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1.
J Dairy Sci ; 103(1): 915-921, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31704014

RESUMO

Streptococcus uberis is an important causative agent for clinical and subclinical mastitis in dairy cattle. The aim of this study was to develop 2 multiplex PCR assays (mPCR) for the simultaneous detection of virulence factors and housekeeping genes for use when investigating the genetic variability and distribution of Strep. uberis virulence factors. The tuf, cpn60, pauA, sodA, sua, oppF, and gapC genes were grouped in assay 1 (mPCR1) and the hasA, hasB, and hasC genes were included in assay 2 (mPCR2). The detection limits were 11.8 pg and 5.9 pg of DNA for mPCR1 and mPCR2, respectively. The 2 mPCR assays were validated with 56 Strep. uberis strains isolated from mastitis milk samples collected from different bovine herds in northern Italy. Results revealed that gapC and oppF were detected in 98.2% of the strains, whereas sua and hasC genes were detected in 94.6 and 89.2% of the strains, respectively. The most common pattern was gapC+, oppF+, cpn60+, sua+, sodA+, pauA+, tuf+, hasA+, hasB+, and hasC+, which appeared in 59% of the strains analyzed. The molecular assays developed in the present study represent a powerful tool for the evaluation of virulence pattern distribution in Strep. uberis strains associated with intramammary infections.


Assuntos
Mastite Bovina/microbiologia , Infecções Estreptocócicas/veterinária , Streptococcus/isolamento & purificação , Animais , Proteínas de Bactérias/genética , Bovinos , Feminino , Itália/epidemiologia , Mastite Bovina/epidemiologia , Reação em Cadeia da Polimerase Multiplex , Reação em Cadeia da Polimerase/métodos , Infecções Estreptocócicas/microbiologia , Streptococcus/genética , Virulência , Fatores de Virulência/genética
2.
Vet Microbiol ; 237: 108385, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31585645

RESUMO

Streptococcus uberis is an important bovine mastitis pathogen, but not all isolates have equal capacity to cause disease. The aims of this study were to identify possible virulence-associated genes that could be used to identify isolates with enhanced virulence. DNA from a pool of putative commensals was subtracted from a clinical pool resulting in a set of DNA sequences (probes) that were enriched in the clinical mastitis group. The probes were hybridised with DNA from a collection 29 isolates from cases of clinical mastitis and isolates not associated with disease. Hybridization revealed five major clusters. The first cluster (7 isolates) consisted almost entirely of commensals, while the second (7 isolates) was mixed. The remaining three clusters contained 15 S. uberis isolates from cows with clinical mastitis. Twenty-six probes were selected for sequencing based on principal component analysis (PCA) or their presence mainly in clinical isolates. PCA identified five probes with clear differences in intensity between signals from clinical isolates and commensals; these probes could represent novel virulence determinants. Manual inspection of arrays identified genes prominent among clinical isolates that specify carbohydrate and lipid metabolism (possible role in the growth or survival of S. uberis in milk) and genes specifying hypothetical proteins, possibly novel virulence factors. The common occurrence, among clinical isolates, of probes having homology with transposases and insertion sequences suggests recent acquisition of factors that could be associated with virulence. These results suggest the existence of a subset of S. uberis with enhanced virulence, due possession of virulence-associated gene sequences.


Assuntos
Mastite Bovina/microbiologia , Infecções Estreptocócicas/veterinária , Streptococcus/patogenicidade , Técnica de Subtração , Animais , Bovinos , Clonagem Molecular , DNA Bacteriano , Feminino , Análise de Componente Principal , Infecções Estreptocócicas/microbiologia , Streptococcus/genética , Virulência
3.
J Fish Dis ; 42(12): 1657-1666, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31591734

RESUMO

Streptococcus iniae is one of the most serious aquatic pathogens, causing significant economic losses in marine and freshwater species, including Asian seabass (Lates calcarifer). Controlling this gram-positive bacterial pathogen has been an issue in aquaculture systems, due to the combined effects of aquaculture intensification and climatic impacts. To date, there have not been any genetic parameter estimates for S. iniae resistance in Asian seabass. The main aim of this study was to examine genetic variation in S. iniae resistance and its genetic correlations with growth and cannibalism in Asian seabass families produced from a breeding programme for high growth in 2016 and 2017. The study included a total of 5,835 individual fish that were offspring of 41 sires and 60 dams (31 half-sib and 34 full-sib families). The experimental fish were challenged by intraperitoneal injection with a volume containing 105  CFU (colony-forming unit)/fish. Resistance to S. iniae was measured as survival rate at 6 hr, 3, 5, 7, 10 and 15 days post-challenge test. There were significant variations in S. iniae resistance among families at different observation periods (ranging from 24.4% to 80%). Restricted maximum-likelihood method and mixed model analysis were applied to estimate heritability for S. iniae resistance. The heritability for S. iniae resistance ranged from 7% to 18% across different statistical models used. The common full-sib effects accounted for 0.1%-2% of the total variation in resistance to S. iniae. Genetic correlations of the S. iniae resistance at 6 hr and 3 days with later post-challenge test periods were low to moderate. However, these estimates for S. iniae resistance between successive measurement times (5, 7, 10 and 15 days) were high and close to 1. The genetic correlations of resistance with body weights at 180, 270 and 360 days post-hatch were not significant as well with cannibalism. It is concluded that there is substantial additive genetic variation in resistance to S. iniae, suggesting there is potential for genetic improvement of Asian seabass for resistance to S. iniae through selective breeding.


