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1.
Acta Vet Scand ; 61(1): 38, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31391084

RESUMO

Canine leishmaniosis is a disease caused by Leishmania infantum, a vector-borne parasite. Due to the zoonotic potential of canine leishmaniosis, infected dogs must be identified. Serological assays are the most common methods for the detection of L. infantum infection in dogs used in veterinary practice. The aim of the study was to assess the performance of a rapid immunochromatographic test (FASTest LEISH®, MEGACOR Diagnostik) for the detection of specific antibodies to that of the L. infantum in dog sera. The results were simultaneously compared using a commercial brand of indirect immunofluorescence antibody test and an in-house enzyme-linked immunosorbent assay as references. Between the two reference tests, 232 serum samples out of 244, produced concordant results while 12 exhibited discordant results. Of the 232 concordant samples, 121 were classified as L. infantum seropositive, and 111 samples were previously classified as L. infantum seronegative by a combination of the reference assays. All samples that were seropositive by the reference tests were also positive according to the rapid test, and only one sample that was seronegative according to the two reference assays was positive according to the rapid test. Compared with the reference tests, the rapid test sensitivity was 100%, specificity was 99.1%, accuracy was 99.6%, Cohen's kappa coefficient was 0.99, and the area under receiver operating characteristic curve was 0.995. The FASTest LEISH® is a rapid, qualitative in-clinic test with high sensitivity and specificity.


Assuntos
Anticorpos Antiprotozoários/sangue , Doenças do Cão/diagnóstico , Ensaio de Imunoadsorção Enzimática/veterinária , Técnica Indireta de Fluorescência para Anticorpo/veterinária , Imunoensaio/veterinária , Leishmaniose Visceral/veterinária , Animais , Doenças do Cão/sangue , Cães , Leishmania infantum , Leishmaniose Visceral/sangue , Leishmaniose Visceral/diagnóstico , Sensibilidade e Especificidade
2.
BMC Vet Res ; 15(1): 274, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31370852

RESUMO

BACKGROUND: In Poland, the leader in goose production in Europe, goose parovirus infection, or Derzsy's disease (DD), must be reported to the veterinary administration due to the serious economic and epizootic threat to waterfowl production. Prophylactic treatment for DD includes attenuated live or inactivated vaccines. Moreover, the control of DD includes the monitoring of maternal derived antibody (MDA) levels in the offspring and antibody titers in the parent flock after vaccination. The aim of this study was to develop an ELISA for the detection of goose parvovirus (GPV) antibodies. RESULTS: Two recombinant protein fragments derived from VP3 (viral protein 3) GPV, namely VP3ep6 and VP3ep4-6 with a mass of 20.9 and 32.3 kDa, respectively, were produced using an Escherichia coli expression system. These proteins were purified by one-step nickel-affinity chromatography, which yielded protein preparations with a purity above 95%. These recombinant proteins were useful in the detection of serum anti-GPV antibodies, and this was confirmed by Western blotting. However, recombinant VP3ep4-6 protein showed a greater ability to correctly identify sera from infected geese. In the next stage of the project, a pool of 166 goose sera samples, previously examined by a virus neutralization test (VN), was tested. For further studies, one recombinant protein (VP3ep4-6) was selected for optimization of the test conditions. After optimization, the newly developed ELISA was compared to other serological tests, and demonstrated high sensitivity and specificity. CONCLUSION: In conclusion, the VP3ep4-6 ELISA method described here can be used for the detection of antibodies to GPV in serum.


Assuntos
Anticorpos Antivirais/sangue , Proteínas do Capsídeo/imunologia , Ensaio de Imunoadsorção Enzimática/veterinária , Infecções por Parvoviridae/veterinária , Parvovirinae/imunologia , Doenças das Aves Domésticas/diagnóstico , Animais , Ensaio de Imunoadsorção Enzimática/normas , Infecções por Parvoviridae/sangue , Infecções por Parvoviridae/diagnóstico , Doenças das Aves Domésticas/sangue , Doenças das Aves Domésticas/virologia , Proteínas Recombinantes/imunologia , Sensibilidade e Especificidade
3.
Prev Vet Med ; 169: 104697, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31311638

RESUMO

Malignant theileriosis of sheep and goats caused by Theileria lestoquardi is considered to be among the most important tick borne diseases in the Sudan. Information on the prevalence of the disease in different parts of the Sudan is limited. The purpose of this study was to estimate the prevalence of the disease in five states of the Sudan using molecular and serological assays. A total of 393 blood and serum samples from clinically asymptomatic sheep were analysed using nested reverse line blot (nRLB) and loop mediated isothermal amplification (LAMP), as well as an enzyme-linked immunosorbent assay (ELISA). The results indicated a sero-prevalence of 33.8% while RLB and LAMP assays revealed molecular prevalences of 29.5 and 22.6% respectively. The prevalence of Theileria lestoquardi varied significantly according to the geographical origin of the infected animals, whereas age and gender did not have a significant effect. RLB data indicated that T. lestoquardi usually occurred as a co-infection with the non-pathogenic Theileria ovis. Using RLB as a gold standard, a sensitivity of 68.1% and a specificity of 96.4% were recorded for LAMP and a sensitivity of 75.9% and a specificity of 83.8% for ELISA. The Kappa coefficient between nRLB and LAMP indicated a significant level of agreement (0.692), but only moderate concordance (0.572) between nRLB and ELISA. The results of the present study confirm and extend earlier findings regarding the widespread of T. lestoquardi infections in sheep in the Sudan. The data provide evidence that should enable the veterinary authorities to deploy appropriate control measures.


