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1.
Vet Res ; 51(1): 110, 2020 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-32883344

RESUMO

Canine parvovirus (CPV) can cause acute and highly contagious bloody enteritis in dog. To obtain antibodies against CPV, hens were immunized with virus-like particles (VLP) of CPV-VP2. The IgY single chain fragment variables (scFv) were generated by T7 phage display system and expressed in E. coli system. The titer of the primary scFv library reached to 1.5 × 106 pfu/mL, and 95% of the phages contained the target fragments. The CPV-VLP and CPV-VP2 protein showed similar reaction values to the purified scFv in the ELISA test, and the results of ELISA analysis using IgY-scFv toward CPV clinical samples were consistent with commercial immunochromatographic assay (ICA) and PCR detection, the scFv did not show cross reactivity with canine distemper virus (CDV) and canine coronavirus (CCV). IgY-scFv was successfully expressed in CRFK cells, and in the virus suppression assay, 55% of CPV infections were eliminated within 24 h. Docking results demonstrated that the number of amino acids of the binding sides between scFv and VP2 were AA37 and AA40, respectively. This study revealed the feasibility of a novel functional antibody fragment development strategy by generating diversified avian IgY-scFv libraries towards the pathogenic target of interest for both detection and therapeutic purposes in veterinary medicine.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Proteínas do Capsídeo/imunologia , Doenças do Cão/virologia , Imunoglobulinas/imunologia , Infecções por Parvoviridae/veterinária , Parvovirus Canino/imunologia , Anticorpos de Cadeia Única/imunologia , Animais , Galinhas/imunologia , Doenças do Cão/diagnóstico , Doenças do Cão/imunologia , Cães , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Simulação de Acoplamento Molecular , Infecções por Parvoviridae/diagnóstico , Infecções por Parvoviridae/imunologia , Infecções por Parvoviridae/virologia , Anticorpos de Cadeia Única/genética
2.
PLoS One ; 15(6): e0233695, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32479551

RESUMO

Johne's disease (JD) is an infectious wasting condition of ruminants caused by Mycobacterium avium subsp. paratuberculosis (MAP) in domestic livestock of every country that has been investigated. Controlling JD is problematic due to the lack of sensitive, specific, efficient, and cost-effective diagnostic tests. A major challenge in the development of diagnostics like ELISA is the selection of an ideal antigen/(s) that is pathogen-specific and allows sensitive recognition. Therefore, the purpose of this study was to identify and use Mce-truncated protein-based ELISA assay for the diagnosis of MAP infection with high sensitivity and specificity. In silico epitope prediction by epitope mapping throughout the whole length of MAP2191 protein revealed that C-terminal portion of this protein presented potential T- and B-cell epitopes. Therefore, a novel Mce-truncated protein encoded by the selected region of MAP2191 gene was expressed, purified with Ni-NTA gel matrix and confirmed by SDS PAGE and western blot. A profiling ELISA assay was developed to evaluate sera from MAP infected and non-infected ruminant species for antibodies against Mce-truncated protein to infer the immunogenicity of this protein in the host. Using this Mce protein-based ELISA, 251 goats, 53 sheep, 117 buffaloes, and 33 cattle serum samples were screened and 49.4, 51.0, 69.2, and 54.6% animals, respectively, were found positive. Comparing with i-ELISA, the new Mce-based ELISA kit showed a relatively higher specificity but suffered from slightly reduced sensitivity. Mce-based ELISA excluded apparently false positive results of i-ELISA. Mce protein was found to be antigenic and Mce-ELISA test could be employed as a diagnostic test for JD in domestic livestock in view of the a relatively higher specificity and accuracy. The antigenic potential of Mce antigen can also be exploited for the development of a new vaccine for the control of MAP infection.


Assuntos
Doenças dos Bovinos/sangue , Mycobacterium avium/imunologia , Paratuberculose/sangue , Testes Sorológicos/veterinária , Doenças dos Ovinos/sangue , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/imunologia , Bovinos , Doenças dos Bovinos/diagnóstico , Doenças dos Bovinos/microbiologia , Ensaio de Imunoadsorção Enzimática/métodos , Ensaio de Imunoadsorção Enzimática/veterinária , Cabras , Mycobacterium avium/patogenicidade , Paratuberculose/diagnóstico , Paratuberculose/microbiologia , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Testes Sorológicos/métodos , Ovinos , Doenças dos Ovinos/diagnóstico , Doenças dos Ovinos/microbiologia
3.
Trop Anim Health Prod ; 52(5): 2761-2768, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32488696