Assuntos
Resistência à Doença/genética , Doenças dos Peixes/genética , Perciformes/genética , Infecções Estreptocócicas/veterinária , Animais , Aquicultura , Canibalismo , Feminino , Doenças dos Peixes/microbiologia , Masculino , Modelos Estatísticos , Perciformes/microbiologia , Fenótipo , Infecções Estreptocócicas/genética , Infecções Estreptocócicas/microbiologia , Streptococcus iniae
4.
J Dairy Sci ; 102(12): 11384-11400, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31606215

RESUMO

Objectives of this study were to (1) describe the intramammary infection (IMI) prevalence and pathogen profiles in quarters of cows approaching dry-off in US dairy herds, (2) compare IMI prevalence in quarters of cows exposed to different bedding material types, and (3) identify associations between bedding bacteria count and IMI in cows approaching dry-off. Eighty herds using 1 of 4 common bedding materials (manure solids, organic non-manure, new sand, and recycled sand) were recruited in a multi-site cross-sectional study. Each herd was visited twice for sampling. At each visit, aseptic quarter-milk samples were collected from 20 cows approaching dry-off (>180 d pregnant). Samples of unused and used bedding were also collected. Aerobic culture was used to determine the IMI status of 10,448 quarters and to enumerate counts (log10 cfu/mL) of all bacteria, Staphylococcus spp., Streptococcus spp. and Streptococcus-like organisms (SSLO), coliforms, Klebsiella spp., noncoliform gram-negatives, Bacillus spp., and Prototheca spp. in unused (n = 148) and used (n = 150) bedding. The association between bedding bacteria count and IMI was determined using multivariable logistic regression with mixed effects. Quarter-level prevalence of IMI was 21.1%, which was primarily caused by non-aureus Staphylococcus spp. (11.4%) and SSLO (5.6%). Only modest differences in IMI prevalence were observed between the 4 common bedding material types. Counts of all bacteria in unused bedding was positively associated with odds of IMI caused by any pathogen [ALL-IMI; odds ratio (OR) = 1.08]. A positive association was also observed for counts of SSLO in unused bedding and SSLO-IMI (OR = 1.09). These patterns of association were generally consistent across the 4 common bedding materials. In contrast, the association between counts of all bacteria in used bedding and ALL-IMI varied by bedding type, with positive associations observed in quarters exposed to manure solids (OR = 2.29) and organic non-manure (OR = 1.51) and a negative association in quarters exposed to new sand (OR = 0.47). Findings from this study suggest that quarter-level IMI prevalence in late-lactation cows is low in US dairy herds. Furthermore, bedding material type may not be an important risk factor for IMI in late lactation. Higher levels of bacteria in bedding may increase IMI prevalence at dry-off in general, but this relationship is likely to vary according to bedding material type.


Assuntos
Infecções por Klebsiella/veterinária , Mastite Bovina/microbiologia , Leite/microbiologia , Infecções Estafilocócicas/veterinária , Infecções Estreptocócicas/veterinária , Animais , Carga Bacteriana/veterinária , Roupas de Cama, Mesa e Banho/microbiologia , Roupas de Cama, Mesa e Banho/veterinária , Bovinos , Estudos Transversais , Feminino , Klebsiella/isolamento & purificação , Infecções por Klebsiella/epidemiologia , Infecções por Klebsiella/microbiologia , Lactação , Modelos Logísticos , Glândulas Mamárias Animais/microbiologia , Esterco/microbiologia , Mastite Bovina/epidemiologia , Prevalência , Fatores de Risco , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus/isolamento & purificação , Infecções Estreptocócicas/epidemiologia , Infecções Estreptocócicas/microbiologia , Streptococcus/isolamento & purificação
5.
J Dairy Sci ; 102(12): 11401-11413, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31606221

RESUMO

Because cloth udder towels (CUT) may function as a fomite for mastitis-causing pathogens, most udder health laboratories offer towel culture services as a tool to monitor towel hygiene. However, no studies have investigated if an association exists between bacteria levels in CUT and udder health outcomes. The objectives of this cross-sectional study were to (1) describe associations between herd-level measures of towel bacteria count (ToBC) and quarter-level intramammary infection (IMI) status in late-lactation cows, (2) establish pathogen-specific target levels of bacteria in CUT to aid the interpretation of towel culture reports, and (3) identify laundering-related risk factors for high ToBC. The study was conducted in 67 herds from 10 dairy states in the United States that used CUT. These 67 herds were originally recruited as part of a larger (80 herd) cross-sectional study of bedding management. Each herd was visited once during December 2017 to April 2018 and quarter-milk samples (n = 4,656) were collected from late-gestation (>180 d pregnant) cows (n = 1,313). Two recently laundered CUT were collected and a questionnaire was used to collect information about pre-milking teat preparation and CUT management practices. Quarter-level IMI status was determined using standard bacteriologic methods. In addition, colony-forming units of all bacteria (total bacteria), Staphylococcus spp., Streptococcus spp. or Streptococcus-like organisms (SSLO), coliforms, noncoliform gram-negatives, and Bacillus spp. were determined for each pair of CUT (log10 cfu/cm2). The association between ToBC and IMI was determined using multivariable logistic regression with mixed effects. After dichotomizing ToBC into high and low categories, associations between towel management practices and ToBC category were determined using unconditional logistic regression. The quarter-level prevalence of IMI was 19.6%, which was predominantly caused by non-aureus Staphylococcus spp. (NAS; 10.2%) and SSLO (5.1%). The predominant bacteria in CUT were Bacillus spp. (median = 3.13 log10 cfu/cm2). Total bacteria count was not associated with odds of IMI (odds ratio = 1.06), likely due to the predominance of Bacillus spp. in CUT and low number of IMI caused by Bacillus spp. In contrast, counts of Staphylococcus spp. and SSLO were positively associated with odds of IMI caused by NAS (odds ratio = 1.33) and SSLO (odds ratio = 1.45), respectively. Of 12 CUT management practices evaluated, only the failure to use a dryer was identified as a clear predictor of risk for a high ToBC (risk ratio of high coliform count = 8.17). Our study findings suggest that CUT may act as a fomite for NAS and SSLO. We recommend that herds aim to keep counts of Staphylococcus spp. and SSLO in CUT below 32 cfu/cm2 (or 5 cfu/in2), and that laundered towels be completely dried in a hot air dryer.


