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1.
Sci Rep ; 11(1): 17227, 2021 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-34446770

RESUMO

Cattle vary in their susceptibility to infection and immunopathology, but our ability to measure and longitudinally profile immune response variation is limited by the lack of standardized immune phenotyping assays for high-throughput analysis. Here we report longitudinal innate immune response profiles in cattle using a low-blood volume, whole blood stimulation system-the ImmunoChek (IChek) assay. By minimizing cell manipulation, our standardized system minimizes the potential for artefactual results and enables repeatable temporal comparative analysis in cattle. IChek successfully captured biological variation in innate cytokine (IL-1ß and IL-6) and chemokine (IL-8) responses to 24-hr stimulation with either Gram-negative (LPS), Gram-positive (PamCSK4) bacterial or viral (R848) pathogen-associated molecular patterns (PAMPs) across a 4-month time window. Significant and repeatable patterns of inter-individual variation in cytokine and chemokine responses, as well as consistent high innate immune responder individuals were identified at both baseline and induced levels. Correlation coefficients between immune response read-outs (IL-1ß, IL-6 and IL-8) varied according to PAMP. Strong significant positive correlations were observed between circulating monocytes and IL-6 levels for null and induced responses (0.49-0.61) and between neutrophils and cytokine responses to R848 (0.38-0.47). The standardized assay facilitates high-throughput bovine innate immune response profiling to identify phenotypes associated with disease susceptibility and responses to vaccination.


Assuntos
Bovinos/imunologia , Imunidade Inata/imunologia , Testes Imunológicos/métodos , Padrões Moleculares Associados a Patógenos/imunologia , Imunidade Adaptativa/imunologia , Animais , Bovinos/sangue , Ensaio de Imunoadsorção Enzimática , Imidazóis/imunologia , Interleucina-1beta/sangue , Interleucina-1beta/imunologia , Interleucina-6/sangue , Interleucina-6/imunologia , Interleucina-8/sangue , Interleucina-8/imunologia , Lipopolissacarídeos/imunologia , Neutrófilos/imunologia , Padrões Moleculares Associados a Patógenos/sangue , Fatores de Tempo
2.
Front Immunol ; 12: 674484, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34305904

RESUMO

East Coast Fever (ECF), caused by the tick-borne apicomplexan parasite Theileria parva, remains one of the most important livestock diseases in sub-Saharan Africa with more than 1 million cattle dying from infection every year. Disease prevention relies on the so-called "Infection and Treatment Method" (ITM), which is costly, complex, laborious, difficult to standardise on a commercial scale and results in a parasite strain-specific, MHC class I-restricted cytotoxic T cell response. We therefore attempted to develop a safe, affordable, stable, orally applicable and potent subunit vaccine for ECF using five different T. parva schizont antigens (Tp1, Tp2, Tp9, Tp10 and N36) and Saccharomyces cerevisiae as an expression platform. Full-length Tp2 and Tp9 as well as fragments of Tp1 were successfully expressed on the surface of S. cerevisiae. In vitro analyses highlighted that recombinant yeast expressing Tp2 can elicit IFNγ responses using PBMCs from ITM-immunized calves, while Tp2 and Tp9 induced IFNγ responses from enriched bovine CD8+ T cells. A subsequent in vivo study showed that oral administration of heat-inactivated, freeze-dried yeast stably expressing Tp2 increased total murine serum IgG over time, but more importantly, induced Tp2-specific serum IgG antibodies in individual mice compared to the control group. While these results will require subsequent experiments to verify induction of protection in neonatal calves, our data indicates that oral application of yeast expressing Theileria antigens could provide an affordable and easy vaccination platform for sub-Saharan Africa. Evaluation of antigen-specific cellular immune responses, especially cytotoxic CD8+ T cell immunity in cattle will further contribute to the development of a yeast-based vaccine for ECF.


Assuntos
Imunização/métodos , Vacinas Protozoárias/imunologia , Theileria parva/imunologia , Theileriose/prevenção & controle , Animais , Linfócitos T CD8-Positivos/imunologia , Bovinos/imunologia , Imunização/veterinária , Interferon gama/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Vacinas Protozoárias/uso terapêutico , Linfócitos T Citotóxicos/imunologia , Carrapatos , Leveduras/imunologia
3.
Res Vet Sci ; 139: 121-126, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34298285

RESUMO

The objective of this study was to estimate the prevalence of failure of passive transfer of immunity (FPTI) in dairy calves in the south-west region of Western Australia herds. A cross-sectional study was conducted in 26/140 dairy farms and serum samples were collected from 495 healthy 2-7 day-old calves. A radial immunodiffusion (RID) test was used to determine the concentration of serum IgG and calves were classified as having FPTI if the IgG concentration was less than 10 mg/mL. Estimation of FPTI was also assessed using two indirect methods using serum total protein (STP) and a brix refractometer. The estimated prevalence of FPTI was found to be 8.7% (43 calves out of 495) by RID with the concentration of IgG ranging between 0 and 6.2 mg/ml. The STP was found to vary from 46 to 96 mg/mL and using a cut-off point of 55 mg/mL the calf level prevalence was estimated as 7.1% (33 calves). Using the brix refractometer, the prevalence was found to be 13.1% (65 calves) with the refractometer reading ranging 6-14% of IgG. In the present study there was no association between calf-level factors (age, sex and breed) and FPTI. There was a higher correlation of the RID test results and the STP results compared to the RID and brix refractometer results. It is concluded that the prevalence of FPTI in dairy calves in the south-west region of Western Australia is low (8.7%) and the brix refractometer is not a reliable indirect method for determining passive transfer of immunity to calves.