RESUMO

Group A rotavirus (RVA) and bovine coronavirus (BCoV) are the two main viral enteropathogens associated with neonatal calf diarrhea. The aim of the present survey was to investigate the epidemiology and the role of RVA and BCoV in the presentation of dairy and beef calf diarrhea in Lerma Valley of Salta province, within the Northwest region of Argentina. Stool samples of calves with or without diarrhea younger than 2 months of age were collected from 19 dairy farms and 20 beef farms between the years 2014 and 2016. Stool samples were screened for RVA and BCoV detection by ELISA. Heminested multiplex RT-PCR was used for RVA typing and RT-PCR to confirm BCoV. Positive samples were submitted to sequencing analysis. Bovine RVA and BCoV were circulating in 63% (12/19) and 10.52% (2/19) of the dairy farms, respectively, where 9.5% (46/484) of the calves were positives to RVA and 0.4% (2/484) to BCoV. In beef herds, RVA was detected in 40% (8/20) of the farms and in 6.75% (21/311) of the calves, without positives cases of BCoV. Molecular analysis showed that in dairy farms, G6P[11] and G10P[11] were the prevalent RVA strains, while in beef farms, G10P[11] was the prevalent. The main finding was the detection for the first time of a G15P[11] causing diarrhea in beef calves of Argentina that represents a new alert to be consider for future vaccine updates. Analysis of detected BCoV showed that it is related to the other circulating strains of Argentina.


Assuntos
Doenças dos Bovinos/virologia , Coronavirus Bovino/isolamento & purificação , Diarreia/veterinária , Infecções por Rotavirus/veterinária , Rotavirus/isolamento & purificação , Animais , Animais Recém-Nascidos , Argentina , Bovinos , Coronavirus Bovino/genética , Diarreia/virologia , Ensaio de Imunoadsorção Enzimática/veterinária , Fezes/virologia , Genótipo , Rotavirus/genética , Infecções por Rotavirus/virologia
4.
Rev Bras Parasitol Vet ; 29(2): e001120, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32490894

RESUMO

This study aimed to determine the seroprevalence, factors associated with seropositivity to Leishmania infection in dogs and spatial analysis in six municipalities in the semiarid region of Pernambuco, Brazil. Blood samples were collected from 462 dogs, 77 in each municipality, and used for serological analysis [dual path platform (DPP®) and enzyme-linked immunosorbent assay (ELISA)]. Clinical signs of dogs were evaluated and associated factors for Leishmania infection were analyzed using robust Poisson regression model. A seroprevalence of 42.8% (198/462, IC: 95% = 38.6%-47.6%) was detected in dogs that tested positive in both tests, ranging from 29.8% to 55.8%, with higher prevalence in the municipality of Cabrobó (55.8%; P = 0.006). About 67% (132/198) of the seropositive dogs showed one or more clinical signs suggestive of canine leishmaniasis (CanL), such as lymphadenomegaly, skin lesions and conjunctivitis, which were associated with seropositivity. High seroprevalence levels were identified in urban and rural areas in all the municipalities, and the buffer for sand flies around cases covered almost these entire areas. Spatial analysis revealed a significant cluster, showing a relative risk of 1.88 in the urban area of Cabrobó. The higher density of seropositive dogs in urban areas indicates the need effective control measures against CanL to prevent the emergence of canine and human diseases.


Assuntos
Anticorpos Antiprotozoários/sangue , Doenças do Cão/epidemiologia , Leishmania infantum/imunologia , Leishmaniose Visceral/veterinária , Animais , Brasil/epidemiologia , Doenças do Cão/diagnóstico , Cães , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Leishmaniose Visceral/diagnóstico , Leishmaniose Visceral/epidemiologia , Masculino , Prevalência , Fatores de Risco , Estudos Soroepidemiológicos , Análise Espacial
5.
Rev Bras Parasitol Vet ; 29(2): e003520, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32520088

RESUMO

Blood samples and swabs from ocular conjunctiva and mouth were obtained from 64 cats. Of 64 serum samples, 19 were positive for Leishmania antibodies by ELISA (29.80%). Eight cats were positive by PCR (12.5%) in swab samples from mouth and/or ocular mucosa. Poor kappa agreement between serological and molecular results (k = 0.16) was obtained. From five positive PCR samples one was L. braziliensis and four were L. infantum. Phylogenetic analysis performed with the five isolates of Leishmania, showed that samples of L. infantum isolated from the cats were phylogenetically close to those isolated from domestic dogs in Brazil, while the L. braziliensis is very similar to the one described in humans in Venezuela. The study demonstrated that, despite high seropositivity for Leishmania in cats living in the study region, poor agreement between serological and molecular results indicate that positive serology is not indicative of Leishmania infection in cats. Parasite DNA can be detected in ocular conjunctiva and oral swabs from cats, indicating that such samples could be used for diagnosis. Results of phylogenetic analyzes show that L. infantum circulating in Brazil is capable of infecting different hosts, demonstrating the parasite's ability to overcome the interspecies barrier.