Assuntos
Doenças dos Ovinos/epidemiologia , Doenças dos Ovinos/parasitologia , Theileria/isolamento & purificação , Theileriose/epidemiologia , Animais , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Geografia , Masculino , Reação em Cadeia da Polimerase/veterinária , Prevalência , Ovinos , Doenças dos Ovinos/sangue , Sudão/epidemiologia , Theileriose/sangue
4.
Prev Vet Med ; 169: 104698, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31311644

RESUMO

There is limited knowledge of the true prevalence and distribution of coxiellosis in dairy and beef cattle populations in Australia. For this to occur, apparent prevalence estimates need to be reliably adjusted, accounting for diagnostic sensitivity (DSe) and diagnostic specificity (DSp) of the test used. However, there are few tests available with known diagnostic specifications suitable to inform screening and surveillance activities in the Australian context. We initially modified and optimised a human indirect immunofluorescence assay (IFA) test for the detection of IgG antibodies against phase I and/or phase II Coxiella burnetii in bovine sera and determined an optimal screening dilution cut-off to be 1:160. Direct comparison of the modified IFA with the commercial IDEXX enzyme-linked immunosorbent assay (ELISA) kit (Q Fever Ab Test IDEXX Laboratories, United States of America) was performed by testing 458 serum samples from four distinct cattle populations across the east coast of Australia and New Zealand. Cross classified test results were then analysed using Bayesian latent class modelling, to validate the tests in the absence of a gold standard reference test. Results from this analysis indicate that the IFA, at a 1:160 serum dilution, has an estimated DSe of 73.6% (95% Credible Interval (CrI) 61.1, 85.9) and DSp of 98.2% (95% CrI 95.1, 99.7). The commercial IDEXX ELISA kit was found to have a higher DSe of 87.9% (95% CrI 73.9, 96.4) and similar DSp of 97.7% (95% CrI 93.2, 99.7). Evaluation of the diagnostic performance of the IFA and ELISA methods, specifically for use in cattle will enable more accurate interpretation of prevalence estimates of C. burnetii exposure to be reported for cattle in Australia and other countries.


Assuntos
Anticorpos Antibacterianos/isolamento & purificação , Doenças dos Bovinos/diagnóstico , Doenças dos Bovinos/microbiologia , Coxiella burnetii/isolamento & purificação , Técnica Indireta de Fluorescência para Anticorpo/veterinária , Febre Q/veterinária , Animais , Austrália , Teorema de Bayes , Bovinos , Doenças dos Bovinos/sangue , Coxiella burnetii/imunologia , Ensaio de Imunoadsorção Enzimática/veterinária , Técnica Indireta de Fluorescência para Anticorpo/normas , Imunoglobulina G/sangue , Nova Zelândia , Febre Q/sangue , Febre Q/diagnóstico , Sensibilidade e Especificidade
5.
Prev Vet Med ; 169: 104712, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31311647

RESUMO

Surra is a zoonotic disease caused by Trypanosoma evansi, affecting the health and production of the livestock significantly. There are several methods to diagnose this disease, which have different principles, sensitivity, and specificity. Among them, the serological techniques using T. evansi as antigen are powerful tools for its epidemiological surveillance. However, they are poorly used due to inefficient in vitro propagation of T. evansi, which requires the use of laboratory animals for antigen production. In the present study, whole cell lysate of T. brucei brucei propagated in vitro was used as an antigen for the detection of anti-T. evansi immunoglobulin G in cattle through an indirect-ELISA. Based on a total of 45 samples from non-infected and 45 samples from T. evansi infected cattle, the sensitivity and specificity were estimated as 100% and 97.7%, respectively. After the validation, serological and molecular surveys were carried out in 710 cattle samples from two endemic Colombian regions (Antioquia and Arauca departments) for T. evansi where molecular prevalences of ˜7.0% were detected through the year and sporadic outbreaks of T. vivax infections have been associated to low prevalence of this species (<1%). A total of 424 (59.7%) samples were positive by indirect-ELISA T. b. brucei, while PCR test for T. evansi and T. vivax, showed 49 (6.9%) and no positive samples, respectively. Interestingly, categories of animals aged>1 year, Bos taurus breed, and those raised under intensive farming system exhibited a higher seroprevalence to T. evansi (P < 0.05). The results displayed a new alternative for antibody detection anti-T. evansi in livestock, using parasites propagated in vitro as antigen, which presents the advantage of higher standardization potential, and avoid the use of live animal for antigen production. A larger availability of this ELISA will generate useful information for a better understanding of the epidemiologic aspects, as well as for the management and control of these diseases in Colombia. However, the ability of the test to detect and/or cross react with T. vivax infections remains to be investigated.