Assuntos
Bovinos , Colostro , Imunização Passiva , Imunoglobulina G , Animais , Animais Recém-Nascidos , Bovinos/imunologia , Estudos Transversais , Feminino , Imunização Passiva/veterinária , Gravidez , Prevalência , Austrália Ocidental/epidemiologia
4.
Front Immunol ; 12: 643206, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34267745

RESUMO

The growing world population (7.8 billion) exerts an increased pressure on the cattle industry amongst others. Intensification and expansion of milk and beef production inevitably leads to increased risk of infectious disease spread and exacerbation. This indicates that improved understanding of cattle immune function is needed to provide optimal tools to combat the existing and future pathogens and improve food security. While dairy and beef cattle production is easily the world's most important agricultural industry, there are few current comprehensive reviews of bovine immunobiology. High-yielding dairy cattle and their calves are more vulnerable to various diseases leading to shorter life expectancy and reduced environmental fitness. In this manuscript, we seek to fill this paucity of knowledge and provide an up-to-date overview of immune function in cattle emphasizing the unresolved challenges and most urgent needs in rearing dairy calves. We will also discuss how the combination of available preventative and treatment strategies and herd management practices can maintain optimal health in dairy cows during the transition (periparturient) period and in neonatal calves.


Assuntos
Doenças dos Bovinos/imunologia , Bovinos/imunologia , Animais , Feminino , Masculino
5.
Reprod Domest Anim ; 56(9): 1192-1199, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34216048

RESUMO

The goal of this study was to characterize and evaluate the main markers of macrophages, T lymphocytes, B lymphocytes and plasmocytes in the testis of juvenile and adult yaks by quantitative real-time polymerase chain reaction and immunohistochemistry. Within the same age group, the mRNA expression of CD68 was always highest, followed by that of CD3ε, CD79α, IgG and IgA. Moreover, CD68, CD3, CD79α, IgA and IgG positive cells were all located in the testicular interstitial tissues of juvenile and adult yaks. In the same age group, the frequency of CD68 positive macrophages was higher than that of CD3 positive T lymphocytes, which was followed by that of CD79α positive B lymphocytes and IgA and IgG positive plasmocytes. No significant difference was observed between the B lymphocyte and plasmocyte frequencies in yak testes. Furthermore, CD68, CD3ε, CD79α, IgA and IgG mRNA expression levels and the frequencies of CD68, CD3, CD79α, IgA and IgG positive cells increased from juveniles to adults. Similarly, the frequencies of CD68, CD3, CD79α, IgA and IgG positive cells also increased with age. These results suggest that in the yak testis, the immune defence system against pathogens might primarily comprise macrophages and T lymphocytes in the testicular interstitial tissue. Moreover, the testicular immune environment may mature and expand to a fully functional state in adult yaks. The low frequencies of B lymphocyte and plasmocyte in yaks, differing from those in rodents and humans, might be related to the fact that yaks live in low-oxygen plateaus.


Assuntos
Bovinos/imunologia , Fatores Imunológicos/metabolismo , Testículo/imunologia , Envelhecimento , Animais , Leucócitos/imunologia , Masculino , RNA Mensageiro/metabolismo , Testículo/citologia
6.
BMC Vet Res ; 17(1): 233, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34210328

RESUMO

BACKGROUND: The warming climate is causing livestock to experience heat stress at an increasing frequency. Holstein cows are particularly susceptible to heat stress because of their high metabolic rate. Heat stress negatively affects immune function, particularly with respect to the cell-mediated immune response, which leads to increased susceptibility to disease. Cattle identified as having enhanced immune response have lower incidence of disease. Therefore, the objective of this study was to evaluate the impact of in vitro heat challenge on blood mononuclear cells from dairy cattle, that had previously been ranked for immune response, in terms of heat shock protein 70 concentration, nitric oxide production, and cell proliferation. RESULTS: Blood mononuclear cells from dairy cattle classified as high immune responders, based on their estimated breeding values for antibody and cell-mediated responses, produced a significantly greater concentration of heat shock protein 70 under most heat stress treatments compared to average and low responders, and greater cell-proliferation across all treatments. Similarly, a trend was observed where high responders displayed greater nitric oxide production compared to average and low responders across heat treatments. CONCLUSION: Overall, these results suggest that blood mononuclear cells from high immune responder dairy cows are more thermotolerant compared to average and low immune responders.


