Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 8.180
Filtrar
1.
Virulence ; 12(1): 1597-1609, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34125647

RESUMO

The COVID-19 pandemic caused by the coronavirus SARS-CoV-2 is continuing to spread globally. SARS-CoV-2 infections of feline and canine species have also been reported. However, it is not entirely clear to what extent natural SARS-CoV-2 infection of pet dogs and cats is in households. We have developed enzyme-linked immunosorbent assays (ELISAs) using recombinant SARS-CoV-2 nucleocapsid (N) protein and the receptor-binding-domain (RBD) of the spike protein, and the SARS-CoV-2 spike-pseudotyped vesicular stomatitis virus (VSV)-based neutralization assay to screen serum samples of 239 pet cats and 510 pet dogs in Minnesota in the early phase of the COVID-19 pandemic from mid-April to early June 2020 for evidence of SARS-CoV-2 exposures. A cutoff value was used to identify the seropositive samples in each experiment. The average seroprevalence of N- and RBD-specific antibodies in pet cats were 8% and 3%, respectively. Among nineteen (19) N-seropositive cat sera, fifteen (15) exhibited neutralizing activity and seven (7) were also RBD-seropositive. The N-based ELISA is also specific and does not cross react with antigens of common feline coronaviruses. In contrast, SARS-CoV-2 antibodies were detected at a very low percentage in pet dogs (~ 1%) and were limited to IgG antibodies against SARS-CoV-2 N protein with no neutralizing activities. Our results demonstrate that SARS-CoV-2 seropositive rates are higher in pet cats than in pet dogs in MN early in the pandemic and that SARS-CoV-2 N-specific IgG antibodies can detect SARS-CoV-2 infections in companion animals with higher levels of specificity and sensitivity than RBD-specific IgG antibodies in ELISA-based assays.


Assuntos
Teste Sorológico para COVID-19/veterinária , COVID-19/veterinária , Animais de Estimação/virologia , SARS-CoV-2/isolamento & purificação , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , COVID-19/diagnóstico , COVID-19/epidemiologia , Gatos , Proteínas do Nucleocapsídeo de Coronavírus/imunologia , Coronavirus Felino/imunologia , Coronavirus Felino/isolamento & purificação , Cães , Ensaio de Imunoadsorção Enzimática/veterinária , Minnesota/epidemiologia , Fosfoproteínas/imunologia , SARS-CoV-2/imunologia , Sensibilidade e Especificidade , Estudos Soroepidemiológicos , Glicoproteína da Espícula de Coronavírus/imunologia
2.
Virulence ; 12(1): 1597-1609, 2021 12.
Artigo em Inglês | MEDLINE | ID: covidwho-1268053

RESUMO

The COVID-19 pandemic caused by the coronavirus SARS-CoV-2 is continuing to spread globally. SARS-CoV-2 infections of feline and canine species have also been reported. However, it is not entirely clear to what extent natural SARS-CoV-2 infection of pet dogs and cats is in households. We have developed enzyme-linked immunosorbent assays (ELISAs) using recombinant SARS-CoV-2 nucleocapsid (N) protein and the receptor-binding-domain (RBD) of the spike protein, and the SARS-CoV-2 spike-pseudotyped vesicular stomatitis virus (VSV)-based neutralization assay to screen serum samples of 239 pet cats and 510 pet dogs in Minnesota in the early phase of the COVID-19 pandemic from mid-April to early June 2020 for evidence of SARS-CoV-2 exposures. A cutoff value was used to identify the seropositive samples in each experiment. The average seroprevalence of N- and RBD-specific antibodies in pet cats were 8% and 3%, respectively. Among nineteen (19) N-seropositive cat sera, fifteen (15) exhibited neutralizing activity and seven (7) were also RBD-seropositive. The N-based ELISA is also specific and does not cross react with antigens of common feline coronaviruses. In contrast, SARS-CoV-2 antibodies were detected at a very low percentage in pet dogs (~ 1%) and were limited to IgG antibodies against SARS-CoV-2 N protein with no neutralizing activities. Our results demonstrate that SARS-CoV-2 seropositive rates are higher in pet cats than in pet dogs in MN early in the pandemic and that SARS-CoV-2 N-specific IgG antibodies can detect SARS-CoV-2 infections in companion animals with higher levels of specificity and sensitivity than RBD-specific IgG antibodies in ELISA-based assays.