Assuntos
Infecções por Klebsiella/veterinária , Mastite Bovina/microbiologia , Leite/microbiologia , Infecções Estafilocócicas/veterinária , Infecções Estreptocócicas/veterinária , Animais , Carga Bacteriana/veterinária , Bovinos , Estudos Transversais , Feminino , Klebsiella/isolamento & purificação , Infecções por Klebsiella/epidemiologia , Infecções por Klebsiella/microbiologia , Lactação , Modelos Logísticos , Glândulas Mamárias Animais/microbiologia , Esterco/microbiologia , Mastite Bovina/epidemiologia , Gravidez , Prevalência , Fatores de Risco , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus/isolamento & purificação , Infecções Estreptocócicas/epidemiologia , Infecções Estreptocócicas/microbiologia , Streptococcus/isolamento & purificação
6.
Fish Shellfish Immunol ; 94: 407-416, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31521784

RESUMO

The aims of this study were to investigate the antibacterial, immunostimulatory and antioxidant properties of different derivatives of Oliveria decumbens, in vitro and in vivo. The GC-MS spectrometry analysis showed γ-terpinene as the most frequent compound in essential oil, whereas carvacrol and thymol were the most common ones in aromatic water. Plant essential oil and hydroethanolic extract showed a positive in vitro bactericidal activity against Streptococcus iniae as evaluated by disc diffusion, minimum inhibitory concentration and minimum bactericidal concentration methods. Also, in vivo resistance against S. iniae and immune and antioxidant responses of Nile tilapia (Oreochromis niloticus) were assayed after 60 days treatment with O. decumbens derivatives. Plant hydroethanolic extract and essential oil and their 1:1 combination were added to diet at 0 (negative control), 0.01, 0.1 and 1% (w:w). The plant aromatic water at doses of 0.0312, 0.0625 and 0.1250% were also used as bath treatment. The results showed that aromatic water at lowest dose was more effective than other treatments in increment of fish resistance against S. iniae (7.14% mortality in comparison with 50% mortalities in control fish) and modulation of post-challenge respiratory burst activity. The bactericidal activity and biochemical contents of skin mucus did not change significantly among treatments. The levels of superoxide dismutase and catalase antioxidant enzymes activities in spleen tissue were significantly higher in treatments received extract, essential oils and their combination in comparison to other groups, while treatments did not affect peroxidase level. In conclusion, administration of different derivatives of Oliveria decumbens showed remarkable antibacterial activity against streptococcosis and enhanced antioxidant status and post-challenge immunity in Nile tilapia.


Assuntos
Adjuvantes Imunológicos/farmacologia , Antibacterianos/farmacologia , Apiaceae/química , Ciclídeos/imunologia , Óleos Voláteis/farmacologia , Extratos Vegetais/farmacologia , Streptococcus iniae/efeitos dos fármacos , Adjuvantes Imunológicos/química , Ração Animal/análise , Animais , Antibacterianos/química , Antioxidantes/metabolismo , Dieta/veterinária , Suplementos Nutricionais/análise , Resistência à Doença/imunologia , Relação Dose-Resposta a Droga , Doenças dos Peixes/imunologia , Imunidade nas Mucosas/efeitos dos fármacos , Óleos Voláteis/química , Extratos Vegetais/química , Soro/efeitos dos fármacos , Soro/imunologia , Infecções Estreptocócicas/imunologia , Infecções Estreptocócicas/veterinária , Streptococcus iniae/fisiologia
7.
Fish Shellfish Immunol ; 94: 889-895, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31546039

RESUMO

Short-term feed deprivation or fasting is commonly experienced by aquaculture fish species and may be caused by seasonal variations, production strategies, or diseases. To assess the effects of fasting on the resistance of Nile tilapia to Streptococcus agalactiae infection, vaccinated and unvaccinated fish were fasted for zero, one, three, and seven days prior to infection. The cortisol levels of both vaccinated and unvaccinated fish first decreased and then increased significantly as fasting time increased. Liver glycogen, triglycerides, and total cholesterol decreased significantly after seven days of fasting, but glucose content did not vary significantly between fish fasted for three and seven days. Hexokinase (HK) and pyruvate kinase (PK) activity levels were lowest after seven days of fasting, while phosphoenolpyruvate carboxykinase (PEPCK) activity levels varied in opposition to those of HK and PK. Serum superoxide dismutase (SOD) and catalase (CAT) activity levels first increased and then decreased as fasting time increased; SOD activity was highest after three days of fasting. Interleukin-1beta (IL-1ß) and IL-6 mRNA expression levels first increased and then decreased significantly, peaking after three days of fasting. However, suppressor of cytokine signaling-1 (SOCS-1) mRNA expression levels were in opposition to those of IL-1ß and IL-6. Specific antibody levels did not vary significantly among unvaccinated fish fasted for different periods. Although specific antibody level first increased and then decreased in the vaccinated fish as fasting duration increased, there were no significant differences in the survival rates of fasted vaccinated fish after challenge with S. agalactiae. The final survival rates of vaccinated fish fasted for zero, one, three, and seven days were 86.67 ±â€¯5.44%, 80.00 ±â€¯3.14%, 88.89 ±â€¯6.28%, and 84.44 ±â€¯8.32%, respectively. Among the unvaccinated fish, the survival rate was highest (35.56 ±â€¯3.14%) in the fish fasted for three days and lowest (6.67 ±â€¯3.14%) in the fish fasted for seven days. Therefore, our results indicated that short-term fasting (three days) prior to an infection might increase the resistance of unvaccinated Nile tilapia to S. agalactiae.