Assuntos
Bovinos/fisiologia , Resposta ao Choque Térmico/fisiologia , Imunidade , Leucócitos Mononucleares/metabolismo , Animais , Bovinos/imunologia , Indústria de Laticínios , Feminino , Proteínas de Choque Térmico HSP70/metabolismo , Óxido Nítrico/metabolismo
7.
Vet Immunol Immunopathol ; 238: 110288, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34182229

RESUMO

Interleukin 8 (IL8) is a major mediator of the innate immune response. Polymorphisms in this gene are associated with susceptibility to inflammatory disease in humans. Two major promoter polymorphic haplotypes (IL8-h1 and IL8-h2) segregating in cattle populations have shown a significant effect on the immune response profile in calves but their implications for transition cow immunity have not been established. The aims of this study were to assess functional relevance of the IL8 haplotypes on the immunological traits of periparturient cows (n = 32) belonging to three genetic groups: Holstein (HO), Simmental (SI) and their crosses (CR) and to evaluate the frequency of IL8 haplotypes in the HO (dairy) and SI (dual purpose) pure breeds. IL8 haplotypes showed a significant effect on circulating number of both T helper lymphocytes (P = 0.0133) and T cytotoxic lymphocytes (P = 0.0024). Differences in percentage of CD14+ monocytes and T lymphocyte subsets were found between haplotype groups at different time points. Plasma concentrations of Serum Amyloid A (SAA) and Haptoglobin (Hp) were enhanced at calving in IL8-h2 (P = 0.0019, P = 0.0029) and IL8-het (P = 0.050 and P = 0.052) respectively, compared with IL8-h1 cows. In contrast, significantly lower levels of reactive oxygen metabolites (d-ROMs) activation were identified in IL8-h2 and IL8-het cows after calving compared with IL8-h1 cows. Furthermore, genotyping results showed that SI cows have a high frequency of the homozygous IL8-h2 haplotype compared to the HO cows (87.5 % vs 40 %) which reflects the different selective pressure between the two pure breeds. In conclusion, our preliminary data suggests that IL8 promoter haplotype is associated with significant and dynamic changes in immunological traits during peripartum and early lactation period. Future work will focus on a more comprehensive assessment of immune changes in additional cows.


Assuntos
Bovinos/genética , Bovinos/imunologia , Interleucina-8/genética , Período Periparto/sangue , Animais , Antígenos CD/genética , Antígenos CD/metabolismo , Feminino , Regulação da Expressão Gênica , Homozigoto , Período Periparto/imunologia
8.
Sci Rep ; 11(1): 12771, 2021 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-34140546

RESUMO

Objective of experiment was to determine whether oxidative stress (OS) and inflammation altered embryonic loss in dairy cows. Blood samples were collected at days 0, 16, 32 and 60 after timed (AI) from 200 Holstein cows to determine embryonic loss based on interferon-stimulated gene-15 (ISG15) mRNA expression (day 16) and ultrasound at day 32 and day 60. Leucocyte expressions of mRNA TLR2, TLR4, TNF-α, IL1B, IL10, STAT3 (inflammation), PTGS2, PTGES (prostaglandin synthesis), and PLA2G4A and ALOX5AP (eicosanoid metabolism) at days 0 and 16 were determined. Plasma redox status for antioxidant enzymatic activities of glutathione peroxidase (GPX), superoxide dismutase (SOD), total antioxidant capacity (TAC), and concentrations of malondialdehyde (MDA) were determined at days 0, 16, 32 and 60. All antioxidant-redox responses were beneficially significant in pregnant cows diagnosed pregnant at day16 and sustained pregnancy to day 60 compared to non-pregnant cows at day16 or pregnant at day16 and lost embryos by days 32 or 60. The leucocyte mRNA expressions of TLR2, TLR4, STAT 3, IL1B, PTGS2, PLA2G4A and ALOX5AP were greater and PTGES was lower at day16 in pregnant cows that lost embryos early (P < 0.05). In conclusion peripheral leucocyte molecular indicators of inflammation and plasma indicators of OS were altered in pregnant cows undergoing embryonic losses compared to cows with a sustained pregnancy.


Assuntos
Bovinos/imunologia , Perda do Embrião/imunologia , Perda do Embrião/veterinária , Inflamação/imunologia , Inflamação/veterinária , Leucócitos/metabolismo , Estresse Oxidativo , Animais , Antioxidantes/metabolismo , Bovinos/sangue , Eicosanoides/metabolismo , Perda do Embrião/sangue , Feminino , Regulação da Expressão Gênica , Glutationa Peroxidase/metabolismo , Inflamação/sangue , Interferons/metabolismo , Oxirredução , Gravidez , Prostaglandinas/biossíntese , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Superóxido Dismutase/metabolismo , Ultrassonografia
9.
Res Vet Sci ; 138: 148-160, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34144282