Assuntos
Teste Sorológico para COVID-19/veterinária , COVID-19/veterinária , Animais de Estimação/virologia , SARS-CoV-2/isolamento & purificação , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , COVID-19/diagnóstico , COVID-19/epidemiologia , Gatos , Proteínas do Nucleocapsídeo de Coronavírus/imunologia , Coronavirus Felino/imunologia , Coronavirus Felino/isolamento & purificação , Cães , Ensaio de Imunoadsorção Enzimática/veterinária , Minnesota/epidemiologia , Fosfoproteínas/imunologia , SARS-CoV-2/imunologia , Sensibilidade e Especificidade , Estudos Soroepidemiológicos , Glicoproteína da Espícula de Coronavírus/imunologia
3.
Rev Sci Tech ; 40(1): 53-73, 2021 Jun.
Artigo em Inglês, Francês, Espanhol | MEDLINE | ID: mdl-34140740

RESUMO

Analytical characteristics of diagnostic tests, encompassing estimates of repeatability, analytical specificity (ASp) and analytical sensitivity (ASe), are determined during Stage 1 of the OIE Assay Validation Pathway. Repeatability (an estimate of assay precision and robustness), ASp (measuring only what an assay is intended to measure) and ASe (synonymous with the lower limit of detection) are fundamental parameters that determine future test performance. Importantly, these parameters provide the basis for deciding whether a prototype assay progresses to the next stage of the OIE Assay Validation Pathway (determination of diagnostic characteristics) or is withdrawn in favour of alternate tests with better analytical performance characteristics. Implicit in the successful development and validation of any assay is a sound understanding of the target pathogen, the disease pathogenesis in susceptible hosts, the fundamental technical principles that underliey each test system, and its intended use. Factors that affect analytical characteristics of diagnostic assays are numerous and may vary according to each assay type. Using, as examples, development of an enzyme-linked immunosorbent assay for detection of antibodies to capripoxviruses, and the comparative assessment of three quantitative real-time polymerase chain reactions for detection of African swine fever virus DNA, the main factors affecting analytical characteristics of serological and molecular assays are considered. As reviewed within, comprehensive and well-designed experiments are required to develop and optimise assays with favourable analytical characteristics. The underlying principles are broadly applicable to all assay types and, when conducted with appropriate rigour, provide the foundations for high-quality diagnostic tests that are fit for their intended purpose(s).


Assuntos
Vírus da Febre Suína Africana , Animais , Ensaio de Imunoadsorção Enzimática/veterinária , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Sensibilidade e Especificidade , Suínos
4.
Turkiye Parazitol Derg ; 45(2): 108-112, 2021 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-34103286

RESUMO

Objective: This study aimed to investigate the seroprevalence of Neospora caninum and Besnoitia besnoiti in cattle in the Oguzlar district of Çorum province. Methods: Venous blood samples were collected from the vena jugularis of 100 cattle in the Oguzlar region and stored into anticoagulant-free tubes. Serum samples were examined with commercial c-ELISA kits for N. caninum (IDEXX, Switzerland) and B. besnoiti (ID.vet, France). Results: Two of serum samples were found to be N. caninum (2%) and five were B. besnoiti (5%) seropositive. No mixed infection was detected in any of serum samples. Conclusion: In this study, the presence of N. caninum and B. besnoiti was serologically determined in animals that are not imported in the Oguzlar region. This is the first study in the region to identify B. besnoiti in the seropositive cattle and is the third study in Turkey.


Assuntos
Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/parasitologia , Coccidiose/veterinária , Neospora/isolamento & purificação , Sarcocystidae/isolamento & purificação , Animais , Anticorpos Antiprotozoários/sangue , Bovinos , Coccidiose/epidemiologia , Coccidiose/parasitologia , Ensaio de Imunoadsorção Enzimática/veterinária , Neospora/imunologia , Sarcocystidae/imunologia , Estudos Soroepidemiológicos , Turquia/epidemiologia
5.
Poult Sci ; 100(7): 101190, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34087701