Assuntos
Ciclídeos/imunologia , Resistência à Doença/fisiologia , Doenças dos Peixes/imunologia , Privação de Alimentos/fisiologia , Animais , Masculino , Distribuição Aleatória , Infecções Estreptocócicas/imunologia , Infecções Estreptocócicas/veterinária , Streptococcus agalactiae/fisiologia
8.
J Dairy Sci ; 102(11): 10587-10598, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31477304

RESUMO

In 2 epidemiological studies, we evaluated the effect of mastitis induced by gram-positive Streptococcus and gram-negative Escherichia coli on impaired reproductive performance in lactating Holstein cows. In the first study, 52,202 cows from 178 dairy farms throughout Israel were divided into groups based on infection before first artificial insemination (AI) with Streptococcus or E. coli, 3 groups with elevated somatic cell count (SCC) without infection by those pathogens [low SCC (200-400) × 103 cell/mL; medium SCC (401-1,000) × 103 cell/mL; high SCC, >1,000 × 103 cell/mL], and uninfected controls. Pregnancy per first AI (P/1stAI) and pregnancy rate at 300 d in milk (PREG 300) were analyzed by the GLIMMIX procedure (SAS); number of AI per pregnancy (AI/P), days open, and rest days (calving to first AI) were analyzed by the MIXED procedure (SAS Institute Inc., Cary, NC). Values of P/1stAI were similarly low for Streptococcus and E. coli (27-28%) versus 42% in controls; PREG 300 was lower for Streptococcus (76%) than for E. coli (79%) versus 88% for uninfected controls and a mean 83% for the elevated SCC groups. Days open and number of AI/P were higher than in controls and similar in Streptococcus and E. coli groups. The second study included 778 cows on 6 dairy farms; the cows were infected before first AI by Streptococcus or E. coli or uninfected. Resumption of cyclicity was determined by an automated activity-monitoring system, and data were sorted by time of infection before or after cyclicity resumed. The Streptococcus group had lower P/1stAI before and after cyclicity (26 and 27%, respectively) than the E. coli group (31 and 34%, respectively) and uninfected controls (42%). Notably, PREG 300 in the Streptococcus group before (73%) and after (67%) cyclicity was much lower than for the E. coli group (85 and 93%, respectively) and the controls (95%). A marked rise in day of cyclicity resumption (∼80 d) was observed in cows that were infected early on. Number of AI/P was higher in the mastitic groups than in uninfected controls. Uterine disease postpartum, although more prevalent among Streptococcus cows, did not substantially alter the larger reduction in P/1stAI and PREG 300 in Streptococcus versus E. coli cows. Thus, long-term Streptococcus-induced mastitis disrupted fertility more than short-term acute E. coli-induced mastitis, resulting in a much higher percentage of Streptococcus cows in late lactation that did not conceive due to reproduction failure.


Assuntos
Infecções por Escherichia coli/veterinária , Mastite Bovina/fisiopatologia , Reprodução , Infecções Estreptocócicas/veterinária , Animais , Bovinos , Escherichia coli , Infecções por Escherichia coli/fisiopatologia , Feminino , Fertilidade , Inseminação Artificial/veterinária , Israel , Lactação , Mastite Bovina/microbiologia , Leite , Gravidez , Taxa de Gravidez , Infecções Estreptocócicas/fisiopatologia , Streptococcus
9.
Fish Shellfish Immunol ; 94: 280-287, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31499203

RESUMO

As recently applicable, there are few studies on the impact of using nano-selenium (nano-Se) on varied fish species. Where nothing reachable focused on its impact on tilapias so, the present analysis evaluated the efficacy of using nano-Se in tilapias on immune response, antioxidant defense compared by conventional Se form. 480 O. niloticus fingerlings were haphazardly grouped firstly into three groups with four replicates of each. The control one (CT) was fed on a basal diet. The second and third one supplemented with 0.7 mg/kg-1 Se and nano-Se respectively for ten weeks. At the start day of the ninth week, two replicates from each group were injected by Streptococcus iniae where, the remaining replicates stand without challenge. Enhancement of growth performance measurements were noted in nano-Se compared to Se or CT groups. Existed anemia in S. iniae tilapias became alleviated by using nano-Se that also, improves the alteration of leucogram induced by challenge. Elevation of aminotransferases, alkaline phosphatase, lactate dehydrogenase (ALT, AST, ALP and LDH) and creatinine in Se and CT challenged replicates that seemed nearly normal by using nano-Se. Usage of nano-Se showed more powerful antioxidant activities than Se. There were an expansion of immunoglobulin M, lysozymes, glutathione peroxidase, nitric oxide, superoxide dismutase and catalase (IgM, LYZ, GPx, NO, SOD, CAT) and their related gene expression in nano-Se with contrast in Se or CT challenged groups. Nile tilapias challenged by S. iniae disclosed substantial expansion in the percentage of mortality in CT challenged fish (93.33%), followed by the group supplemented with Se (73.33%), whereas the lowermost one at fish supplemented by nano-Se (26.66%). The mortalities have been stopped from the 5th, 12th and 14th days in, nano-Se, Se and CT respectively. It can be concluded that using of Se 0.7 mg/kg-1induce immunosuppressive, antioxidant, liver and kidneys negative impact on tilapias where the same dose from nano-Se was more potent immunomodulating and antioxidant. Also it is attend in counteracting the serious impact induced by S. iniae challenge.