Assuntos
Antígenos de Protozoários/isolamento & purificação , Ensaio de Imunoadsorção Enzimática/veterinária , Reação em Cadeia da Polimerase/veterinária , Trypanosoma brucei brucei/isolamento & purificação , Animais , Bovinos , Colômbia , Ensaio de Imunoadsorção Enzimática/métodos , Imunoglobulina G , Gado , Reação em Cadeia da Polimerase/métodos
6.
Vet Immunol Immunopathol ; 213: 109886, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31307667

RESUMO

The diagnosis of the early stages of paratuberculosis, caused by Mycobacterium avium subsp. paratuberculosis (Map), is a cumbersome task. In this study, an experimental Map-infection model of calves was used to improve the knowledge of early antibody response and to evaluate different in-house ELISAs in the detection of subclinical paratuberculosis. Calves were challenged with Map strain IS900-RFLPA (n = 3) or Map strain IS900-RFLPC (n = 2) (Argentinean isolated strains) or mock infected (n = 3), and their specific humoral response was evaluated. The diagnostic ELISA (IgG against Map protoplasmic antigen; PPA) could not detect the infection throughout the experimental period (180 days post-infection; dpi), whereas the IgG2/PPA-ELISA was able to identify infected calves at least once during the experiment. In addition, the use of crude Map extract detected most of the infections from 60 dpi onwards. Antibodies were also characterized by immunoblot: IgG2-reactivity to antigens of molecular weight lower than 50 kDa was detected in all infected calves. The experimental Map-infection model of calves used allows the study of the early humoral immune response in paratuberculosis. The evaluation of IgG2 specific to antigens lighter than 50 kDa emerges as an interesting alternative in calves naturally infected with paratuberculosis.


Assuntos
Anticorpos Antibacterianos/sangue , Doenças dos Bovinos/imunologia , Imunidade Humoral , Imunoglobulina G/sangue , Mycobacterium avium subsp. paratuberculosis , Paratuberculose/imunologia , Fatores Etários , Animais , Bovinos , Doenças dos Bovinos/microbiologia , Ensaio de Imunoadsorção Enzimática/veterinária , Fezes/microbiologia , Masculino , Fatores de Tempo
7.
Rev Bras Parasitol Vet ; 28(2): 203-209, 2019 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-31188948

RESUMO

Livestock infections by Trypanosoma vivax have been occurring with increasing frequency, mainly due to the presence of animals with subclinical infections and without apparent parasitaemia, making diagnosis challenging. The aim of the present study was to evaluate several techniques used for T. vivax diagnosis in order to assess the best way of using them during the course of the disease. Molecular methods demonstrated higher rates of detection than parasitological methods, detecting 33 of the 54 (61.1%) known positive samples, while the hematocrit centrifugation technique (best parasitological test) detected only 44.4%. The serological methods, IFAT and ELISA, detected seropositivity in 51 of the 54 (94.4%) and 49 of the 54 (90.7%) known positive samples, respectively. Despite being highly sensitive, the latter only demonstrates exposure to the infectious agent and does not indicate whether the infection is active. The present study was the first to use the qPCR for a South American isolate, improving disease detection and quantification. Furthermore, the analyses revealed that the patent phase of the disease may extend up to 42 days, longer than previously reported. The combination of several diagnostic techniques can lower the frequency of false negative results and contributes toward better disease control.


Assuntos
Ensaio de Imunoadsorção Enzimática/veterinária , Técnica Indireta de Fluorescência para Anticorpo/veterinária , Trypanosoma vivax , Tripanossomíase Africana/diagnóstico , Animais , Bovinos , Trypanosoma vivax/genética , Trypanosoma vivax/imunologia , Tripanossomíase Africana/veterinária
8.
Rev Bras Parasitol Vet ; 28(2): 215-220, 2019 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-31215607

RESUMO

Our objective was to identify the direct and indirect presence of Neospora caninum in dairy cattle and their aborted fetuses from Lima, Peru. A total 219 blood samples obtained from dairy cattle with records of spontaneous abortion were collected to detect antibodies against N. caninum in serum with indirect ELISA and search for risk-factor associations. 68 fetal aborted tissue samples of these cows were analyzed by PCR, indirect ELISA and histopathology assay to detect N. caninum presence. The prevalence ratio (PR) and 95% confidence intervals (CI) were estimated. Univariate analysis was performed using the chi-squared test. Among the 68 aborted fetuses collected, 10 (15%) were positive in at least two diagnostic tests. Among 219 serum samples, 46.6% (95% CI: 40.0%-53.3%) were positive. Cows with 4 years or older (PR: 7.10; 95% CI: 4.89-10.67) and multiparous (PR: 1.76; 95% CI: 1.11-2.80) were found to be more likely to possess N. caninum antibodies. This study detects presence of N. caninum in dairy cattle and their aborted fetus from Lima valley, suggesting biosecurity management improve to neosporosis control.