Assuntos
Doenças do Gato/parasitologia , Leishmania braziliensis/isolamento & purificação , Leishmania infantum/isolamento & purificação , Leishmaniose/parasitologia , Animais , Anticorpos Antiprotozoários/sangue , Doenças do Gato/diagnóstico , Gatos , DNA de Protozoário/análise , Ensaio de Imunoadsorção Enzimática/veterinária , Leishmania braziliensis/genética , Leishmania braziliensis/imunologia , Leishmania infantum/genética , Leishmania infantum/imunologia , Leishmaniose/diagnóstico , Filogenia , Reação em Cadeia da Polimerase/veterinária
6.
Rev Soc Bras Med Trop ; 53: e20190525, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32428174

RESUMO

INTRODUCTION: Canine visceral leishmaniasis (CVL) is a public health problem, and its prevalence is associated with the coexistence of vectors and reservoirs. CVL is a protozoonosis caused by Leishmania infantum that is endemic in the southeast region of Brazil. Thus, vector and canine reservoir control strategies are needed to reduce its burden. This study aimed to verify the CVL seroprevalence and epidemiology in a municipality in Southeast Brazil to initiate disease control strategies. METHODS: A total of 833 dogs were subjected to Dual Path Platform (DPP) testing and enzyme-linked immunosorbent assays. For seropositive dogs, epidemiological aspects were investigated using a questionnaire and a global position system. The data were submitted to simple logistic regression, kernel estimation, and Bernoulli spatial scan statistical analysis. RESULTS: The overall CVL-confirmed seroprevalence was 16.08%. The 28.93% in the DPP screening test was associated with dogs maintained in backyards with trees, shade, animal and/or bird feces, and contact with other dogs and cats, with sick dogs showing the highest chances of infection (odds ratio, 2.6; 95% confidence interval, 2.38-1.98), especially in residences with elderly people. A spatial analysis identified two hotspot regions and detected two clusters in the study area. CONCLUSIONS: Our results demonstrated that residences with elderly people and the presence of trees, shade, feces, and pet dogs and cats increased an individual's risk of developing CVL. The major regions where preventive strategies for leishmaniasis were to be initiated in the endemic area were identified in two clusters.


Assuntos
Doenças do Cão/epidemiologia , Leishmaniose Visceral/veterinária , Animais , Anticorpos Antiprotozoários/sangue , Brasil/epidemiologia , Gatos , Doenças do Cão/diagnóstico , Cães , Doenças Endêmicas , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Leishmania infantum/imunologia , Leishmaniose Visceral/diagnóstico , Leishmaniose Visceral/epidemiologia , Masculino , Prevalência , Estudos Soroepidemiológicos , Análise Espacial
7.
Medicina (B Aires) ; 80(2): 103-110, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32282314

RESUMO

To diagnose dogs infected by Leishmania infantum rK39 rapid diagnosis test is widely used in the Americas, while dual path platform (DPP) was recently adopted by Brazil. In this study we assessed the performance of rK39-RDT and DPP tests in recent urban transmission scenarios of Argentina. The sensitivity and specificity were evaluated with a sera panel and field samples, taken as true infected those from parasitological and/or PCR positive tests. Since none of these tests can be taken as a gold standard, the performance was also evaluated using Latent Class Analysis, a statistical modeling technique which allows to estimating sensitivity and specificity defining a latent class variable as the reference standard. The sensitivity of both tests in the panel was around 92% (symptomatic dogs 96%, asymptomatic 83%), while the sensitivity in field samples of rK39-RDT was 77%, and DPP 98% (mean in symptomatic dogs 89%, asymptomatic 82%). The specificity was similar for both tests and samples, around 98%. Therefore, these tests are acceptable for program dog population-based studies, as spatial stratification, focus intervention and follow up, and they could be used for individual screening and confirmation of clinical presumptive diagnosis in polysymptomatic dogs. The inability to discriminate between immunity and actual infectiousness suggest that a combination with other non-immunological based tests will be required for highly sensitive/specific diagnosis in order to targeting control measures in individual reservoirs from public health perspective, as for individual management from animal health perspective.


Assuntos
Doenças do Cão/diagnóstico , Leishmaniose Visceral/veterinária , Animais , Argentina , Brasil , Doenças do Cão/transmissão , Cães , Ensaio de Imunoadsorção Enzimática/veterinária , Leishmaniose Visceral/diagnóstico , Leishmaniose Visceral/transmissão , Reação em Cadeia da Polimerase/veterinária , Sensibilidade e Especificidade
8.
Vet Parasitol ; 281: 109101, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32302944

RESUMO

Neosporosis is caused by infection with the protozoa Neospora caninum. It manifests as various neurological symptoms and is considered as one of the main causes of abortion in cattle, and induces uncommon congenital infection in sheep. The standard diagnosis is based on indirect immunofluorescence (IFI); however, cross-reactivity with other protozoa proteins is common. Aiming a more specific diagnosis, recombinant antigens have been tested in several immunoassays; of these, NcSAG1 (surface antigen-1) and NcSRS2 (SAG1-related sequence 2) were the most promising. In this context, we developed an indirect ELISA with recombinant NcSRS2 (ELISA-rNcSRS2) and NcSAG1 (ELISA-rNcSAG1) proteins alone and in association (ELISA-rNcSRS2/rNcSAG1) for the diagnosis of cattle and ovine neosporosis. A total of 216 samples from cattle and 154 samples from sheep were used to evaluate the ELISAs. The sensitivity and specificity results of the ELISA-rNcSRS2 were 91.5 % and 96.4 % for cattle, and 89.6 % and 96.3 % for sheep, respectively. For the ELISA-rNcSAG1, the sensitivity and specificity were 84.9 % and 97.3 % for cattle, and 89.6 % and 92.6 % for sheep, respectively. The sensitivity and specificity of the ELISA-rNcSRS2/rNcSAG1 was 98.1 % and 99.1 % for cattle, 100 % and 97.2 % for sheep, respectively. These results indicated that indirect ELISA using the rNcSRS2 and rNcSAG1 proteins are a highly sensitive and specific method, especially when used in association, for detecting antibodies in cattle and ovine populations infected with N. caninum.