RESUMO

The objective of this randomized, placebo-controlled, double-blinded field trial was to investigate the effects of oral administration of purple coneflower (Echinacea purpurea L. (EP)) on performance, health and immune parameters in calves. Calves (n = 27) were enrolled to three groups (9 calves per group): 0.5 g EP/calf per day (ECL), 5 g EP/calf per day (ECH) or placebo. Calves were vaccinated with Bluetongue-Virus (BTV) serotype 4 vaccine to investigate EPs effects on seroconversion. Clinical and performance parameters, inter alia body weight, health and milk intake were recorded for 57 days. Blood samples were analyzed for BTV antibodies and IgG by ELISA, white and red blood cell counts by flow cytometry and mRNA abundance of various inflammatory markers in leukocytes (IL-1ß, IL-8, tumor necrosis factor α (TNFα), cyclooxygenase 2 (Cox-2) and prostaglandin E synthase) was studied. The findings demonstrated no differences between groups regarding performance parameters. In all groups, calves suffered from diarrhea for a minimum of 2 days, but EP reduced the number of diarrhea days by 44% in ECL and increased the body temperature. Interestingly, ECL resulted in an increased number of respiratory disease days during the follow-up period. EP did not change blood cell and IgG counts, whereas eosinophil granulocytes were reduced in ECL. Decreased levels of hemoglobin and hematocrit were found in ECH. Prostaglandin E synthase levels in leukocytes were higher in ECL and ECH, whereas no differences were obtained for IL-1ß, IL-8, TNFα and Cox-2. Due to the unexpected occurrence of BTV seropositive calves before the first vaccination, 13 calves were excluded from the evaluation on seroconversion and no statistical analyses could be performed regarding antibody production. BTV-4 antibodies were not produced in 4 placebo-calves, whereas 4 of 5 and 1 of 6 ECL- and ECH-calves produced antibodies. Further investigations are needed to draw final conclusions on mode of action and efficacy of EP in calves.


Assuntos
Vírus Bluetongue/imunologia , Bovinos/fisiologia , Echinacea/química , Extratos Vegetais/administração & dosagem , Vacinação/veterinária , Vacinas Virais/imunologia , Animais , Bovinos/crescimento & desenvolvimento , Bovinos/imunologia , Método Duplo-Cego , Feminino , Masculino , Extratos Vegetais/química , Soroconversão
10.
Res Vet Sci ; 138: 53-61, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34111714

RESUMO

The interruption of the maternal-filial bond in young calves can alter the physiological responses due to increased stress at this moment. Therefore, we aimed to analyze the association between age at weaning and the immune responses of 64 beef calves weaned abruptly. The animals were distributed in three weaning (W) treatments: hyper-early (W30), early (W75) and conventional (W180). The treatments agree with the weaning ages used in cow-calf systems in South America. Blood samples were collected of all experimental animals on the day of weaning and days 1, 2 and 7 post-weaning day of the three treatments. Blood samples were used to analyze hematological variables, total plasma proteins (TPP), fibrinogen, serum amyloid A protein (SAA) and cortisol. The variables analyzed were influenced by the sampling day (P < 0.001) and the calf gender (P < 0.05), and an interaction between treatment x sampling day was observed. Over the study period, high serum cortisol levels were observed for W30 calves. The serum amyloid A protein was significantly influenced by sampling day. When compared to W180 calves, W30 and W75 animals showed prolonged concentrations in plasma fibrinogen. In addition, they presented neutrophilia and lymphopenia during the 180-187 days period, which resulted in a greater neutrophil:lymphocyte ratio (N:L ratio). Calf gender resulted in changes in the number of blood leukocytes (P < 0.05). This result provides an alert for weaning at an early age, indicating that different management strategies must be tested to minimize physiological instabilities in critical periods of the life of animals.


Assuntos
Bovinos/fisiologia , Imunidade/fisiologia , Desmame , Animais , Brasil , Bovinos/imunologia , Feminino , Masculino
11.
J Dairy Res ; 88(2): 189-193, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33952363

RESUMO

In this study it is hypothesized that there are differences between immunoglobulin G (IgG) content in colostrum from beef (Chianina, Podolica) and dairy (Holstein Friesian) cows and that variables such as breed, and parity can influence IgG content. The further objective was to determine if these factors may vary in terms of sensitivity, specificity and the cut point when data obtained with the digital Brix refractometer is compared with the gold standard radial immunodiffusion assay (RID). A total of 90 samples of first-milking colostrum were collected within 2 h after parturition. IgG concentration was determined indirectly by digital Brix refractometer and directly by RID. Results obtained by RID were compared among breed and parity. For the digital Brix refractometer, sensitivity and specificity to detect colostrum with an IgG concentration lower than 50 g/l were calculated and the optimal cut-point was selected for each breed. Samples containing less than <50 g/l IgG accounted for 15.9% of the total. Parity influenced colostral IgG concentration and beef cows had a higher mean concentration of IgG (101.1 g/l in Chianina and 90.6 g/l in Podolica) than dairy cows (71.1 g/l in Holstein Friesian) First parity Chianina cows had the highest IgG mean content (116.1 g/l). At the optimal cut-point for Brix refractometer (20%) sensitivity and specificity were 0.93 (0.84-0.97) and 0.81 (0.70-0.88), however, a breed-related cut-point could be used to reduce evaluation error. Linear regression modeling showed that refractometer data were related to RID (r = 0.78). Results obtained suggest that breed and parity can influence IgG content of colostrum and, despite the Brix refractometer being an excellent on-farm tool, a breed-based definition of optimal cut point is needed.