Assuntos
Aborto Animal/epidemiologia , Anticorpos Antiprotozoários/sangue , Doenças dos Bovinos/epidemiologia , Coccidiose/veterinária , Neospora , Aborto Animal/parasitologia , Animais , Bovinos , Doenças dos Bovinos/parasitologia , Coccidiose/complicações , Coccidiose/epidemiologia , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Neospora/genética , Neospora/imunologia , Peru/epidemiologia , Reação em Cadeia da Polimerase/veterinária , Gravidez , Fatores de Risco , Estudos Soroepidemiológicos
9.
Rev Bras Parasitol Vet ; 28(2): 245-257, 2019 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-31215610

RESUMO

This is a cross-sectional study to assess the presence of antibodies in ruminants against selected pathogens associated with reproductive disorders in cattle in four Brazilian states, including the zoonotic agent Coxiella burnetii. The used tests were Virus Neutralization Assay for IBR and BVD, Microscopic Agglutination Test for Leptospira spp., Indirect Fluorescent Antibody Test (IFAT) for C. burnetii and Toxoplasma gondii, and Enzyme-Linked Immunosorbent Assay for Neospora caninum and Trypanosoma vivax. Seropositivity for C. burnetii was 13.7% with titers from 128 to 131,072; 57.8% for BoHV-1, with titers between 2 and 1,024; 47.1% for BVDV-1a, with titers from 10 to 5,120; 89.2% for N. caninum; 50% for T. vivax; and 52.0% for Leptospira spp., with titers between 100 to 800 (the following serovars were found: Tarassovi, Grippotyphosa, Canicola, Copenhageni, Wolffi, Hardjo, Pomona and Icterohaemorrhagiae); 19.6% for T. gondii with titer of 40. This is the first study that has identified C. burnetii in cattle associated with BoHV and BVDV, N. caninum, Leptospira spp., T. gondii and T. vivax. Thus, future studies should be conducted to investigate how widespread this pathogen is in Brazilian cattle herds.


Assuntos
Doença das Mucosas por Vírus da Diarreia Viral Bovina/complicações , Doenças dos Bovinos/epidemiologia , Coccidiose/veterinária , Leptospirose/veterinária , Febre Q/veterinária , Toxoplasmose Animal/complicações , Tripanossomíase Africana/veterinária , Aborto Animal , Testes de Aglutinação , Animais , Doença das Mucosas por Vírus da Diarreia Viral Bovina/diagnóstico , Doença das Mucosas por Vírus da Diarreia Viral Bovina/epidemiologia , Brasil/epidemiologia , Bovinos , Doenças dos Bovinos/microbiologia , Doenças dos Bovinos/parasitologia , Doenças dos Bovinos/virologia , Coccidiose/complicações , Coccidiose/diagnóstico , Coccidiose/epidemiologia , Coxiella burnetii/imunologia , Estudos Transversais , Vírus da Diarreia Viral Bovina/imunologia , Endometrite/etiologia , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Técnica Indireta de Fluorescência para Anticorpo/veterinária , Infertilidade Feminina/etiologia , Leptospira/imunologia , Leptospirose/complicações , Leptospirose/diagnóstico , Leptospirose/epidemiologia , Neospora/imunologia , Febre Q/complicações , Febre Q/diagnóstico , Febre Q/epidemiologia , Estudos Soroepidemiológicos , Toxoplasma/imunologia , Toxoplasmose Animal/diagnóstico , Trypanosoma vivax/imunologia , Tripanossomíase Africana/complicações , Tripanossomíase Africana/diagnóstico , Tripanossomíase Africana/epidemiologia
10.
BMC Vet Res ; 15(1): 202, 2019 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-31200717

RESUMO

BACKGROUND: Bovine viral diarrhea virus (BVDV) infects various ungulates and causes reproductive failure in infected goats. BVDV has been detected among goats in the Republic of Korea, but the route of transmission remains unclear. Here, we aimed to investigate whether BVDV-1b circulating among Korean cattle can be transmitted to Korean native goats (Capra aegagrus hircus) and characterize the outcomes of BVDV infection in these goats. RESULTS: Four goats were inoculated intranasally with the Korean noncytopathic (ncp) BVDV-1b strain. Two goats exhibited clinical signs of illness, including coughing and nasal discharge. Nasal swabs and blood were collected to screen for viral RNA and BVDV antibodies. Using the 5'-untranslated region (UTR), viral RNA was detected in the nasal swabs of two goats (Goat 1 and 3) on 12 day post-inoculation (dpi) and in the blood sample of one goat (Goat 1) on 7 and 19 dpi. Using the N-terminal protease (Npro) region, viral RNA was detected in the blood sample of Goat 1 on 7 and 12 dpi. Antibodies to BVDV were detected in Goats 1 and 3 on 16-21 dpi using enzyme-linked immunosorbent assay. Sequence analysis of the virus from nasal swabs and blood samples, which was detected via RT-PCR, using the 5'-UTR and Npro regions led to the identification of the strain as ncp BVDV-1b and revealed changes in the nucleotide sequence of these goats. CONCLUSIONS: Our results indicate that changes in the nucleotide sequence are associated with the establishment of BVDV infection in Korean native goats; these changes may be owing to a process required for the establishment of infection in a new host reservoir. Broadly, these findings highlight the importance of BVDV surveillance in ungulates other than cattle.