Assuntos
Coccidiose/veterinária , Ensaio de Imunoadsorção Enzimática/veterinária , Neospora/imunologia , Animais , Bovinos , Doenças dos Bovinos/diagnóstico , Coccidiose/diagnóstico , Técnica Indireta de Fluorescência para Anticorpo , Neospora/genética , Proteínas de Protozoários/imunologia , Proteínas Recombinantes/imunologia , Sensibilidade e Especificidade , Ovinos , Doenças dos Ovinos/diagnóstico
9.
Transbound Emerg Dis ; 67(4): 1745-1749, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32303108

RESUMO

The pandemic SARS-CoV-2 has been reported in 123 countries with more than 5,000 patients died from it. However, the original and intermediate hosts of the virus remain unknown. In this study, 1,914 serum samples from 35 animal species were used for detection of SARS-CoV-2-specific antibodies using double-antigen sandwich ELISA after validating its specificity and sensitivity. The results showed that no SARS-CoV-2-specific antibodies were detected in above samples which excluded the possibility of 35 animal species as intermediate host for SARS-CoV-2. More importantly, companion animals including pet dogs (including one dog the SARS-CoV-2 patient kept and two dogs which had close contact with it) and cats, street dogs and cats also showed serological negative to SARS-CoV-2, which relieved the public concerns for the pets as SARS-CoV-2 carriers.


Assuntos
Técnicas de Laboratório Clínico/veterinária , Infecções por Coronavirus/epidemiologia , Pandemias , Pneumonia Viral/epidemiologia , Animais , Animais Selvagens , Anticorpos Antivirais/sangue , Betacoronavirus/imunologia , Gatos , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/veterinária , Cães , Ensaio de Imunoadsorção Enzimática/veterinária , Animais de Estimação
10.
Rev Bras Parasitol Vet ; 29(1): e019119, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32236334

RESUMO

Serological screening of 199 serum samples from Dromedary camels-from different cities in Saudi Arabia-was performed using enzyme-linked immunosorbent assay for detecting antibodies against two cyst-forming coccidian parasites, namely Toxoplasma gondii and Neospora caninum. Antibodies against T. gondii were detected in 68 (34.2%) samples, while those against N. caninum were present in 33 (16.6%) samples. The highest seroprevalence of T. gondii antibodies was reported in samples from Taif (51.2%), while the lowest seroprevalence was reported in samples from Riyadh and Hofuf (15.1%). The highest seroprevalence of N. caninum antibodies was reported in samples from Jizan (35.9%) while the lowest was reported in samples from Taif (2.4%). A total of 47 male and 21 female camels exhibited antibodies against T. gondii , while 19 male and 14 female camels showed antibodies against N. caninum . Concurrent detection of both T. gondii and N. caninum antibodies was observed in 18 camels. It has been demonstrated that T. gondii and N. caninum antibodies are prevalent in camels from different cities of the Kingdom of Saudi Arabia.


Assuntos
Anticorpos Antiprotozoários/sangue , Camelus/parasitologia , Coccidiose/veterinária , Neospora/imunologia , Toxoplasma/imunologia , Toxoplasmose Animal/epidemiologia , Animais , Coccidiose/epidemiologia , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Masculino , Arábia Saudita/epidemiologia , Estudos Soroepidemiológicos , Toxoplasmose Animal/diagnóstico
11.
Mem Inst Oswaldo Cruz ; 115: e190349, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32348406

RESUMO

BACKGROUND: Visceral leishmaniasis (VL) is relevant for human and animal public health. Several factors have been associated with the risk of Leishmania infantum infection in dogs. However, dog owner characteristics have been rarely explored. OBJECTIVES: To estimate the prevalence and to identify the associated factors for VL infection including dog owners characteristics. METHODS: A cross-sectional study was conducted including dogs from an endemic canine visceral leishmaniasis (CVL) region in the Federal District, Brazil. The infection was detected using parasitological, serological, and molecular methods. The associated factors were identified through Poisson regression modelling. FINDINGS: The prevalence of infection was 26.25% [95% confidence interval (CI): 20.05 to 33.57]. The associated factors were: short coat prevalence ratio (PR) = 2.33 (95% CI: 1.02 to 5.22); presence of backyard with predominance of soil and/or vegetation PR = 4.15 (95% CI: 1.35 to 12.77); and highest gross family income score PR = 2.03 (95% CI: 1.16 to 3.54). MAIN CONCLUSION: This is the first study that relates higher socioeconomic status of dog owners as an independent factor associated with higher prevalence of VL infection, along with other strongly associated factors related to receptive environment for phlebotomines. Our findings strengthen the need for exploration of the biological and behavioural bases linking dog owner characteristics to the risk of canine infection in prospective cohort studies.