Assuntos
Bovinos/imunologia , Colostro/imunologia , Imunoglobulina G/análise , Refratometria/veterinária , Agricultura/métodos , Animais , Indústria de Laticínios/métodos , Feminino , Itália , Carne Vermelha , Refratometria/instrumentação , Sensibilidade e Especificidade
12.
J Dairy Res ; 88(2): 194-200, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33926602

RESUMO

Provision of good quality colostrum is essential for the passive immunity and nutrition of newborn calves. In order to better predict the quality of colostrum and the transfer of passive immunity, the relationships between colostrum components and between calf serum components were examined in this study. Samples of bulk tank milk, colostrum pooled from several cows 0-4 d postpartum, and colostrum collected from individual cows twice daily for 3 d post-partum were compared. With the exception of fat percentage, there were strong correlations between the levels of the components in the pooled colostrum and in the individual cow colostrum collected 0-1 d postpartum. The correlations between total solids as measured by Brix refractometry and total protein, immunoglobulin G (IgG), lactose % and protein % in colostrum within 1 d postpartum and pooled colostrum were 0.92, 0.90, -0.88 and 0.98, respectively. These high correlations enabled these colostrum components to be accurately predicted from Brix % and therefore, the volume of colostrum required to feed neonate calves can be optimised based on Brix refractometry to avoid failure of passive immunity transfer. To assess whether the components obtained from colostrum were correlated in calf blood, newborn calves were separated from their dams before suckling and blood sampled before feeding (day 0), and on days 1 and 7, after receiving colostrum or milk twice a day. The correlations between glucose, total protein, IgG, and gamma-glutamyl transferase (GGT) levels in the calf blood were lower than the correlations observed between the colostrum components. The highest correlation was between serum protein measured by refractometer and serum IgG within one week postpartum. GGT activity was not a good indicator of serum IgG levels. However, serum protein refractometer measurements predicted serum IgG level with high accuracy, providing an on-farm test to determine that calves have received sufficient passive immunity and colostrum components.


Assuntos
Proteínas Sanguíneas/análise , Bovinos/imunologia , Colostro/química , Imunoglobulina G/sangue , Proteínas do Leite/análise , Refratometria/veterinária , Animais , Animais Recém-Nascidos/sangue , Animais Recém-Nascidos/imunologia , Colostro/imunologia , Indústria de Laticínios , Feminino , Imunidade Materno-Adquirida/imunologia , Imunoglobulina G/análise , Lactose/análise , Gravidez , gama-Glutamiltransferase/sangue
13.
ISME J ; 15(8): 2306-2321, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33649551

RESUMO

The gut microbiota is a complex ecological community that plays multiple critical roles within a host. Known intrinsic and extrinsic factors affect gut microbiota structure, but the influence of host genetics is understudied. To investigate the role of host genetics upon the gut microbiota structure, we performed a longitudinal study in which we evaluated the hindgut microbiota and its association with animal growth and immunity across life. We evaluated three different growth stages in an Angus-Brahman multibreed population with a graduated spectrum of genetic variation, raised under variable environmental conditions and diets. We found the gut microbiota structure was changed significantly during growth when preweaning, and fattening calves experienced large variations in diet and environmental changes. However, regardless of the growth stage, we found gut microbiota is significantly influenced by breed composition throughout life. Host genetics explained the relative abundances of 52.2%, 40.0%, and 37.3% of core bacterial taxa at the genus level in preweaning, postweaning, and fattening calves, respectively. Sutterella, Oscillospira, and Roseburia were consistently associated with breed composition at these three growth stages. Especially, butyrate-producing bacteria, Roseburia and Oscillospira, were associated with nine single-nucleotide polymorphisms (SNPs) located in genes involved in the regulation of host immunity and metabolism in the hindgut. Furthermore, minor allele frequency analysis found breed-associated SNPs in the short-chain fatty acids (SCFAs) receptor genes that promote anti-inflammation and enhance intestinal epithelial barrier functions. Our findings provide evidence of dynamic and lifelong host genetic effects upon gut microbiota, regardless of growth stages. We propose that diet, environmental changes, and genetic components may explain observed variation in critical hindgut microbiota throughout life.


Assuntos
Bactérias/classificação , Bovinos/genética , Microbioma Gastrointestinal , Animais , Bovinos/crescimento & desenvolvimento , Bovinos/imunologia , Ácidos Graxos Voláteis , Estudos Longitudinais
14.
Prev Vet Med ; 189: 105306, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33721672