Assuntos
Ciclídeos/imunologia , Resistência à Doença , Doenças dos Peixes/imunologia , Micronutrientes/metabolismo , Nanopartículas/metabolismo , Selênio/metabolismo , Ração Animal/análise , Animais , Ciclídeos/crescimento & desenvolvimento , Ciclídeos/metabolismo , Dieta/veterinária , Suplementos Nutricionais/análise , Micronutrientes/administração & dosagem , Nanopartículas/administração & dosagem , Selênio/administração & dosagem , Infecções Estreptocócicas/imunologia , Infecções Estreptocócicas/veterinária , Streptococcus iniae/fisiologia
10.
Fish Shellfish Immunol ; 94: 355-372, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31533079

RESUMO

Streptococcus agalactiae is a major aquaculture pathogen infecting various saltwater and freshwater fish. To better understand the mechanism of the immune responses to S. agalactiae in wildtype zebrafish, the transcriptomic profiles of two organs containing mucosal-associated lymphoid tissues from S. agalactiae-infected and non-infected groups were obtained using RNA-seq techniques. In the intestines, 6735 and 12908 differently expressed genes (DEGs) were identified at 24 hpi and 48 hpi, respectively. Among 66 and 116 significantly enriched pathways, 15 and 21 pathways were involved in immune system or signal transduction at 24 hpi and 48 hpi, respectively. A number of genes involved in Toll-like receptor signaling pathway, RIG-I-like receptor signaling pathway, NOD-like receptor signaling pathway, T cell receptor signaling pathway, B cell receptor signaling pathway, Antigen processing and presentation, NF-kappa B signaling pathway and PI3K-Akt signaling pathway were significantly downregulated. In the skins, 3113 and 4467 DEGs were identified at 24 hpi and 48 hpi, respectively. Among 24 and 56 significantly enriched pathways, 4 and 13 pathways were involved in immune system or signal transduction at 24 hpi and 48 hpi, respectively. More immune-related signaling pathways including Leukocyte transendothelial migration, Cytokine-cytokine receptor interaction, PI3K-Akt signaling pathway, IL-17 signaling pathway, MAPK signaling pathway, TNF signaling pathway, Complement and coagulation cascades, Hematopoietic cell lineage and Jak-STAT signaling pathway were differently enriched for upregulated DEGs at 48 hpi, which were completely different from that in the intestines. Furthmore, comparative transcriptome analysis revealed that the downregulated 1618 genes and upregulated 1622 genes existed both at 24 hpi and 48 hpi for the intestine samples. In the skins, the downregulated 672 genes and upregulated 428 genes existed both at 24 hpi and 48 hpi. Three pathways related to immune processes were significantly enriched for downregulated DEGs both in the intestines and skins collected at 24 hpi and 48 hpi, which included Antigen processing and presentation, Intestinal immune network for IgA production and Hematopoietic cell lineage. Interaction network analysis of DEGs identified the main DEGs in the sub-network of complement and coagulation cascades both in the intestines and skins. Twenty of DEGs involved in complement and coagulation cascades were further validated by Real-time quantitative PCR. Altogether, the results obtained in this study will provide insight into the immune response of zebrafish against S. agalactiae XQ-1 infection in fatal conditions, and reveal the discrepant expression pattern of complement and coagulation cascades in the intestines and skins.


Assuntos
Imunidade Adaptativa/genética , Doenças dos Peixes/imunologia , Imunidade Inata/genética , Transcriptoma/genética , Transcriptoma/imunologia , Peixe-Zebra/genética , Peixe-Zebra/imunologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Proteínas de Peixes/química , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Perfilação da Expressão Gênica/veterinária , Regulação da Expressão Gênica/imunologia , Filogenia , Alinhamento de Sequência/veterinária , Infecções Estreptocócicas/imunologia , Infecções Estreptocócicas/veterinária , Streptococcus agalactiae/fisiologia
11.
Vet Microbiol ; 236: 108369, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31500733

RESUMO

Suppurative meningitis-meningoencephalitis (M-ME) is a sporadic disease in neonatal ungulates and only a few studies have reported the involvement of Streptococcus bovis/Streptococcus equinus complex (SBSEC) members in bovine neonatal M-ME. The SBSEC taxonomy was recent revised and previous biotype II/2 was reclassified as S. gallolyticus subsp. pasteurianus (SGP). The aim of this study was to describe a case of fatal neonatal neurological syndrome associated with SGP in calves. Ten calves were monitored because of neurological hyperacute symptoms associate with bilateral hypopyon and death. They were not fed with maternal colostrum; two of them died and were subjected to bacteriological, histopathological and biomolecular analysis as well as antibiotic susceptibility test. Both animals presented lesions mostly concentrated to meninges and brain and had bilateral hypopyon. Nine strains isolated in purity from brain, ocular humors and colon were identified as S. bovis group by using the API Strep system and as S. gallolyticus by using the 16S rRNA sequence. Two of these strains where subjected to WGS analysis that confirmed the sub-species identification and the clonality of the two SGP strains. The strains were found resistant to OT, SXT, MTZ and EN and susceptible to AMP, AMC, KZ and CN. We hypothesized that the syndrome observed could be due to the lack of maternal colostrum feeding. A timely and precise diagnosis could have likely prevented the death of the calves and, since the zoonotic potential of SBSECs members is known, accurate and rapid identification is required.


Assuntos
Doenças dos Bovinos/microbiologia , Doenças do Sistema Nervoso Central/veterinária , Meningites Bacterianas/veterinária , Meningoencefalite/veterinária , Infecções Estreptocócicas/veterinária , Streptococcus gallolyticus , Animais , Bovinos , Doenças dos Bovinos/mortalidade , Doenças dos Bovinos/patologia , Doenças do Sistema Nervoso Central/microbiologia , Meningites Bacterianas/microbiologia , Meningites Bacterianas/mortalidade , Meningites Bacterianas/patologia , Meningoencefalite/microbiologia , Meningoencefalite/mortalidade , Meningoencefalite/patologia , Infecções Estreptocócicas/microbiologia , Infecções Estreptocócicas/patologia
12.
Fish Shellfish Immunol ; 93: 924-933, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31374315