Assuntos
Doenças do Cão/epidemiologia , Leishmaniose Visceral/veterinária , Animais , Brasil/epidemiologia , Estudos Transversais , Doenças do Cão/diagnóstico , Cães , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Humanos , Leishmaniose Visceral/diagnóstico , Leishmaniose Visceral/epidemiologia , Masculino , Prevalência , Estudos Prospectivos , Fatores de Risco , Fatores Socioeconômicos
12.
PLoS Negl Trop Dis ; 14(4): e0008222, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32330132

RESUMO

BACKGROUND: Leptospirosis is a zoonotic disease that can be transmitted by contact with the urine of infected mammals. Rodents play a mayor role in the transmission of leptospires to humans. The province of Santa Fe reports the greatest number of cases in Argentina. Yet, in this region, there are still knowledge gaps regarding the diversity of rodent species that may be hosts of pathogenic leptospires. The aims of this study were to evaluate the presence of leptospiral antibodies in rodents from three riverside communities of Santa Fe, and to identify factors associated with leptospiral infection. METHODOLOGY/PRINCIPAL FINDINGS: Each community was divided into three environmental settings based on the level of human disturbance, and sampled during two springs (Sep-Oct 2014 and 2015) and one autumn (Mar-Apr 2015). Serum samples of captured sigmodontine and murine rodents were tested for leptospiral antibodies by enzyme-linked immunosorbent assay (ELISA), and microagglutination test (MAT) was used to assess the infecting serovar in seropositive individuals. Factors influencing seropositivity were analyzed using logistic regression models. We caught 119 rodents, of which 101 serums were suitable for analysis. Most frequently trapped species were Scapteromys aquaticus, Akodon azarae and Oligoryzomys spp., with seroprevalences of 41.3%, 42.9% and 55% respectively. Seropositivity was higher in individuals with an average body condition score and in those that were sexually mature, but in the latter the differences were marginally significant. CONCLUSIONS/SIGNIFICANCE: Our results suggest that native rodents may be playing a role in the environmental circulation of pathogenic leptospires and provide relevant information for public health policies in the area.


Assuntos
Anticorpos Antibacterianos/sangue , Leptospirose/veterinária , Doenças dos Roedores/epidemiologia , Roedores/microbiologia , Animais , Argentina/epidemiologia , Monitoramento Ambiental , Ensaio de Imunoadsorção Enzimática/veterinária , Monitoramento Epidemiológico , Feminino , Rim/microbiologia , Leptospira/isolamento & purificação , Leptospirose/epidemiologia , Masculino , Ratos , Doenças dos Roedores/sangue , Doenças dos Roedores/microbiologia , Roedores/classificação , Estudos Soroepidemiológicos
13.
Can Vet J ; 61(4): 420-423, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32255830

RESUMO

A commercial porcine reproductive and respiratory syndrome virus (PRRSV) oral fluid antibody enzyme-linked immunosorbent assay (ELISA) was used on 31 commercial swine farms in Ontario using oral fluid samples (~6 per herd) collected from cotton ropes. Using the manufacturer's cutoff [sample-to-positive ratio (S/P) ≥ 0.4], 2 of 135 oral fluid samples from 23 PRRSV presumed negative herds tested positive (1.5% false positive rate). Three approaches to improving test diagnostic specificity were compared: i) use a cutoff of S/P ≥ 0.8 for individual oral fluid samples; ii) use the current cutoff of S/P ≥ 0.4 but use a mean S/P based on several oral fluid samples (6 samples were used in this study); and iii) use serial testing to resolve unexpected positive ELISA results, i.e., retest using a reverse transcription-polymerase chain reaction (RT-PCR) to determine whether low positive S/P ratios are the result of early PRRSV infection in a barn.


Assuntos
Síndrome Respiratória e Reprodutiva Suína , Vírus da Síndrome Respiratória e Reprodutiva Suína , Doenças dos Suínos , Animais , Anticorpos Antivirais , Ensaio de Imunoadsorção Enzimática/veterinária , Ontário , Saliva , Suínos
14.
J Vet Diagn Invest ; 32(3): 401-408, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32306865