RESUMO

Necrotic enteritis (NE) is a devastating enteric disease caused by Clostridium perfringens type G. One of the pore-forming toxins, NE B-like (NetB) toxin, secreted by pathogenic C. perfringens type G, has been proposed to be the main virulent factor in NE pathogenesis. The present study aimed to detect the presence of NetB toxin in biological samples of NE-afflicted chickens using NetB-specific monoclonal-based enzyme-linked immunosorbent assay (ELISA). Biological samples, including serum, digesta, and fecal droppings, were obtained from three previous NE studies (designated as Trials 1 to 3). In Trials 1 and 2, broiler chicks were infected with Eimeria maxima strain 41A on day 1 and followed by the netB-positive C. perfringens on day 18. Serum samples were obtained at 20 d post-hatch (i.e., 2 d post C. perfringens infection). In addition, various samples, including serum, gut digesta, and fecal droppings, that had been collected 0, 6, 24, and 30 h post C. perfringens infection were obtained. In Trial 3, broiler chicks were indirectly infected with litter-contaminated E. maxima on d 14 and followed by netB-positive C. perfringens via drinking water on days 18, 19, and 20. Serum samples and fecal droppings were obtained 21 d post-hatch (i.e., 1 d post last C. perfringens infection). The results showed that NetB toxin was not detected in serum samples in Trials 1 and 3. No NetB toxin was detected in all samples obtained before C. perfringens infection in Trial 2. Low but detectable amounts of NetB toxin were found in the serum samples obtained 6 h post C. perfringens infection in Trial 2. While NetB toxin in digesta and fecal droppings was detected 6 h post C. perfringens infection, its level plateaued 24 and 30 h post C. perfringens infection. In Trial 3, NetB toxin was detected in fecal droppings from the NE group, and its concentration ranged from 2.9 to 3.1 ng/g of wet feces. In Trial 2, NE-specific lesions were not seen 0 and 6 h post C. perfringens infection but exhibited lesions were moderate to severe 24 h post infection, leading to a moderate association (r = +0.527) between NE lesions and NetB toxin in the gut digesta. This is the first study to use NetB-specific monoclonal-based capture ELISA to determine and report the presence of native NetB toxin in biological samples from NE-induced chickens.


Assuntos
Toxinas Bacterianas , Infecções por Clostridium , Enterite , Doenças das Aves Domésticas , Animais , Galinhas , Infecções por Clostridium/veterinária , Clostridium perfringens , Enterite/veterinária , Enterotoxinas , Ensaio de Imunoadsorção Enzimática/veterinária
6.
J Vet Diagn Invest ; 33(4): 736-739, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34041969

RESUMO

The blacklegged tick (Ixodes scapularis), which transmits Borrelia burgdorferi, the causative agent of Lyme disease, has undergone rapid range expansion in Ontario. In horses, Lyme disease remains an enigmatic disease, with limited understanding of the pathogenesis and many issues pertaining to selection and interpretation of laboratory tests. We evaluated B. burgdorferi seropositivity in naturally exposed horses over a 12-mo period and compared paired samples with 2 common serologic tests. Serum samples were collected in 2017, ~1 y after initial testing, from a cohort of 22 horses that were seropositive in a 2016 seroprevalence study. Samples were tested using a C6 ELISA and a multiplex ELISA targeting outer surface proteins A, C, and F. 1 y after initial testing, 14 of 22 (64%) horses remained seropositive; 7 (32%) were positive on the multiplex ELISA, 2 (9%) on C6 ELISA, and 5 (23%) on both tests. Repeatability was 100% for the C6 ELISA, and 95% for the multiplex ELISA, with no significant difference between paired sample multiplex titer values. Our results indicate strong intra-test reliability, although further investigation is required to determine the clinical significance of serologic testing.


Assuntos
Borrelia burgdorferi/isolamento & purificação , Ensaio de Imunoadsorção Enzimática/veterinária , Doenças dos Cavalos/diagnóstico , Doença de Lyme/veterinária , Testes Sorológicos/veterinária , Animais , Ensaio de Imunoadsorção Enzimática/métodos , Doenças dos Cavalos/sangue , Doenças dos Cavalos/microbiologia , Cavalos , Ixodes/microbiologia , Doença de Lyme/sangue , Doença de Lyme/diagnóstico , Reprodutibilidade dos Testes , Estudos Soroepidemiológicos
7.
Trop Anim Health Prod ; 53(2): 303, 2021 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-33934210