RESUMO

Inadequate transfer of passive immunity (TPI) is associated with increased risk for calfhood disease and increased risk of mortality and morbidity. Accurately diagnosing calves and herds with inadequate TPI is of primary importance and brix (BRIX) or classical refractometer (REF) devices are more practical for this purpose than measuring the serum immunoglobulin G concentration in neonatal calves. We previously reported a systematic review and meta-analysis for quantifying the pooled accuracy of BRIX and REF for detecting calves with serum IgG < 10 g/L noting that sparse data were available especially because studies did not report the same thresholds. We updated the previous systematic review using different methods that accounted for the test results distribution in calves with or without inadequate TPI. With this approach, all reported cut-offs for a specific study are used in that Bayesian approach that quantifies how accuracy varied among all reported thresholds. Five new manuscripts were included, which represented 4 new studies since the initial study was performed. A total of 11 REF and 9 BRIX studies were available. The meta-analytic methods allowed reporting variation of the true and false positive rate across and among all reported cut-offs. Pooled points estimates (95 % Bayesian credible intervals) for sensitivity (Se) and specificity (Sp) of REF < 5.5 g/L were 86.1 % (68.5-97.9%) and 76.2 % (65.9-88.4%) whereas BRIX < 8.4 % was associated with Se of 91.6 % (77.2-99.5%) and Sp of 88.2 % (65.4-99.8%). Interestingly, the accuracy (Se + Sp-1) was generally higher for BRIX than for REF at the reported cut-offs. Besides the benefit of providing pooled estimates for all reported and unreported BRIX and REF thresholds, the general framework used in this study could potentially be used in many veterinary diagnostic tests studies that reported multiple thresholds accounting for potentially different tests distributions in population with and without the target condition.


Assuntos
Bovinos/imunologia , Imunidade Materno-Adquirida , Refratometria , Animais , Animais Recém-Nascidos , Teorema de Bayes , Colostro , Feminino , Gravidez , Refratometria/veterinária
15.
Anim Sci J ; 92(1): e13543, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33738872

RESUMO

This study aims to evaluate the effect of puerarin on performance, meat quality, and serum indexes of beef cattle under hot environment. Thirty-two bulls were divided into four groups and fed diet supplemented with puerarin at 0, 200, 400, or 800 mg/kg. Results showed that heat stress was employed for 54 out of 60 days, 400 mg/kg group declined serum cortisol (COR) contents, all treatments increased the contents of total cholesterol, high density lipoprotein cholesterol, and total superoxide dismutase activity; in addition, glutathione peroxidase activity of 200 mg/kg group were enhanced, only 800 mg/kg group enhanced immunoglobulin (IgA, IgM, and IgG) and low density lipoprotein cholesterol contents compared with the control (p < .05). Moreover, 400-mg/kg puerarin increased serum growth hormone levels compared with 200 mg/kg group but declined COR concentrations compared with 200 mg/kg and 800 mg/kg groups (p < .05). More importantly, average daily gain and daily matter intake, and intramuscular fat contents of 400 mg/kg group were enhanced, but the shear force of beef in 400 mg/kg and 800 mg/kg groups were declined compared with the control (p < .05). These findings indicated that supplemental with puerarin enhanced immune and antioxidant, and 400 mg/kg of puerarin improved performance and meat quality by normalizing levels of stress hormones and increasing intramuscular fat deposition of beef cattle under hot environment.


Assuntos
Bovinos/crescimento & desenvolvimento , Bovinos/metabolismo , Dieta/veterinária , Suplementos Nutricionais , Exposição Ambiental/efeitos adversos , Qualidade dos Alimentos , Resposta ao Choque Térmico/efeitos dos fármacos , Temperatura Alta/efeitos adversos , Isoflavonas/administração & dosagem , Isoflavonas/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Carne Vermelha , Animais , Antioxidantes/metabolismo , Bovinos/imunologia , Hormônio do Crescimento/metabolismo , Hidrocortisona/metabolismo , Imunoglobulinas/metabolismo , Masculino
16.
Front Immunol ; 12: 627173, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33777010

RESUMO

Mucosal-associated invariant T (MAIT) cells are a population of innate-like T cells that utilize a semi-invariant T cell receptor (TCR) α chain and are restricted by the highly conserved antigen presenting molecule MR1. MR1 presents microbial riboflavin biosynthesis derived metabolites produced by bacteria and fungi. Consistent with their ability to sense ligands derived from bacterial sources, MAIT cells have been associated with the immune response to a variety of bacterial infections, such as Mycobacterium spp., Salmonella spp. and Escherichia coli. To date, MAIT cells have been studied in humans, non-human primates and mice. However, they have only been putatively identified in cattle by PCR based methods; no phenotypic or functional analyses have been performed. Here, we identified a MAIT cell population in cattle utilizing MR1 tetramers and high-throughput TCR sequencing. Phenotypic analysis of cattle MAIT cells revealed features highly analogous to those of MAIT cells in humans and mice, including expression of an orthologous TRAV1-TRAJ33 TCR α chain, an effector memory phenotype irrespective of tissue localization, and expression of the transcription factors PLZF and EOMES. We determined the frequency of MAIT cells in peripheral blood and multiple tissues, finding that cattle MAIT cells are enriched in mucosal tissues as well as in the mesenteric lymph node. Cattle MAIT cells were responsive to stimulation by 5-OP-RU and riboflavin biosynthesis competent bacteria in vitro. Furthermore, MAIT cells in milk increased in frequency in cows with mastitis. Following challenge with virulent Mycobacterium bovis, a causative agent of bovine tuberculosis and a zoonosis, peripheral blood MAIT cells expressed higher levels of perforin. Thus, MAIT cells are implicated in the immune response to two major bacterial infections in cattle. These data suggest that MAIT cells are functionally highly conserved and that cattle are an excellent large animal model to study the role of MAIT cells in important zoonotic infections.