RESUMO

Neospora caninum is a protozoan parasite that causes abortion and important economic losses in cattle worldwide. There are no treatments or vaccines available; disease control is based on diagnosis and herd management strategies. We developed, validated, and evaluated under field conditions a competitive inhibition ELISA based on the truncated SAG1 protein (tSAG1), expressed in Escherichia coli, and the RafNeo5 monoclonal antibody (ciELISAtSAG1). A criterion based on the 3-y sequential serologic analysis of 230 dairy cows by IFAT was used as the gold standard. The assay was validated using 860 serum samples from cows that were consistently positive or negative by IFAT throughout the study period. ciELISAtSAG1 was then used to evaluate the prevalence of neosporosis in 16 beef cow herds (22 samples per herd, 352 total samples). The results were compared with those from IFAT and a commercial cELISA (cELISAVMRD). The ciELISAtSAG1 cutoff was ≥ 29%I, with a diagnostic sensitivity of 98.7% (95% CI = 96.8-99.7%) and a diagnostic specificity of 97.9% (95% CI = 96.4-99.0%). Concordance among IFAT, cELISAVMRD, and ciELISAtSAG1 was 90.3%. The agreement (κ) between ciELISAtSAG1 and the other 2 tests was ≥ 0.81. The overall prevalence of neosporosis in the 16 beef herds was 30% (range: 5-60%). The ciELISAtSAG1 could be useful for large-scale detection of anti-N. caninum antibodies in cattle and seroepidemiologic investigations, given its appropriate sensitivity and specificity, and the simplicity of production.


Assuntos
Anticorpos Antiprotozoários/sangue , Doenças dos Bovinos/diagnóstico , Coccidiose/veterinária , Ensaio de Imunoadsorção Enzimática/veterinária , Neospora/isolamento & purificação , Proteínas de Protozoários/análise , Proteínas Recombinantes/análise , Animais , Bovinos , Doenças dos Bovinos/parasitologia , Coccidiose/diagnóstico , Coccidiose/parasitologia , Ensaio de Imunoadsorção Enzimática/métodos
15.
J Vet Diagn Invest ; 32(3): 444-449, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32270752

RESUMO

An outbreak of inclusion body hepatitis caused by fowl adenovirus serotype 8 (FAdV-8) has caused significant economic losses in the poultry industry worldwide. However, a rapid serology test kit specific to FAdV-8 is not available to date. We developed a fiber-based ELISA using the purified GST-fiber of FAdV-8 as coating antigen to measure antibodies against FAdV-8. Specificity analysis showed that our ELISA could react with sera against FAdV-7, -8a, and -8b, but not with sera against the other pathogens tested. Moreover, detection of positive sera with our ELISA had 83% and 94% agreement with an indirect immunofluorescence assay (IFA) and a commercial ELISA from BioChek, respectively. Our ELISA was also effective in the detection of antibodies against FAdV-8 in sera from both experimentally infected and clinically vaccinated chickens. Our FAdV-8 fiber-based ELISA can be a valuable tool to specifically and sensitively detect antibodies against FAdV-7 and/or -8 in infected or vaccinated chickens.


Assuntos
Anticorpos Antivirais/sangue , Aviadenovirus/imunologia , Galinhas/virologia , Ensaio de Imunoadsorção Enzimática/veterinária , Doenças das Aves Domésticas/virologia , Infecções por Adenoviridae/veterinária , Animais , Aviadenovirus/classificação , Doenças das Aves Domésticas/diagnóstico , Sensibilidade e Especificidade , Sorogrupo , Testes Sorológicos/veterinária
16.
Transbound Emerg Dis ; 67 Suppl 1: 40-55, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32174040

RESUMO

Leucoproliferative Theileria parasites possess the unique capability to transform their bovine host cell, resulting in tumour-like characteristics like uncontrolled proliferation. The molecular mechanisms underlying this parasite-dependent process are only poorly understood. In the current study, bioinformatic analysis of the Theileria annulata surface protein (TaSP) from different T. annulata isolates identified a conserved CDK1 phosphorylation motif T131 PTK within the extracellular, polymorphic domain of TaSP. Phosphorylation assays with radioactively labelled ATP as well as ELISA-based experiments using a phospho-threonine-proline (pThr-Pro) antibody revealed, that CDK1-cyclin B specifically phosphorylates T131 , identifying TaSP as a substrate in vitro. Confocal microscopy and proximity ligation assays suggest an interaction between CDK1 and TaSP in T. annulata-infected cells. Further studies demonstrated a nearly complete co-localization of the pThr-Pro signal and TaSP only in cells in interphase, pointing towards a cell cycle-dependent event. Immunostainings of isolated, non-permeabilized schizonts confirmed the presence of the pThr-Pro epitope on the schizont's surface. Lambda phosphatase treatment abolished the pThr-Pro signal of the schizont, which was reconstituted by the addition of CDK1-cyclin B. Treatment of T. annulata-infected cells with the CDK1 inhibitor purvalanol A resulted in morphological changes characterized by tubulin-rich cell protrusions and an extension of the schizont, and a dose-dependent reduction of BrdU incorporation and Ki67 staining of T. annulata-infected cells, demonstrating a clear impact on the Theileria-dependent proliferation of the bovine host cell. Our data reveal the parasite surface protein TaSP as a target for the host cell kinase CDK1, a major player during cell division. Targeting the uncontrolled proliferation of Theileria-infected cells is a novel and reasonable approach to limit parasite load in order to facilitate a successful cellular immune response against the parasite.