RESUMO

Foot and Mouth Disease (FMD) is a high-impact, contagious transboundary animal disease that is endemic in Southeast Asia. Abattoir samples were routinely collected in six selected provinces between March and December 2019. A total of 1280 samples of abattoir animals were tested for FMD Non-Structural Protein (NSP) antibodies to indicate natural infections. Overall, 22.8% were seropositive for FMD NSP antibodies while seroprevalence of cattle (n = 469), buffalo (n = 214), and pigs (n = 597) were 44.6%, 35.0%, and 1.3%, respectively. The highest seroprevalence destination province was Xiengkhouang (35.3% of 272 samples), followed by Savannakhet (27.0% of 244 samples). Risk factors for evidence of natural infection identified by a multivariate logistic regression model included age groups (p-value = 0.02) and origin provinces (p-value = 2.8 × 10-5) of the animals. There were significant differences of FMD NSP seroprevalence between age groups and origin provinces of the animals. The odds ratio of a seropositive result in the less than 1 year old group was 2.5 (95% CI; 1.4, 4.4) when compared to the 3-4 years old group, while the odds ratios for animals that originated from Khammouane and Xiengkhouang provinces were 4.5 (95% CI; 1.1, 18.7) and 2.4 (95% CI; 1.4, 4.1), respectively, when compared to Champasak province. Serotype-specific antibody ELISA for 44 NSP antibody-positive samples revealed evidence of FMD serotypes O and A virus circulation in some provinces. Despite the passive abattoir survey providing useful information on FMD virus previous exposure and geographic locations of the animals, timely information on FMD virus circulation and distribution is also crucial to an effective control program. Alternative approaches to increase the cost-effectiveness of the surveillance network are also discussed.


Assuntos
Doenças dos Bovinos , Vírus da Febre Aftosa , Febre Aftosa , Doenças dos Suínos , Animais , Anticorpos Antivirais , Bovinos , Doenças dos Bovinos/epidemiologia , Surtos de Doenças , Ensaio de Imunoadsorção Enzimática/veterinária , Febre Aftosa/epidemiologia , Laos/epidemiologia , Estudos Soroepidemiológicos , Suínos , Doenças dos Suínos/epidemiologia
8.
Trop Anim Health Prod ; 53(2): 322, 2021 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-33988782

RESUMO

Bovine tuberculosis is an economically important disease with very high zoonotic potential. Single intradermal cervical tuberculin test (SICT) is considered a gold standard assay for the diagnosis of bovine tuberculosis. However, bovines especially buffaloes may produce a false negative result when the animal becomes cell-mediated immune (CMI) anergic in the advanced stage of the disease. In the present study, ELISA and PCR assays were successfully demonstrated to be useful in diagnosing tuberculosis especially in the CMI anergic buffaloes infected with Mycobacterium bovis. ELISA and PCR assays are able to detect 8.94% and 8.13%, respectively, more animals as positive in comparison to standard SICT assay in a selected population of 123 buffaloes. The moderate agreement between SICT and ELISA (k: 0.528; 0.249-0.807), a substantial agreement between SICT and PCR (k: 0.648; 0.364-0.931), and high agreement between ELISA and PCR (k: 0.856; 0.697-1.0) highlight that ELISA and PCR, if used in parallel with SICT, will provide better sensitivity over single assay. Reduction of false negative reactors may help in minimizing the zoonotic threat from bovine tuberculosis especially in disease endemic region where human and livestock interface is quite high.


Assuntos
Doenças dos Bovinos , Mycobacterium bovis , Tuberculose Bovina , Tuberculose , Animais , Búfalos , Bovinos , Ensaio de Imunoadsorção Enzimática/veterinária , Reação em Cadeia da Polimerase/veterinária , Sensibilidade e Especificidade , Tuberculina , Teste Tuberculínico/veterinária , Tuberculose/diagnóstico , Tuberculose/veterinária , Tuberculose Bovina/diagnóstico
9.
J Vet Diagn Invest ; 33(4): 684-694, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33955287

RESUMO

We developed a sandwich ELISA that detects Clostridium botulinum C and D toxins and reverse-transcription real-time PCRs (RT-rtPCRs) that detect botulinum C and D toxin genes, respectively, to replace the mouse bioassay. The toxin genes were closely associated with the toxin molecules and used as surrogates for the presence of toxin. Samples (638) from 103 clinical cases of birds (302) with suspected botulinum toxicity came from wild birds and poultry (9 cases). Samples tested included blood serum, other body fluids, various tissues, gut contents, maggots, water, and sediment. Botulism was diagnosed in 34 cases (all of which had positive samples in the ELISA, the C toxin gene RT-rtPCR, or both assays). Botulism was suspected in 16 cases (each of which had 1 positive sample either in the ELISA or the C toxin gene RT-rtPCR). In the remaining 53 cases, no samples were positive, but botulism could not be excluded in 32 of these cases, whereas there was no indication of botulism or another diagnosis in 21 cases. The D toxin gene was not detected in any of the clinical samples. No C or D toxin genes were detected in 71 pooled cloacal swabs from 213 healthy migratory birds. The use of an ELISA that detects botulinum C and D toxins in combination with a RT-rtPCR for the botulinum C toxin gene can help confirm the diagnosis of botulism in birds.