RESUMO

Our previous studies demonstrated that the deletion of D2 fragment in tilapia Streptococcus agalactiae(GBS) attenuated strain YM001 is the main reason for the loss of virulence to tilapia. In this study, a Δ2 mutant that deletion of D2 fragment in parental virulent strain HN016 was constructed, and the safety, stability, immunogenicity, and growth characteristics, as well as the virulence mechanism of Δ2 mutant were evaluated. The results showed that Δ2 mutant was not pathogenic to tilapia, and the virulent revertants were not observed after 50 generations of passage. The RPS reached 96.11% at 15 days and 93.05% at 30 days, respectively, after intraperitoneal injection, while RPS reached 74.80% at 15 days and 53.16% at 30 days, respectively, after oral immunization. The growth of Δ2 mutant was significantly faster than YM001, and genes that were enriched in the nitrogen metabolism and arginine biosynthesis signaling pathway (arc, glnA, and gdhA) were identified as important candidate genes responsible for growth rate of S. agalactiae. The absence of D2 fragment affected the expression of Sip, therefore influencing the bacterial virulence. Altogether, this study demonstrated that deletion of D2 fragment in HN016 causes the loss of virulence to tilapia, and Δ2 mutant is a promising, better attenuated oral vaccine strain of S. agalactiae compared to YM001.


Assuntos
Vacinas Bacterianas/imunologia , Sequência de Bases , Ciclídeos/imunologia , Doenças dos Peixes/prevenção & controle , Deleção de Sequência , Infecções Estreptocócicas/veterinária , Streptococcus agalactiae/imunologia , Animais , Doenças dos Peixes/imunologia , Técnicas de Inativação de Genes/veterinária , Sorogrupo , Infecções Estreptocócicas/imunologia , Infecções Estreptocócicas/prevenção & controle , Streptococcus agalactiae/patogenicidade , Vacinas Atenuadas/imunologia , Virulência
13.
Enzyme Microb Technol ; 130: 109360, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31421723

RESUMO

Streptococcus uberis is a major mastitis-causing environmental pathogen, which rapid immunodetection has not been possible due to the absence of specific anti-Str. uberis antibodies. Recently, a specific antibody against the Str. uberis adhesion molecule (SUAM) has been designed. In the present study, the specificity and affinity of this antibody towards SUAM antigenic region SAPVYLGVSTE and Str. uberis cells are characterized, using experimental and in silico bioinformatic methods. The selectivity studies and bioinformatic analyses revealed high specificity of the antibody towards Str. uberis. The Kd value of SAPVYLGVSTE/anti-Str. uberis antibody complex was 27 ±â€¯6 nM, indicating the applicability of this antibody for the detection of Str. uberis. The anti-Str. uberis antibody was used as a specific biorecognition element of a biosensor for the detection of Str. uberis bacteria in phosphate buffer and in milk and these analyses took less than 20 min. The Str. uberis biosensor was also tested in the milk of cows suffering from mastitis and the obtained results were in good agreement with the conventional identification of this pathogen by microbiological plating.


Assuntos
Mastite Bovina/diagnóstico , Leite/microbiologia , Alimentos Crus/microbiologia , Infecções Estreptocócicas/veterinária , Streptococcus/isolamento & purificação , Animais , Anticorpos Antibacterianos/sangue , Afinidade de Anticorpos , Aderência Bacteriana , Técnicas Biossensoriais , Bovinos , Biologia Computacional , Feminino , Mastite Bovina/imunologia , Infecções Estreptocócicas/diagnóstico , Infecções Estreptocócicas/imunologia , Streptococcus/patogenicidade
14.
J Dairy Sci ; 102(10): 9360-9369, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31421887

RESUMO

Bovine clinical mastitis quarter foremilk samples were collected from 15 German dairy farms for the isolation of Streptococcus uberis strains. Samples were also collected from the 8 spots where Streptococcus uberis was most expected in the dairy environment to investigate the transmission behavior of Streptococcus uberis within the farm. The selected environmental spots for sampling were the inner surface of the milking liner, drinking troughs (on pasture and in the barn), exit area of milking parlor, bedding material from the lying area in the barn, passageway to pasture, lying area of soil or vegetation on pasture, and the barn area in front of the milking parlor. We performed pulsed-field gel electrophoresis on 237 Streptococcus uberis isolates to identify environmental strains that matched those from mastitis milk. The same strains were detected on the passageway to the pasture, milking parlor waiting area, in one of the liners, and a drinking trough. Streptococcus uberis strains showed high variability within farms and because identical strains (in mastitis milk and environment) were found in different environmental localizations, its transmission appears to be farm specific. Thus, to establish a farm-specific mastitis control strategy, the main environmental sources of Streptococcus uberis must be analyzed for matching strains. A molecular method such as pulsed-field gel electrophoresis is an important tool that can be used to obtain the necessary information.


Assuntos
Mastite Bovina/microbiologia , Infecções Estreptocócicas/veterinária , Streptococcus/isolamento & purificação , Animais , Bovinos , Indústria de Laticínios , Eletroforese em Gel de Campo Pulsado , Feminino , Abrigo para Animais , Leite/microbiologia , Infecções Estreptocócicas/microbiologia , Streptococcus/classificação
15.
J Fish Dis ; 42(11): 1553-1562, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31448825

RESUMO

The potential of selection to improve resistance to streptococcosis was evaluated in a commercial population of Nile tilapia in Thailand. The base generation (G0) consisted of offspring from 98 sires and 149 dams using a partly nested design. At 60 days post-hatch, 30 fish from each family were injected intraperitoneally with a Streptococcosis agalactiae solution (1 × 109  CFU/ml) and evaluated for 14 days. Disease resistance was recorded as the number of days from challenge until death (DD) and as a binary (BIN) trait (dead/alive) on day 14. Three models were used for genetic analyses: Cox frailty model for DD; animal model for DD; and animal model for BIN. Age at challenge was fitted as a covariate and contemporary group as fixed or random effect, depending on the model. Fish from the 18 most resistant families were selected to produce the first generation (G1). Heritability estimates for G0 were 0.22, 0.14 ± 0.02 and 0.11 ± 0.02 for the Cox, linear DD and linear BIN models, respectively. Selection response indicated that the risk of death decreased to 54%, survival time increased to 3.4 days and survival rate increased to 21%. These results suggest that genetic improvement is possible for this population.