Assuntos
Vírus da Diarreia Viral Bovina Tipo 1/genética , Doenças das Cabras/virologia , Infecções por Pestivirus/veterinária , Regiões 5' não Traduzidas , Animais , Anticorpos Antivirais/sangue , Vírus da Diarreia Viral Bovina Tipo 1/imunologia , Vírus da Diarreia Viral Bovina Tipo 1/patogenicidade , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Doenças das Cabras/transmissão , Cabras , Mucosa Nasal/virologia , Infecções por Pestivirus/genética , Infecções por Pestivirus/virologia , RNA Viral/sangue , RNA Viral/genética , República da Coreia , Análise de Sequência de RNA
11.
J Dairy Sci ; 102(7): 6037-6046, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31056338

RESUMO

The use of the heterologous competitive strategy has become a vital method to improve the sensitivity of ELISA. In this work, we prepared an anti-enrofloxacin (ENR) mAb with ENR-bovine serum albumin (BSA) as immunogen. The molecular descriptors of quinolones were then used to screen heterologous coating antigens for the detection of ENR based on an ensemble learning method to improve the sensitivity of the ELISA. Results indicated that 6 of the 7 selected heterologous competitive antigens could enhance the sensitivity of ELISA. The ELISA sensitivity for the detection of ENR with sarafloxacin-BSA as heterologous coating antigen was improved 10-fold (in PBS) and 6-fold (in milk) compared with that with ENR-BSA as homologous antigen. The strategy can effectively screen suitable heterologous competitive antigens to improve the sensitivity of ELISA, followed by preparation of mAb with no additional modification to the corresponding immunogen.


Assuntos
Antibacterianos/análise , Enrofloxacina/análise , Ensaio de Imunoadsorção Enzimática/veterinária , Leite/química , Animais , Antibacterianos/imunologia , Antígenos Heterófilos/análise , Bovinos , Ciprofloxacino/análogos & derivados , Ciprofloxacino/análise , Enrofloxacina/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Soroalbumina Bovina
12.
Vet Immunol Immunopathol ; 211: 38-43, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31084892

RESUMO

Natural antibodies (NAb) are antibodies that can bind to a particular antigen without any apparent antigenic stimulation. In this paper, a careful analysis has been carried out on NAb levels in goat kid serum; possible correlations with the total immunoglobulin (tot-Ig) levels and specific antibody (SpAb) response were considered. Twenty randomly chosen kids were submitted to a first blood sampling (day 0). After 60 and 100 days, new blood samplings were carried out in the same animals. On day 0, after blood collection, all animals were immunized with a commercial vaccine; the immunization was repeated 30 days apart. Some exogenous antigens were tested to verify their immunoreactivity to NAb. Among them, the synthetic hapten 2,4,6-trinitrophenyl (TNP) conjugated with bovine serum albumin, resulted as the antigen with the higher immunoreactivity to NAb. Tot-Ig levels increased over time (p < 0.001). On the contrary, NAb levels, both IgG- and IgM-isotypes, significantly decreased during the experimental period (p < 0.001 and <0.05, respectively). Linear regression analyses showed a high correlation between IgM-NAb and tot-IgM levels (p < 0.001) at all the evaluated sampling times. However, a significant correlation between IgG-NAb and IgM-NAb was found only at the 1st (p < 0.01) and at the 2nd sampling (p < 0.05). No significant correlations were found between SpAb response and the other assessed humoral immune parameters. The obtained results are discussed in the light of the possible use of NAb assessment for the evaluation of the immune system activity in goat.


Assuntos
Imunidade Adaptativa/imunologia , Anticorpos/imunologia , Cabras/imunologia , Imunoglobulinas/imunologia , Animais , Anticorpos/sangue , Formação de Anticorpos/imunologia , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Cabras/sangue , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Imunoglobulina M/sangue , Imunoglobulina M/imunologia , Imunoglobulinas/sangue , Masculino
13.
BMC Vet Res ; 15(1): 149, 2019 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-31096976

RESUMO

BACKGROUND: The objective of this study was to determine the sensitivity (Se) and specificity (Sp) of bovine tuberculosis (bTB) screening tests including a single intradermal tuberculin (SIT) test, interferon gamma (IFN-γ) assay, and a commercial ELISA test (M. bovis Ab) in dairy cattle, under field conditions, using a Bayesian approach. RESULTS: The study population consisted of 128 dairy cows from 25 bTB-infected herds in Chiang Mai and Chiang Rai provinces, Thailand. A single-population Bayesian model was implemented assuming conditional dependence between the SIT test and IFN-γ assays. The 95% posterior probability interval (PPI) of the SIT test (severe interpretation) Se ranged from 75.3 to 95.2% (median = 87.6%), while the Sp was slightly lower (median = 83.6%, PPI = 74.2-92.8%). The IFN-γ assay Se was moderate and the 95% PPI ranged from 38.6 to 74.4% (median = 55.7%) with higher Sp (median = 93.5.4%, PPI = 87.0-98.1%). The M. bovis Ab ELISA Se was low, with 95% PPI ranging between 30.0 and 71.2% (median = 47.4%); however, the Sp was high (median = 90.9%, PPI = 84.5-95.5%). CONCLUSION: The SIT test sensitivity was similar to that demonstrated in other regions and can, therefore, be used effectively as part of control programs in this area. The IFN-γ and M. bovis Ab ELISA assays can be applied as supplementary techniques. The test performance of these tests when used as single tests without confirmation, however, are expected to continue to challenge disease eradication efforts.