Assuntos
Doenças das Aves/diagnóstico , Toxinas Botulínicas/isolamento & purificação , Botulismo/veterinária , Patos , Ensaio de Imunoadsorção Enzimática/veterinária , Reação em Cadeia da Polimerase/veterinária , Animais , Animais Selvagens , Toxinas Botulínicas/genética , Botulismo/diagnóstico , Galinhas , Ensaio de Imunoadsorção Enzimática/métodos , Doenças das Aves Domésticas/diagnóstico , Austrália Ocidental
10.
J Vet Diagn Invest ; 33(4): 762-766, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33856244

RESUMO

Fowl adenovirus serotype 4 (FAdV4), the causative agent of hepatitis-hydropericardium syndrome (HPS), has caused major economic losses to the poultry industry worldwide. Although inactivated vaccines have been deployed widely against FAdV4, a DIVA (differentiating infected from vaccinated animals) test specific for FAdV4 has not been available. We synthesized an immunogenic peptide, corresponding to regions 66-88 aa of the 22K nonstructural protein of FAdV4, and used the peptide as coating antigen to develop an indirect ELISA for a DIVA test specific to FAdV4. Specificity analysis showed that the ELISA only reacted with sera against FAdV4, and not with sera against other pathogens tested. Moreover, the ELISA could effectively differentiate FAdV4-infected chickens from vaccinated chickens. In a test of sera from experimentally infected chickens, the ELISA had 95% and 85% concordance with an indirect immunofluorescence assay (indirect IFA) and a commercial ELISA, respectively, and the concordance was 80.5% between the ELISA and the indirect IFA in detecting clinical infection samples. Our peptide-based ELISA provides an efficient DIVA test for FAdV4 in clinical samples.


Assuntos
Infecções por Adenoviridae/veterinária , Aviadenovirus/isolamento & purificação , Galinhas , Ensaio de Imunoadsorção Enzimática/veterinária , Doenças das Aves Domésticas/diagnóstico , Vacinação/veterinária , Infecções por Adenoviridae/diagnóstico , Infecções por Adenoviridae/virologia , Animais , Anticorpos Antivirais/sangue , Ensaio de Imunoadsorção Enzimática/instrumentação , Ensaio de Imunoadsorção Enzimática/métodos , Peptídeos/química , Doenças das Aves Domésticas/virologia , Sorogrupo
11.
J Wildl Dis ; 57(2): 408-412, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33822154

RESUMO

Archived serum samples taken between 1997 and 2017 from 170 American black bears (Ursus americanus) in the Lake Tahoe area between California and Nevada, US, were tested for Toxoplasma antibodies to assess the seroprevalence of this agent. Samples were screened using a commercial porcine Toxoplasma (enzyme-linked immunosorbent assay [ELISA]) modified with Protein A/G peroxidase and compared to a traditional fluorescent antibody test. Results were analyzed to determine if there were differences in seroprevalence based on the test used, sex of bears, or habitat usage (urban-suburban vs. wildland). No significant differences in seroprevalence were attributable to any of these parameters. The overall seropositivity for bears was 36% (62/170), with urban-suburban bears scoring lower (31%; 37/119) than rural-wildland bears (40%; 18/45). Our results strongly support the use of a Protein A/G-modified ELISA for determining Toxoplasma exposure in black bears. We found somewhat lower levels of Toxoplasma antibodies in black bears from this region than in several reports from populations in the eastern US.