Assuntos
Ciclídeos , Resistência à Doença , Doenças dos Peixes/genética , Seleção Genética , Infecções Estreptocócicas/veterinária , Streptococcus agalactiae/fisiologia , Animais , Doenças dos Peixes/microbiologia , Modelos Biológicos , Infecções Estreptocócicas/genética , Infecções Estreptocócicas/microbiologia
16.
J Dairy Res ; 86(3): 307-314, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31451129

RESUMO

This study aimed to evaluate the transcriptional changes occurring in isolated perfused mammary alveolar tissue in response to inoculation with S. agalactiae and to identify the most affected biological functions and pathways after 3 h. Four udders taken at slaughter from cows with healthy mammary gland were perfused ex situ with warmed and gassed Tyrode's solution. Mammary alveolar tissue samples were taken from the left fore and rear quarters (IQ-inoculated quarters) before inoculation (hour 0) and at 3 h post inoculation (hpi) and at the same times from control right fore and rear quarters (not inoculated: NIQ). A total of 1756 differentially expressed genes (DEGs) were identified between IQ and NIQ at 3 hpi using edgeR package. Within this set of DEGs, 952 were up regulated and mainly involved with innate immune response and inflammatory response, e.g., CD14, CCL5, TLR2, IL-8, SAA3, as well as in transcriptional regulation such as FOS, STAT3 and NFKBIA. Genes down-regulated (804) included those involved with lipid synthesis e.g., APOC2, SCD, FABP3 and FABP4. The most affected pathways were chemokine signaling, Wnt signaling and complement and coagulation cascades, which likely reflects the early stage response of mammary tissue to S. agalactiae infection. No significant gene expression changes were detected by RNA-Seq in the others contrasts. Real time-PCR confirmed the increase in mRNA abundance of immune-related genes: TLR2, TLR4, IL-1ß, and IL-10 at 3 hpi between IQ and NIQ. The expression profiles of Casp1 and Bax for any contrasts were unaffected whereas Bcl2 was increased in IQ, which suggests no induction of apoptosis during the first hours after infection. Results provided novel information regarding the early functional pathways and gene network that orchestrate innate immune responses to S. agalactiae infection. This knowledge could contribute to new strategies to enhance resistance to this disease, such as genomic selection.


Assuntos
Perfilação da Expressão Gênica/veterinária , Glândulas Mamárias Animais/metabolismo , Infecções Estreptocócicas/veterinária , Streptococcus agalactiae , Animais , Bovinos , Feminino , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica , Imunidade/genética , Inflamação/genética , Mastite Bovina/genética , Mastite Bovina/imunologia , Mastite Bovina/microbiologia , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Infecções Estreptocócicas/genética , Infecções Estreptocócicas/imunologia
17.
Fish Shellfish Immunol ; 94: 249-257, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31470139

RESUMO

In recent years, streptococcal diseases have severely threatened the development of tilapia aquaculture, but effective prevention and control methods have not yet been established. To understand the immune responses of vaccinated Nile tilapia (Oreochromis niloticus), digital gene expression (DGE) technology was applied in this study to detect the gene expression profile of the Nile tilapia (O. niloticus) liver in response to ScpB (Streptococcal C5a peptidase from group B Streptococcus, ScpB) vaccination and a Streptococcus agalactiae-challenge. The control and the ScpB-vaccinated Nile tilapia yielded a total of 25,788,734 and 27,088,598 clean reads, respectively. A total of 1234 significant differentially expressed unigenes were detected (P < 0.05), of which 236 were significantly up-regulated, and 269 were significantly down-regulated (P < 0.05, |fold|>2, FDR<0.05). Of the differentially expressed gene, the identified genes which were enriched using databases of GO and KEGG could be categorized into a total of 67 functional groups and were mapped to 153 signaling pathways including 15 immune-related pathways. The differentially expressed genes (TLR1, TLR2, TLR3, TLR5, TLR9, MyD88, C3, IL-1ß, IL-10) were detected in the expression profiles, and this was subsequently verified via quantitative real-time PCR (qPCR). The results of this study can serve as a basis for future research not only on the molecular mechanism of S. agalactiae invasion, but also on the anti-S. agalactiae mechanism in targeted tissues of Nile tilapia.


Assuntos
Ciclídeos/imunologia , Doenças dos Peixes/genética , Perfilação da Expressão Gênica/veterinária , Regulação da Expressão Gênica , Infecções Estreptocócicas/veterinária , Streptococcus agalactiae/fisiologia , Animais , Ciclídeos/genética , Regulação para Baixo , Doenças dos Peixes/imunologia , Doenças dos Peixes/microbiologia , Biblioteca Gênica , Ontologia Genética , Fígado/metabolismo , Fígado/microbiologia , Infecções Estreptocócicas/genética , Infecções Estreptocócicas/imunologia , Infecções Estreptocócicas/microbiologia , Vacinas Estreptocócicas/administração & dosagem , Regulação para Cima
18.
Fish Shellfish Immunol ; 93: 863-870, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31422178

