness/Koops buffer (1.5% wt/vol). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis was used to quantitate casein. There was no effect of 120 mM 6-amino-n-hexanoic acid on casein proteolysis by somatic cell proteases. Molecular weights of casein proteolysis products produced by somatic cell proteases were different from those produced by plasmin. Quantitative and qualitative analyses of pasteurized mastitic milk by SDS-PAGE indicated that a portion of the somatic cell proteolytic activity survived pasteurization. Because 6-amino-n-hexanoic acid does not inhibit somatic cell proteases, it can be used to establish the relative contribution of somatic cell proteases and plasmin to total proteolytic activity in mastitic milk.

Effect of mastitis on proteolytic activity in bovine milk.

Proteolytic activity of milk was studied before, during, and after experimental-induced mastitis. An inoculum of Streptococcus agalactiae was infused into one quarter of each udder of six cows to elicit an infection. Bacteriological cultures and SCC of milk were used to monitor infection status. Sodium dodecyl sulfate-PAGE was used to measure proteolytic activity of milk. Inhibitor 6-amino-n-hexanoic acid was used to determine the relative proportion of plasmin and nonplasmin proteolytic activity of milk. Somatic cell count, total milk proteolytic activity, and nonplasmin proteolytic activity were higher in infected quarters than in quarters preinfection. After elimination of infections, SCC and nonplasmin proteolytic activity decreased to preinfection amounts. Total proteolytic activity of milk decreased after infections were cured but remained significantly higher than preinfection activity. This postinfection proteolytic activity in milk may be due to an increase in milk plasmin activity. Our data suggest that detrimental effects of mastitis on milk quality can continue after infection has been eliminated and milk SCC have returned to low values.

Variability in true protein, casein, nonprotein nitrogen, and proteolysis in high and low somatic cell milks.

Monthly variation in milk protein (total nitrogen X 6.38) and milk fat was determined for 115 farms over 2 yr. Yearly average milk protein and fat tests in each year were 3.16 and 3.62%, respectively. The mean regression coefficient for milk protein with respect to milk fat was .47 for the entire period. Twenty-four farms were selected and grouped high or low based on their previous 2-yr somatic cell history. Monthly milk samples for each farm were tested for direct microscopic somatic cell count, total nitrogen, noncasein nitrogen, and nonprotein nitrogen. No differences in monthly nonprotein nitrogen, true protein, and casein were found between groups. Casein as a percent of total nitrogen was significantly higher for the low somatic group for seven of the 12 mo studied but was significantly higher for 9 mo when expressed as a percent of true protein. The average increase in tyrosine value for incubated preserved milk was significantly higher for the high somatic cell milk, indicating higher proteolytic activity in high somatic cell milk. Electrophoretic analysis of high and low somatic cell milk indicated that there was substantial proteolytic breakdown of alpha S-casein and beta-casein by proteases associated with elevated somatic cell counts.

SALMONELLA TYPHIMURIUM VACCINE TO CONTROL A BRAZILIAN SALMONELLA HEIDELBERG STRAIN IN BROILER CHICKENS

Foodborne Salmonella infections in humans, which results from the consumption of contaminated poultry meat and eggs, are a major public health concern. Vaccination of animals against Salmonella is one strategy to prevent these infections and reduce the risks to public health. Live attenuated Salmonella enterica vaccines can confer protection against salmonellosis by inducing both cell-mediated and mucosal immune responses. This study assessed a live, attenuated Salmonella enterica Typhimurium (ST) vaccine in broiler chickens against a heterologous challenge with Salmonella Heidelberg (SH) by evaluating bacterial quantification, immune cells infiltration, and cytokine gene expression in the cecum. The treatments were: T1, non-vaccinated, non-challenged; T2, non-vaccinated, SH-challenged; T3, ST-vaccinated and SH-challenged. At 28 days of age, the ST-vaccinated group had significantly recovered reduction of SH in the crop (P

HISTOPATHOLOGY AND SEROLOGY REACTION TO AN IMMUNE COMPLEX INFECTIOUS BURSAL DISEASE VACCINE (V877 STRAIN) IN SPF AND COMMERCIAL BIRDS

The purpose of this study was to investigate the effect of a new infectious bursal disease (IBD) immune complex vaccine on immune system response in both specific pathogen-free (SPF) and commercial birds. Evaluation of response to the vaccination in the two experiments was done by histopathological examination and serology. The results of this study have shown that immune complex vaccine with the V877 strain is quite safe in White Leghorn SPF birds in which there has been no participation of maternal antibodies. In commercial birds was also observed that the immune complex vaccine with the V877 strain acted synergistically with different levels of passive antibodies and the vaccine virus began to replicate as passive immunity decreased to provide the animal active immunological response.