Assuntos
Ensaio de Imunoadsorção Enzimática/veterinária , Toxoplasma , Toxoplasmose Animal/diagnóstico , Ursidae/parasitologia , Animais , Ensaio de Imunoadsorção Enzimática/métodos , Nevada , Toxoplasmose Animal/epidemiologia
12.
J Vet Diagn Invest ; 33(4): 664-669, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33890522

RESUMO

In North America, the only endemic focus for Angiostrongylus vasorum (French heartworm) was historically thought to occur in the southeastern part of the island of Newfoundland. However, reports of A. vasorum infection in wild canids in West Virginia, USA, and Nova Scotia, Canada, suggest the introduction of the parasite to mainland North America. We screened for A. vasorum in coyotes from across southern Ontario. Additionally, we evaluated the performance of ELISAs for detection of circulating A. vasorum antigen (Ag-ELISA) and antibodies against A. vasorum (Ab-ELISA) designed for use in sera or blood of foxes for use with coyotes in this region. Autopsies were performed on 397 coyotes, and lung tissue extract prepared from each carcass was tested via both ELISAs. The sensitivity and specificity for both tests were estimated in the absence of a gold standard using a 2-test single population Bayesian model; sensitivity and specificity priors were based on the performance of the assays in foxes in Switzerland. Eight coyotes tested positive for A. vasorum antigen; no animal was antibody positive. The estimated sensitivity and specificity of the Ag-ELISA were 90.8% (95% credible interval [CrI]: 83.8-95.6%) and 95.5% (95% CrI: 93.4-97.2%), respectively. For the Ab-ELISA, the estimated sensitivity and specificity were 41.9% (95% CrI: 32.1-51.9%) and 98.0% (95% CrI: 96.3-99.0%), respectively. Based on these findings and negative postmortem data for the same animals, there is insufficient evidence to suggest the presence of A. vasorum in southern Ontario coyotes.


Assuntos
Angiostrongylus/isolamento & purificação , Anticorpos Anti-Helmínticos/sangue , Antígenos de Helmintos/sangue , Coiotes , Infecções por Strongylida/veterinária , Animais , Teorema de Bayes , Ensaio de Imunoadsorção Enzimática/veterinária , Ontário/epidemiologia , Prevalência , Sensibilidade e Especificidade , Estudos Soroepidemiológicos , Infecções por Strongylida/epidemiologia , Infecções por Strongylida/parasitologia
13.
Comp Immunol Microbiol Infect Dis ; 76: 101647, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33894478

RESUMO

There are few reports about Q fever in horse populations worldwide. This study aimed to detect the C. burnetii infection by serologic and molecular confirmation using commercial ELISA kit and real-time PCR in the East of Iran a region highly endemic. A total of 177 blood samples and 115 vaginal swabs were randomly collected from horses in East of Iran. The sera samples were analyzed for anti C.burnetii Ig G antibodies by a commercial ELISA kit and nucleic acid extraxted from vaginal samples were used to determine the C. burnetii DNA by real-time PCR assay. Antibodies were detected in 5.64 % (10/177) of sera samples and C. burnetii DNA was detected in 7.82 % (9/115) of horse vaginal samples. There was no significant difference in seroprevalence in different sex, age and breed groups. Our study showed that horses could be considered as a mild potential reservoir of C. burnetii which may be effective on horse health status. However, additional studies are needed to assess whether the horse could be considered as a relevant transmission risk indicator for Q fever.


Assuntos
Coxiella burnetii , Doenças dos Cavalos , Febre Q , Animais , Anticorpos Antibacterianos , Coxiella burnetii/genética , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Doenças dos Cavalos/epidemiologia , Cavalos , Irã (Geográfico)/epidemiologia , Febre Q/epidemiologia , Febre Q/veterinária , Estudos Soroepidemiológicos
14.
Res Vet Sci ; 136: 422-429, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33812285