RESUMO

Interleukins (ILs) are a subgroup of cytokines, which are molecules involved in the intercellular regulation of the immune system. These cytokines have been extensively studied in mammalian models, but systematic analyses of fish are limited. In the current study, 3 IL genes from golden pompano (Trachinotus ovatus) were characterized. The IL-1ß protein contains IL-1 family signature motif, and four long helices (αA - αD) in IL-11 and IL-34, which were well conserved. All 3 ILs clustered phylogenetically with their respective IL relatives in mammalian and other teleost species. Under normal physiological conditions, the expression of IL-1ß, IL-11, and IL-34 were detected at varied levels in the 11 tissues examined. Most of the 3 ILs examined were highly expressed in liver, spleen, kidney, gill, or skin. Following pathogenic bacterial, viral, or parasitic challenge, IL-1ß, IL-11, and IL-34 exhibited distinctly different expression profiles in a time-, tissue-, and pathogen-dependent manner. In general, IL-1ß was expressed at higher levels following challenge with all pathogens examined than was observed for IL-11 and IL-34. Furthermore, Streptococcus agalactiae and Cryptocaryon irritans caused higher levels of IL-1ß and IL-11 expression than Vibrio harveyi and viral nervous necrosis virus (VNNV). The increased expression of IL-34 caused by VNNV and C. irritans were higher than that caused by V. harveyi and S. agalactiae. These results suggest that these 3 ILs in T. ovatus may play different effect pathogen type specific responses.


Assuntos
Doenças dos Peixes/imunologia , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Peixes/imunologia , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Animais , Cilióforos/fisiologia , Infecções por Cilióforos/imunologia , Infecções por Cilióforos/veterinária , Perfilação da Expressão Gênica/veterinária , Interleucina-11/genética , Interleucina-11/imunologia , Interleucina-1beta/genética , Interleucina-1beta/imunologia , Interleucinas/genética , Interleucinas/imunologia , Infecções Estreptocócicas/imunologia , Infecções Estreptocócicas/veterinária , Streptococcus agalactiae/fisiologia , Vibrio/fisiologia , Vibrioses/imunologia , Vibrioses/veterinária
19.
Microbiol Res ; 228: 126304, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31422235

RESUMO

Streptococcus suis (S. suis) is an important zoonotic pathogen that causes major economic losses in the pig industry worldwide. The S. suis cell division process is an integral part of its growth and reproduction, which is controlled by a complex regulatory network. Pyruvate dehydrogenase (PDH), which catalyzes the oxidative decarboxylation of pyruvate to form acetyl-CoA, while reducing NAD + to NADH, plays an important role in energy metabolism. Recently, we reported that pdh regulates virulence by reducing stress tolerance and biofilm formation in S. suis serotype 2. In this study, we found that deletion of the pdh gene in S. suis resulted in abnormal cell chains, plump morphology and abnormal localization of the Z rings, indicating that the knockout mutant is impaired in its ability to divide. In addition, the interaction between FtsZ and PDH in vitro was confirmed by ELISA, and qRT-PCR analysis revealed that the deletion of the pdh gene results in differential expression of the division-related genes ftsZ, ftsK, ftsl, zapA, divIC, pbp1a, rodA, mreD, and sepF. These results indicate that pdh is involved in the normal formation of Z rings and cell morphology during S. suis cell division.


Assuntos
Divisão Celular/genética , Divisão Celular/fisiologia , Complexo Piruvato Desidrogenase/genética , Streptococcus suis/citologia , Streptococcus suis/genética , Streptococcus suis/fisiologia , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/fisiologia , Proteínas do Citoesqueleto/genética , Deleção de Genes , Perfilação da Expressão Gênica , Regulação Bacteriana da Expressão Gênica , Técnicas de Inativação de Genes , Infecções Estreptocócicas/microbiologia , Infecções Estreptocócicas/veterinária , Streptococcus suis/patogenicidade , Suínos , Virulência , Fatores de Virulência/genética
20.
Fish Shellfish Immunol ; 92: 842-850, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31284046

RESUMO

Streptococcus dysgalactiae is a gram-positive bacterium and a harmful aquaculture pathogen. To investigate the immune response against S. dysgalactiae, we performed transcriptome analysis of the head kidney and spleen of cobia (Rachycentron canadum) using RNA-seq. Total RNA was extracted from the head kidney and spleen of cobia, 1 and 2 days after treatment with S. dysgalactiae or control PBS. After RNA purification and cDNA library generation, sequencing was performed using the Illumina HiSeq™ 4000 platform. The filtering and de novo assembling transcripts were annotated using several databases. To identify differentially expressed genes (DEGs) between the S. dysgalactiae and PBS groups, the mapped values of fragments per kilobase of transcripts per million fragments were calculated. After de novo assembly, a total of 106,984 transcripts were detected, with an N50 of 3020 bp. These transcripts were annotated and categorised into a total of 7608 genes based on the KEGG pathway database. DEGs (2-fold difference) were calculated by comparing the S. dysgalactiae and PBS control group gene expression levels at each time point. The DEGs were mainly annotated into signal transduction and immune system categories, based on the KEGG database. The DEGs were significantly enriched in the immune-related pathways - "cytokine-cytokine receptor interaction", "complement and coagulation cascades", and "hematopoietic cell linage". In this study, immune-related genes responding to S. dysgalactiae were detected, and several immune system pathways were categorized. We identified the IL17C-related pathway for inducing the expression of pro-inflammatory cytokine genes (IL-1ß, IL-6, and IFNγ). Additionally, neutrophil-related genes (CSF3, CD121, and CD114) were induced in the spleen after S. dysgalactiae infection. It was suggested that these pathways contribute to immune responses against S. dysgalactiae infection. The data revealed in this study may offer improved strategies against S. dysgalactiae infection in cobia.


Assuntos
Doenças dos Peixes/imunologia , Peixes/genética , Peixes/imunologia , Transcriptoma , Animais , Perfilação da Expressão Gênica/veterinária , Rim Cefálico/imunologia , Sequenciamento de Nucleotídeos em Larga Escala/veterinária , Baço/imunologia , Infecções Estreptocócicas/imunologia , Infecções Estreptocócicas/veterinária , Streptococcus/fisiologia
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