Assuntos
Proteína Quinase CDC2/metabolismo , Doenças dos Bovinos/prevenção & controle , Proteínas de Protozoários/metabolismo , Theileria annulata/imunologia , Theileriose/prevenção & controle , Motivos de Aminoácidos , Animais , Proteína Quinase CDC2/antagonistas & inibidores , Bovinos , Doenças dos Bovinos/parasitologia , Proliferação de Células , Ensaio de Imunoadsorção Enzimática/veterinária , Fosforilação , Purinas/farmacologia , Esquizontes , Theileria annulata/metabolismo , Theileriose/parasitologia
17.
J Vet Diagn Invest ; 32(3): 481-485, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32194000

RESUMO

We characterized the antibody response to decorin-binding protein A (DbpA) or DbpB from immune serum samples collected from 27 dogs infected with Borrelia burgdorferi by Ixodes scapularis ticks. Immunoglobulin M (IgM) antibodies to DbpA or DbpB were rarely detected, but high levels of IgG antibodies to DbpA were detected in 16 of 27 of the immune sera collected 1 mo after infection, 20 of 25 of the sera collected after 2 mo, and each of the 23, 17, or 11 serum samples evaluated after 3, 4, or 5 mo, respectively. In addition, IgG antibodies to DbpB were detected in 22 of 27 (p = 0.005) tested dogs after 1 mo, and the frequency of detecting the antibodies thereafter closely mimicked the antibody responses to DbpA. Moreover, antibodies to DbpA or DbpB were not produced by dogs vaccinated with a whole-cell B. burgdorferi bacterin; removing the antibodies to DbpA by adsorption to recombinant DbpA (rDbpA) did not affect the reactivity detected by a rDbpB ELISA. Therefore, the findings from our preliminary study showed that antigenically distinct antibodies to DbpA or DbpB are produced reliably during canine infection with B. burgdorferi, and the response is not confounded by vaccination with a Lyme disease bacterin. Larger studies are warranted to more critically evaluate whether detecting the antibody responses can improve serodiagnostic confirmation of canine Lyme disease.


Assuntos
Anticorpos Antibacterianos/sangue , Borrelia burgdorferi/imunologia , Doenças do Cão/microbiologia , Doença de Lyme/veterinária , Adesinas Bacterianas/metabolismo , Animais , Anticorpos Antibacterianos/imunologia , Proteínas da Membrana Bacteriana Externa/imunologia , Doenças do Cão/transmissão , Cães , Ensaio de Imunoadsorção Enzimática/veterinária , Doença de Lyme/imunologia , Doença de Lyme/microbiologia , Carrapatos/imunologia , Carrapatos/metabolismo
18.
Acta Trop ; 205: 105435, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32142734

RESUMO

An extended range of host susceptibility including camel has been evidenced for some of the important veterinary and public health pathogens, such as brucellosis, peste des petits ruminants (PPR) and bluetongue (BT). However, in disease endemic settings across many parts of the globe, most of the disease control interventions accounts for small and large ruminants, whereas unusual hosts and/or natural reservoirs, such as camels, remain neglected for disease control measures including routine vaccination. Such a policy drawback not only plays an important role in disease epizootiology particularly in settings where disease is endemic, but also serves an obstacle in disease control and subsequent eradication in future. With this background, using pre-validated ELISA and molecular assays [multiplex PCR, reverse transcriptase (RT)-PCR and real-time (rt)-PCR], we conducted a large-scale pathogen- and antibody-based surveillance for brucellosis, peste des petits ruminants and bluetongue in camel population (n = 992) originating from a wide geographical region in southern part of the Punjab province, Pakistan. Varying in each of the selected districts, the seroprevalence was found to be maximum for bluetongue [n = 697 (70.26%, 95% CI: 67.29-73.07)], followed by PPR [n = 193 (19.46%, 95% CI: 17.07-22.09)] and brucellosis [n = 66 (6.65%, 95% CI: 5.22-8.43)]. Odds of seroprevalence were more significantly associated with pregnancy status (non-pregnant, OR = 2.23, 95% CI: 1.86-5.63, p<0.01), farming system (mixed-animal, OR = 2.59, 95% CI: 1.56-4.29, p<0.01), breed (Desi, OR = 1.97, 95% CI: 1.28-4.03, p<0.01) and farmer education (illiterate, OR = 3.17, 95% CI: 1.45-6.93, p<0.01) for BTV, body condition (normal, OR = 3.54, 95% CI: 1.92-6.54, p<0.01) and breed (Desi, OR = 2.19, 95% CI: 1.09-4.40, p<0.01) for brucellosis, and feeding system for PPR (grazing, OR = 2.75, 95% CI: 1.79-4.22, p<0.01). Among the total herds included (n = 74), genome corresponding to BT virus (BTV) and brucellosis was detected in 14 (18.92%, 95 CI: 11.09-30.04) and 19 herds (25.68%, 95% CI: 16.54-37.38), respectively. None of the herds was detected with genome of PPR virus (PPRV). Among the positive herds, serotype 1, 8 and 11 were detected for BTV while all the herds were exclusively positive to B. abortus. Taken together, the study highlights the role of potential disease reservoirs in the persistence and transmission of selected diseases in their susceptible hosts and, therefore, urges necessary interventions (e.g., inclusion of camels for vaccine etc.) for the control of diseases from their endemic setting worldwide.