RESUMO

Glyceraldehyde-3-phosphate dehydrogenase C (GapC) of Streptococcus dysgalactiae (S. dysgalactiae) is a highly conserved surface protein that can induce a protective immune response against S. dysgalactiae infection. To investigate the immune response and protective efficacy induced by epitope-vaccines against S. dysgalactiae infection, we constructed epitope-vaccines GTB1, GB1B2, and GTB1B2 using a T cell epitope (GapC63-77, abbreviated as GT) and two B cell epitopes (GapC30-36, abbreviated as GB1, and GapC97-103, abbreviated as GB2), which were identified in GapC1-150 of S. dysgalactiae in tandem by a GSGSGS linker. BALB/c mice were immunized via an intramuscular injection with the epitope vaccines. The levels of the cytokines, IFN-γ, IL-4, and IL-17, secreted by splenic lymphocytes and the antibody levels in the sera of the immunized mice were detected by ELISA. The immunized mice were subsequently challenged with S. dysgalactiae, and the bacterial colonization in the immunized-mouse organs was examined using the plate counting method. The results showed that the level of the cytokines induced by GTB1B2 was lower than that induced by GapC1-150, but higher than that induced by other epitope vaccines. The level of IgG induced by GTB1B2 was lower than that induced by GapC1-150, but higher than the levels induced by other epitope vaccines. The bacterial colonization numbers in the organs of the mice immunized with GTB1B2 were higher those of the mice immunized with GapC1-150, but significantly lower than those from the mice immunized with other epitope-vaccines. Our results demonstrated that the T cell and B cell epitopes in the epitope-vaccines worked synergistically against bacterial challenge. The multi-epitope vaccine, GTB1B2, could induce stronger cellular and humoral immune responses, and provide a better protective effect against S. dysgalactiae infection.


Assuntos
Antígenos de Bactérias/imunologia , Proteínas de Bactérias/imunologia , Imunogenicidade da Vacina , Vacinas Estreptocócicas/imunologia , Streptococcus/imunologia , Animais , Citocinas/imunologia , Ensaio de Imunoadsorção Enzimática/veterinária , Epitopos de Linfócito B/imunologia , Epitopos de Linfócito T/imunologia , Feminino , Camundongos , Camundongos Endogâmicos BALB C
15.
Comp Immunol Microbiol Infect Dis ; 76: 101646, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33845402

RESUMO

West Nile virus (WNV) was recently detected in Culex pipiens mosquitoes in Morocco. The aim of this study was to evaluate the seroprevalence of WNV in humans and in domestic birds in two regions of Morocco by the detection of IgG antibodies. Blood samples were obtained from 91 human patients and 92 domestic birds from September to December 2019. All study samples were tested using competitive enzyme-linked immunosorbent assay (cELISA) and WNV neutralization tests (VNT) were performed on positive sera. Of all samples, 4 (4.39 %) humans and 4 (4.34 %) birds were found to be seropositive for flaviviruses by the cELISA test. The VNT revealed that three of the four human samples detected positive by cELISA contained neutralizing antibodies against WNV. Two bird samples were confirmed positive by VNT. These results show a significant seroprevalence of anti-WNV antibodies and therefore suggest the active circulation and exposure of human and bird populations in the northwest of Morocco.


Assuntos
Febre do Nilo Ocidental , Vírus do Nilo Ocidental , Animais , Anticorpos Antivirais , Aves , Ensaio de Imunoadsorção Enzimática/veterinária , Humanos , Marrocos/epidemiologia , Estudos Soroepidemiológicos , Febre do Nilo Ocidental/epidemiologia , Febre do Nilo Ocidental/veterinária
16.
Comp Immunol Microbiol Infect Dis ; 76: 101655, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33930629

RESUMO

Rabies is a highly fatal viral infection of the central nervous system affecting all warm-blooded animals including humans. To implement the preventive and control measures, it is important to decide the status of anti-rabies antibodies in dogs. Out of 120 serum samples, 47 (39.2 %) serum samples, showed an antibody titre equal to or above the cut off value of 0.5 IU/ml. The maximum number of dogs showed anti-rabies antibody titres equal to or above the cut-off value of 0.5 IU/ml after <1 month pre-exposure to the rabies vaccine. In 15 serum samples of pet dogs, we observed 13 (86.66 %) dogs with protective anti-rabies antibody titre. Statistical analysis suggests that the age of the animal had no significant effect on anti-rabies antibody titre in vaccinated pet dogs. The overall low seroprevalence of anti-rabies antibody in stray dogs indicates their susceptibility to rabies infection and thus posing a risk of rabies to other animals and humans.