Assuntos
Infecções Bacterianas/imunologia , Bovinos/imunologia , Células T Invariantes Associadas à Mucosa/imunologia , Animais , Citocinas/farmacologia , Feminino , Antígenos de Histocompatibilidade Classe I/imunologia , Humanos , Masculino , Camundongos , Antígenos de Histocompatibilidade Menor/imunologia , Fenótipo , Ribitol/análogos & derivados , Ribitol/farmacologia , Uracila/análogos & derivados , Uracila/farmacologia
17.
Mol Immunol ; 132: 53-59, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33545625

RESUMO

Neospora caninum is a leading cause of abortion in cattle worldwide. The study of the immune response against N. caninum is critical to understand its epidemiology, pathogenesis, diagnosis and, ultimately, in preventing and controlling bovine neosporosis. Herein, we determined the gene expression of innate immune components endosomal RNA-sensing TLRs, BMAP28 cathelicidin, TNF-α and IL-10 and characterized the variation in both IgG ratio and avidity at delivery in N. caninum-infected heifers challenged at day 210 of gestation, colostrum and their calves. Increased BMAP28 expression was observed not only in colostrum but also in peripheral blood mononuclear cells (PBMC) and umbilical cord of calves from N. caninum-infected heifers in comparison with mock-infected control group. In addition, statistically significant decrease of TLR7 and IL-10 expression levels were observed in umbilical cord, suggesting an attempt to avoid an exacerbated immune response against the parasite. At delivery, serum and colostrum samples from infected group evidenced specific IgG anti-N. caninum. Infected heifers showed IgG1/IgG2 ratios <1 and high avidity specific IgG. As expected, colostrum samples of these animals exhibited a high IgG1 concentration and elevated avidity values. Three out of four calves from N. caninum-infected heifers had specific IgG with IgG1/IgG2 ratios>1 and lower avidity values before colostrum intake. Interestingly, both IgG1/IgG2 ratios and avidity values increased in seropositive calves after colostrum intake. Overall, this study provides novel information on neonatal immunity in congenitally infected calves, which is essential to understand how the immune pathways could be manipulated or immune components could be employed in order to improve protection against neosporosis.


Assuntos
Bovinos/imunologia , Colostro/imunologia , Regulação da Expressão Gênica no Desenvolvimento/imunologia , Imunidade Humoral , Imunidade Inata , Neospora/imunologia , Receptores Toll-Like/metabolismo , Animais , Anticorpos Antiprotozoários/imunologia , Bovinos/embriologia , Bovinos/metabolismo , Bovinos/parasitologia , Doenças dos Bovinos/genética , Doenças dos Bovinos/imunologia , Doenças dos Bovinos/metabolismo , Doenças dos Bovinos/parasitologia , Feminino , Imunoglobulina G/imunologia , Interleucina-10/genética , Interleucina-10/metabolismo , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Gravidez , Proteínas/genética , Proteínas/metabolismo , Receptor 7 Toll-Like/genética , Receptor 7 Toll-Like/metabolismo , Receptores Toll-Like/genética , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Cordão Umbilical/metabolismo
18.
Vet Med Sci ; 7(3): 876-887, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33502117

RESUMO

The present study investigated the effects of overripe pulp and green peel extract and powder of banana fruit (Musa. cavendish) on haematological, biochemical, immunological, health, and performance of Holstein dairy calves. In all, 40 newborn calves were randomly divided into four groups of 10 animals. In the control group, animals received no banana meal. In group 1, calves were supplemented with 2 g (dry matter)/kg body weight/day of overripe banana pulp extract. The calves in group 2 were supplemented with 1 g (dry matter) of overripe banana pulp extract/kg body weight/day and 1 g (dry matter) of green banana peel extract/kg body weight/day. The animals in group 3 were supplemented with 2 g/kg body weight/day of green banana peel powder. The feeding period of calves on the tested supplements was 5 days. Blood samples and other evaluations were taken on day 0 (at birth, before supplementation) and on days 7, 15 and 30. Just a trend towards better average daily weight gain was seen in groups 2 and 3 than others (p = 0.073). Significant group and sampling time interactions were seen for the quantities of RBC (group 1 was lower than other groups at day 30), MCV (group 3 was lower than other groups at day 30) and MCH (group 1 was higher than other groups at day 30) (p < 0.05). A trend towards significance in values of IgG (group 1 was lower than other groups at days 15 and 30) and bilirubin (higher values at day 7 in groups 1 and 2 than control, higher amounts at days 15 and 30 in groups 3 and 2 than control, respectively) was also observed. In conclusion, banana supplementation in neonatal calves had beneficial effects on the values of RBC, MCV, MCH, bilirubin, IgG and average daily weight gain in dairy calves.