Assuntos
Bluetongue/epidemiologia , Brucelose/veterinária , Camelus/microbiologia , Peste dos Pequenos Ruminantes/epidemiologia , Animais , Brucelose/epidemiologia , Brucelose/microbiologia , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Paquistão/epidemiologia , Gravidez , Saúde Pública , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Risco , Estudos Soroepidemiológicos , Sorogrupo
19.
Parasitol Res ; 119(3): 1001-1009, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32056024

RESUMO

A retrospective study based on cases of canine dirofilariosis presented to the University of Veterinary Medicine, Vienna or diagnosed by private practitioners throughout Austria, from 1998 to 2018 was conducted to investigate the long-term development and current state of canine dirofilarial infections in Austria. Included in this study were 146 dogs which were tested positive for D. immitis and/or D. repens. The most commonly used diagnostic methods and the probable geographical origins of the infections were evaluated and the treatment protocols applied were compared with each other and with the literature. The results show that most infections were found due to screening for common travel infections using antigen-ELISA or PCR-testing, or by the incidental finding of microfilariae. Remarkably, only 24.3% of all cases presented showed clinical signs indicating canine dirofilariosis. Regarding the origin and travel history of the dogs, thirteen different countries could be identified. The three treatment protocols used showed a similar outcome after 8 months of treatment and minor side effects, which is consistent with the literature. An alarming increase in reported infections with both D. immitis and D. repens in Austria was noted since 2014. The number of documented cases had almost tripled by 2018, raising severe concerns about the threat of it becoming endemic in Austria. Therefore, the existing recommendations in current guidelines regarding canine dirofilariosis should be widely publicised and more strictly enforced. Prophylactic measures for dogs travelling abroad and diagnostic and therapeutic strategies for dogs imported from endemic countries should be obligatorily established throughout Europe, to reduce the risk of further spread of canine filarial infections to non-endemic regions.


Assuntos
Dirofilariose/diagnóstico , Dirofilariose/epidemiologia , Doenças do Cão/diagnóstico , Doenças do Cão/epidemiologia , Microfilárias/isolamento & purificação , Animais , Áustria/epidemiologia , Dirofilariose/tratamento farmacológico , Dirofilariose/transmissão , Doenças do Cão/tratamento farmacológico , Doenças do Cão/transmissão , Cães , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Masculino , Microfilárias/classificação , Microfilárias/genética , Microfilárias/imunologia , Reação em Cadeia da Polimerase/veterinária , Estudos Retrospectivos , Viagem
20.
Parasitol Res ; 119(4): 1381-1386, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32107620

RESUMO

The prevalence data of Leishmania infantum infection in cats are characterized by a large variability mainly attributed to the differences in diagnostic techniques. In the absence of consensus about the method of choice for diagnosing feline leishmaniosis, the performance of a new immunofluorescence antibody test (IFAT) was herein analytically described by the comparison with IFAT commonly used for the diagnosis of canine leishmaniosis (i.e., IFAT-OIE) and a laboratory enzyme-linked immunosorbent assay (ELISA). Sera of cats living in visceral leishmaniosis-endemic (n = 105) and visceral leishmaniosis-non-endemic (n = 50) areas were tested by the above methodologies and real-time PCR (qPCR). The most frequent result was represented by triple negativity to the three tests (IFAT-OIE, ELISA, and qPCR) in 42.9% and 80% cats from endemic and non-endemic areas, respectively. Bayes latent class analysis gave an output probability of 34.1% (posterior standard deviation, psd = 5.4%) of true L. infantum cases (TCL) which represent the true estimated prevalence of infection. The sensitivity of each variable contributing to define the TCL was 24% (psd = 6.3%) for qPCR, 78.8% (psd = 8.7%) for ELISA and 91.8% (psd = 5.2%) for IFAT-OIE. The probability to be a TCL was 94.5% for the sample from an endemic area. The cross-validation of the new IFAT by a logistic model correctly identified as positive 80.7% of subjects defined as TCL and negative 89.9% as not TCL, respectively, by the Bayesian model. The study results estimate a good accuracy of the IFAT in predicting cats exposed to L. infantum. Therefore, this procedure may be beneficial for screening cat populations for a better understanding of the epidemiology of feline leishmaniosis.


Assuntos
Anticorpos Antiprotozoários/sangue , Doenças do Gato/diagnóstico , Técnica Direta de Fluorescência para Anticorpo/métodos , Leishmania infantum/isolamento & purificação , Leishmaniose Visceral/veterinária , Animais , Teorema de Bayes , Doenças do Gato/epidemiologia , Doenças do Gato/parasitologia , Gatos , Ensaio de Imunoadsorção Enzimática/veterinária , Leishmania infantum/genética , Leishmaniose Visceral/diagnóstico , Masculino , Reação em Cadeia da Polimerase em Tempo Real/veterinária
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