Assuntos
Ensaio de Imunoadsorção Enzimática/veterinária , Interferon gama/análise , Teste Tuberculínico/veterinária , Tuberculose Bovina/diagnóstico , Animais , Teorema de Bayes , Bovinos , Indústria de Laticínios , Testes Diagnósticos de Rotina/veterinária , Feminino , Mycobacterium bovis , Sensibilidade e Especificidade , Tailândia
14.
BMC Vet Res ; 15(1): 177, 2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-31138202

RESUMO

BACKGROUND: Peste des petits ruminants (PPR) is a severe infectious disease in both domestic and wild small ruminants. Due to its heavy economic burden and hence social and health impacts on human populations, Food and Agriculture Organization of the United Nations (FAO) and The World Organization for Animal Health (OIE) have targeted PPR for eradication by 2030. In order to plan and implement a successful eradication program, factual status assessments prior to devising disease control strategies is a vital criterion. The aim of this study was to isolate and characterize PPR virus from a rising wave of outbreaks in southern Iran. RESULTS: Twenty-one clinical samples, including blood as well as oral, nasal and ocular swabs were collected from ten sick animals in 4 various herds and were examined with ELISA and RT-PCR for the presence of PPR virus antigen and genome, respectively. The virus was successfully isolated in primary lamb kidney cell culture and identified by RT-PCR. Phylogenetic analysis of the sequenced N genes revealed that, while the earliest reports of Iran's outbreaks were grouped into clusters with Saudi Arabia, Turkey and Africa, in this study reported sequences were grouped with samples from Pakistan, Tajikistan and China in particular. This observation suggests a shift in PPRV flow from the western borders of the country to the eastern neighboring countries. CONCLUSIONS: Lineage IV of PPR virus is presently circulating in Iran, with certain levels of genetic diversity. Present study along with previous reports demonstrates the dispersal patterns and movements of PPR virus, which highlights the reversal pattern of virus flow in recent years. Such information is necessary to understand PPRV molecular epidemiology and to develop more proper control strategies to eradicate the disease in the planned time.


Assuntos
Surtos de Doenças/veterinária , Peste dos Pequenos Ruminantes/epidemiologia , Vírus da Peste dos Pequenos Ruminantes/genética , Animais , Antígenos Virais/análise , Células Cultivadas , Ensaio de Imunoadsorção Enzimática/veterinária , Genoma Viral , Doenças das Cabras/epidemiologia , Doenças das Cabras/virologia , Cabras , Irã (Geográfico)/epidemiologia , Peste dos Pequenos Ruminantes/virologia , Vírus da Peste dos Pequenos Ruminantes/isolamento & purificação , Filogenia , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Ovinos , Doenças dos Ovinos/epidemiologia
15.
Top Companion Anim Med ; 35: 42-46, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31122687

RESUMO

Microscopic methods which employ active or passive flotation have been used to detect parasite diagnostic stages in the feces of companion animals for many years. More recently, coproantigen ELISAs for the detection of excretory/secretory products from intestinal nematodes have been introduced. These assays can identify the presence of parasites when eggs are not recovered by flotation (e.g. prepatent infection or intermittent egg shedding). The study was designed to assess the added benefit of these coproantigen tests in canine fecal diagnostics. The work was performed at 3 separate sites where canine fecal samples were each independently evaluated by both centrifugal flotation with an expert examiner (CFE) and passive flotation with a less experienced examiner. All samples were also tested using coproantigen ELISA to detect ascarid, hookworm, or whipworm antigen (IDEXX Laboratories, Inc, Westbrook, Maine). A total of 1202 samples were collected; 626 were from shelter dogs and 576 were from pet dogs. CFE recovered ascarid eggs in 58 samples, hookworm eggs in 229 samples, and whipworm eggs in 95 samples. Of the positive samples identified by CFE, the PFE and ELISA identified 40 and 51 ascarid samples, 188 and 203 hookworm samples, and 65 and 67 whipworm positive samples, respectively. The coproantigen ELISA identified 8 ascarid, 82 hookworm, and 22 whipworm positive samples that were not detected by CFE. The combined results of passive flotation and the coproantigen ELISA improved the percent agreement with centrifugal flotation, suggesting that greater sensitivity of detection may be achieved through the use of complementary diagnostic methods. However, errors of misidentification and poor recovery apparently introduced by less experienced examiners using an inferior flotation method remained. A diagnostic approach that combines coproantigen assays with centrifugal flotation and examination by an expert allows detection of more ascarid, hookworm, and whipworm infections.