Assuntos
Bovinos/fisiologia , Imunidade/efeitos dos fármacos , Musa/química , Extratos Vegetais/metabolismo , Ração Animal/análise , Animais , Análise Química do Sangue/veterinária , Bovinos/sangue , Bovinos/crescimento & desenvolvimento , Bovinos/imunologia , Dieta/veterinária , Suplementos Nutricionais/análise , Relação Dose-Resposta a Droga , Frutas/química , Testes Hematológicos/veterinária , Extratos Vegetais/administração & dosagem , Pós , Distribuição Aleatória
19.
Vet Immunol Immunopathol ; 232: 110182, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33401107

RESUMO

The objective of this study was to evaluate the associations of serum markers for systemic inflammation, liver, mineral, and energy status, and blood neutrophil counts with the function of circulating neutrophils in postpartum dairy cows. Blood samples were collected from 21 healthy Holstein cows at 5, 10, 14, and 21 d postpartum. Serum samples were used to measure concentrations of total calcium, phosphorus, magnesium, total protein, albumin, globulin, cholesterol, urea, glucose, gamma-glutamyl transferase, aspartate aminotransferase, glutamate dehydrogenase, haptoglobin (Hp), ß-hydroxybutyrate, non-esterified fatty acids (NEFA), and insulin-like growth factor-1. The shift of percentage of activated neutrophils for phagocytosis (PPC) and oxidative burst (POB) and the median fluorescence intensity (MFI) for PC (MFIPC), OB (MFIOB), and endocytic and proteolytic degradation measured via DQ-ovalbumin (MFIDQ) were evaluated using flow cytometry. Mixed linear regression models were used to assess the associations of serum concentrations of metabolites and blood neutrophil counts with each neutrophil function assay outcome accounting for d postpartum, parity, and body condition score. Pearson correlation tests (r) were used to describe the relationships of metabolites and neutrophil counts with neutrophil function assays that were significant in the regression models. Greater serum concentrations of Hp were associated with lesser OB function (POB and MFIOB; r = -0.2 for both), but greater PPC and MFIDQ (r = 0.3 for both). Greater serum NEFA and cholesterol were associated with lesser (r = -0.3) and greater (r = 0.2) POB function, respectively. Blood neutrophil counts were associated with PPC (r = -0.2) and MFIDQ (r = -0.3). At 5 d postpartum, greater serum total protein was associated with greater OB function (POB and MFIOB; r = 0.4 for both). Other markers were not associated with neutrophil function. Some metabolic and inflammatory markers in healthy postpartum dairy cows were associated with circulating neutrophil function. However, these associations only explained a small proportion of the variance in neutrophil function. Serum Hp concentration was most associated with neutrophil function changes but had opposite directions of association with OB- and PC-related functions. Future studies should focus on understanding the mechanisms by which Hp and other metabolic indicators affect neutrophil function in healthy and diseased postpartum dairy cows.


Assuntos
Biomarcadores/sangue , Bovinos/imunologia , Neutrófilos/imunologia , Animais , Feminino , Haptoglobinas/metabolismo , Contagem de Leucócitos/veterinária , Período Pós-Parto
20.
Am J Reprod Immunol ; 85(5): e13365, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33099841

RESUMO

PROBLEM: The oviduct is essential for reproduction. We previously showed that oviduct epithelial cells (OECs) isolated from aged cows expressed higher levels of inflammatory cytokines, including interleukin (IL) 1A and IL1B. In addition, aging is associated with tissue dysfunction and cellular senescence via a senescence-associated secretory phenotype (SASP) and immune cell accumulation. We investigated whether IL1A or IL1B causes SASP production, cellular senescence, and inflammatory responses in bovine OECs. METHOD OF STUDY: The OECs were isolated from bovine oviducts from young (mean 50.3 months) and aged cows (mean 157.0 months) and cultured. RESULTS: Treatment with IL1A or IL1B induced SASP production (IL8, IL6, TNFA, and CCL2) and mRNA expression of cell adhesion molecules in bovine OECs, but both IL1s did not induce cellular senescence in OECs and migration of polymorphonuclear neutrophils (PMNs). Cultured medium of OECs treated with IL1s, especially IL1B, dramatically induced PMN migration. Treatment with the CCL2 inhibitor, but not IL8 or its receptor CXCR2 inhibitors, significantly reduced immune cell migration in IL1B-treated OEC-cultured medium. Treatment with IL1B increased PMN adhesion to OECs, resulting in further SASP production in OECs due to a PMN-OEC interaction. CONCLUSION: We suggest that senescence-associated IL1s cause SASP production in bovine OECs and CCL2 induced by IL1B is essential for the migration of immune cells to OECs. Specifically, IL1B regulates PMN migration and adhesion to bovine OECs, and PMNs accelerate inflammatory cytokine production from bovine OECs via a direct interaction. These phenomena may contribute to chronic oviductal inflammation, resulting in subfertility.


Assuntos
Bovinos/imunologia , Citocinas/imunologia , Células Epiteliais/imunologia , Neutrófilos/imunologia , Oviductos/imunologia , Animais , Células Cultivadas , Senescência Celular , Quimiotaxia , Técnicas de Cocultura , Citocinas/genética , Feminino , Neutrófilos/fisiologia
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