Assuntos
Antígenos de Helmintos/isolamento & purificação , Doenças do Cão/parasitologia , Nematoides/isolamento & purificação , Infecções por Nematoides/diagnóstico , Animais , Doenças do Cão/diagnóstico , Cães , Ensaio de Imunoadsorção Enzimática/veterinária , Fezes/química , Fezes/parasitologia , Nematoides/imunologia , Infecções por Nematoides/imunologia , Óvulo
16.
Vet Parasitol ; 269: 16-20, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31079822

RESUMO

Teladorsagia circumcincta is the dominant nematode of sheep in cool, temperate climates. Faecal nematode egg counts (FEC) are widely used to identify the intensity of infection and as a measure of host resistance to nematodes. However due to density-dependent effects on worm fecundity the relationship between FEC and worm burden is not linear. In addition collecting FEC data is challenging on a practical level and there is a need for more reliable markers of resistance. There are two major known mechanisms of immunity to T. circumcincta: IgE against third stage larvae (L3) and IgA against fourth stage larvae (L4), which inhibits parasite growth. In this study salivary IgA responses were measured in over 5000 animals against L3 antigen by Enzyme Linked Immunosorbent Assay (ELISA). Antigen-specific IgA levels were negatively correlated with FEC (r=-0.26, SE = 0.02) and were heritable (h2 = 0.16, SE = 0.04) indicating that they can be used to identify resistant animals suitable for inclusion in selective breeding programs. Antigen-specific IgA responses were not negatively correlated with muscle depth. Our analyses indicate that selection for T. circumcincta L3 antigen-specific IgA is possible without impacting on the production traits for the Lleyn breed.


Assuntos
Anticorpos Anti-Helmínticos/imunologia , Imunoglobulina A/imunologia , Ostertagia/imunologia , Doenças dos Ovinos/imunologia , Animais , Biomarcadores/análise , Cruzamento , Ensaio de Imunoadsorção Enzimática/veterinária , Fezes/parasitologia , Feminino , Contagem de Ovos de Parasitas/veterinária , Fenótipo , Saliva/imunologia , Ovinos , Doenças dos Ovinos/parasitologia
17.
N Z Vet J ; 67(5): 219-227, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31104579

RESUMO

Eradicating bovine viral diarrhoea (BVD) from cattle populations requires a clear approach for determining the epidemiological status of individual herds and implementing the appropriate control measures to ensure the transmission cycle is cost-effectively broken. This is particularly important in countries such as New Zealand where there is currently no coordinated national programme and the herd-level decisions to control BVD are left to the discretion of individual farmers and veterinarians. To ensure greater consistency in the information being delivered by different stakeholders, we review the epidemiology of BVD in the context of New Zealand pastoral production systems and provides a series of simplified recommendations for the future control of BVD in beef and dairy herds. Based on analysis of BVD test accession data from commercial diagnostic laboratories, it has been estimated that 40.6% of dairy herds and 45.6% of beef herds tested had positive results for antibodies to BVD virus. While BVD continues to remain widespread and under voluntary control in New Zealand, it is recommended that herds test all individual mixed-age cows and replacement heifers for BVD virus or antigen and remove persistently infected animals from the breeding population. All new breeding animals that have entered the herd either through purchase or birth should also be tested for BVD virus. Biosecurity risks should be managed by reducing contacts with other herds and implementing targeted vaccination programmes. All individual purchased cattle should be tested and confirmed negative for BVD virus before being moved onto the buyer's property, even if the herd of origin had a negative antibody-based screening test. Herds should continue annual antigen or virus testing of all calves as soon as possible after birth to identify any persistently infected animals.


Assuntos
Criação de Animais Domésticos/métodos , Doença das Mucosas por Vírus da Diarreia Viral Bovina/diagnóstico , Doença das Mucosas por Vírus da Diarreia Viral Bovina/prevenção & controle , Controle de Doenças Transmissíveis/métodos , Animais , Anticorpos Antivirais , Doença das Mucosas por Vírus da Diarreia Viral Bovina/epidemiologia , Doença das Mucosas por Vírus da Diarreia Viral Bovina/transmissão , Bovinos , Vírus da Diarreia Viral Bovina/isolamento & purificação , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Masculino , Nova Zelândia/epidemiologia , Gravidez , Vacinas Virais/uso terapêutico
18.
Parasitol Res ; 118(7): 2317-2323, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31144033

RESUMO

The laboratory diagnosis of visceral leishmaniasis (VL) presents limitations related to its sensibility and/or specificity. In this context, the aim of this study was to evaluate an enzyme-linked immunoassay to detect IgG antibodies against Leishmania infantum exo-antigens for diagnosis of VL, called ELISA-Exo. This assay was applied in 309 masked serum samples from VL, tegumentary leishmaniasis, Chagas disease, schistosomiasis mansoni, malaria patients, and healthy individuals. The results were compared with those from ELISA using rK39 as antigen (ELISA-rK39). The ELISA assays presented sensitivity of 96.8% and 98.4% (p = 0.68), specificity of 92.4% for both, and diagnostic accuracy of 94.2% and 94.8% (p = 0.48) by the ELISA-Exo and ELISA-rK39, respectively. An excellent agreement beyond chance (Kappa index = 0.82) was obtained when the results from ELISA assays were cross-tabulated. The Western blotting showed that false-positive results presented by ELISA-Exo probably were produced by cross-reactivity of antigens shared with the species of the family Trypanosomatidae. In the future, an immunoproteomic approach can contribute for identification of main immunoreactive L. infantum exo-antigens.


Assuntos
Antígenos de Protozoários/imunologia , Ensaio de Imunoadsorção Enzimática/veterinária , Leishmania infantum/imunologia , Leishmaniose Visceral/diagnóstico , Animais , Western Blotting , Reações Cruzadas , Confiabilidade dos Dados , Feminino , Humanos , Leishmania infantum/isolamento & purificação , Leishmaniose Visceral/parasitologia , Sensibilidade e Especificidade
19.
Vet Surg ; 48(5): 770-779, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31032990

RESUMO

OBJECTIVE: To determine the relationship between synovial biomarker concentrations and severity of lameness and to assess the ability to differentiate normal from osteoarthritic joints with synovial biomarker concentrations. STUDY DESIGN: Prospective clinical study. SAMPLE POPULATION: Twelve hounds with no evidence of osteoarthritis (OA) and 27 client-owned dogs with unilateral lameness and joint pain in a single joint from naturally occurring OA. METHODS: Enrollment in the OA group required a history of lameness, radiographic evidence of OA on orthogonal joint radiographs, and ≥6% gait asymmetry between contralateral limbs. The concentrations of 14 synovial OA biomarkers in synovial samples obtained after gait analysis were measured with enzyme-linked immunosorbent assays and compared between normal and OA joints. RESULTS: Concentrations of monocyte chemoattractant protein (MCP)-1, substance P, interleukin (IL)-6, IL-8, KC-like, matrix metalloproteinase (MMP)-1, and MMP-3 were greater (P ≤ .05) in OA than in normal joints. The concentrations of bradykinin and tissue inhibitors of metalloproteinase-4 were decreased in OA compared with normal joints. Monocyte chemoattractant protein 1 was identified as the most accurate marker to distinguish OA from normal joints. No correlation was detected between any OA biomarker concentration, individually or in combination, and severity of gait asymmetry at the walk. CONCLUSION: Differences in proinflammatory and anti-inflammatory biomarkers were detected between OA and normal joints, but no relationship was identified between biomarker concentrations and gait asymmetry in dogs with OA. CLINICAL IMPACT: This information will help guide future studies to elucidate how factors such as disease chronicity, severity, and etiology affect these relationships.


Assuntos
Citocinas/sangue , Citocinas/metabolismo , Doenças do Cão/metabolismo , Osteoartrite/veterinária , Líquido Sinovial/química , Animais , Biomarcadores/sangue , Biomarcadores/química , Doenças do Cão/sangue , Doenças do Cão/etiologia , Cães , Ensaio de Imunoadsorção Enzimática/veterinária , Coxeadura Animal/sangue , Coxeadura Animal/etiologia , Coxeadura Animal/metabolismo , Osteoartrite/sangue , Osteoartrite/complicações , Osteoartrite/metabolismo , Estudos Prospectivos
20.
Artigo em Alemão | MEDLINE | ID: mdl-30999350

RESUMO

A sufficient supply of colostral antibodies within the first hours of life is crucial for the development and the health status in young calves. It is rational to examine the immunoglobulin uptake of single animals, but particularly on a herd basis, during herd controls and consultations. This enables economical calf rearing in accordance with animal welfare. Because of the costly, laboratory-dependent and in part time-consuming direct measurement of the absorbed immunoglobulins using radial immunodiffusion (RID) or ELISA, multiple studies attempted to develop indirect methods, which would be affordable and operational in the field. These aim to draw an inference for the absorbed quantity of colostral antibodies based on other correlated parameters. Multiple validations showed in part significant differences between various methods concerning specificity and sensitivity in comparison to the direct methods. In addition to RID and ELISA, this article presents the measurement of the γ-glutamyltransferase (GGT) activity, the determination of the total serum protein concentration using refractometry and the zinc sulphate turbidity test, and describes the advantages and disadvantages of their application. Refractory measurement and determination of the GGT activity represent a valuable alternative to a laboratory-dependent immunoglobulin G measurement. Nevertheless, there is no ideal rapid test method, such that several influencing factors have to be considered.


Assuntos
Animais Recém-Nascidos/imunologia , Bovinos/imunologia , Imunoglobulina G/sangue , Animais , Animais Recém-Nascidos/sangue , Proteínas Sanguíneas/análise , Bovinos/sangue , Colostro/imunologia , Ensaio de Imunoadsorção Enzimática/economia , Ensaio de Imunoadsorção Enzimática/métodos , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Imunodifusão/economia , Imunodifusão/métodos , Imunodifusão/veterinária , Nefelometria e Turbidimetria/veterinária , Refratometria/veterinária , Sensibilidade e Especificidade , gama-Glutamiltransferase/sangue
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