Assuntos
Doenças do Cão , Vacinas Antirrábicas , Raiva , Animais , Animais Domésticos , Anticorpos Antivirais , Doenças do Cão/epidemiologia , Cães , Ensaio de Imunoadsorção Enzimática/veterinária , Raiva/epidemiologia , Raiva/veterinária , Estudos Soroepidemiológicos , Vacinação/veterinária
17.
Res Vet Sci ; 136: 527-534, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33882381

RESUMO

Oxytocin is currently of high interest as a biomarker of welfare and stress in humans and animals. The purpose of this study was to validate two new assays (one using a monoclonal antibody and the other using a polyclonal antibody) for the oxytocin measurement in the saliva of dogs. For this purpose, an analytical validation was performed, and these assays were applied in an experimental trial in which dogs were stroked by their owners. In the experimental trial, saliva samples of 17 dogs were collected by the owners at three different times: a basal sample, at the end of 10 min of an affiliative interaction with their owners consisting of stroking and 15 min after the end of the affiliative interaction. The dogs were separated into two groups (group 1, n = 8 and group 2, n = 9) according to the acceptance of the sponge and the response to the stroking. Significant differences in the response of salivary oxytocin after stroking in the two groups were found when the assay with the monoclonal antibody was used. This assay showed a significant increase just after the end of affiliative interaction (P < 0.01) and 15 min after (P < 0.01) in those dogs that had a good acceptance of the sponge and the stroking induced a positive response on them (based in a Likert-type scale from 1 to 10). These data reflect that the assays used in this study can lead to different results when quantifying oxytocin in the saliva of dogs after stroking.


Assuntos
Cães/fisiologia , Ensaio de Imunoadsorção Enzimática/veterinária , Ocitocina/análise , Animais de Estimação/fisiologia , Saliva/química , Animais , Anticorpos/imunologia , Anticorpos Monoclonais/imunologia , Biomarcadores , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Masculino
18.
Res Vet Sci ; 136: 587-594, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33892367

RESUMO

This study investigated the pathogenesis of infectious bronchitis virus (Gammacoronavirus) strain Q1 in two commercial broiler chicken lines, and the host immune response to infection. Chicks from each line were grouped into either infected or control. Following Q1 infection at day-old, fast (Line-A) and slow (Line-B) growing chicks were monitored for clinical signs and body weights. At 3, 7, 9, 14, 21 and 28 days post infection (dpi), five birds were humanely euthanised, and trachea, kidney and proventriculus tissues were collected for quantitative RT-PCR and histopathology. Blood was collected weekly to determine IBV-specific ELISA antibody titres. Q1 infection significantly reduced the body weights of Line-A chicks at 14 and 21 dpi, but there were no significant differences in Line-B. Through qRT-PCR, significantly higher viral loads were found in the trachea, proventriculus and kidney tissues of Line-A chicks at 7-9 dpi. At day-old and at 28 dpi, the mean antibody titre in Line-B was notably higher than Line-A. Significant IFN-α mRNA expression was noted in the trachea and kidneys of Line-A, whereas no change occurred in Line-B. Chicks in Line-B, compared to those in Line-A, demonstrated a tissue-dependent increase of IFN-ß, TLR3, IL-1ß and IL-6 and LITAF gene transcription responses to IBV Q1. It appears that the level of maternal antibodies, growth rates, and other inherent host genetic factors could have influenced the differences in viral loads and immune responses.


Assuntos
Galinhas/imunologia , Infecções por Coronavirus/veterinária , Vírus da Bronquite Infecciosa/imunologia , Doenças das Aves Domésticas/virologia , Animais , Galinhas/virologia , Infecções por Coronavirus/imunologia , Ensaio de Imunoadsorção Enzimática/veterinária , Imunidade , Doenças das Aves Domésticas/imunologia , Carga Viral/veterinária
19.
Trop Biomed ; 38(1): 28-32, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33797520

RESUMO

Infectious bronchitis viral (IBV) (Avian coronavirus) diseases is among the major reproductive diseases affecting the avian production in Africa. There is scanty information on its current status and vaccination compliance among captive wild birds (CWB) and indigenous chickens (LC) in Nigeria. This study aimed to assess the exposure and the risk factors associated with IBV in CWB and LC from North-central and South west regions of Nigeria. Sera samples from 218 LC and 43 CWB were examined for IBV IgG using enzyme linked immunosorbent assay. Also, owners of LC and managers of CWB were interviewed using a pre-tested structured checklist. An overall IBV prevalence of 42.9% (112/261) was obtained. Captive wild birds and indigenous chickens had 11.6% (5/43) and 49.1% (107/218) prevalence respectively with a significant difference (p< 0.0001, OR= 7.3, 95% CI= 2.8-19.3). Also, geo-location indicated significant difference in IBV exposure among birds (p<=0.034). Furthermore, the study showed that there had never been laboratory screening on all acquired wild birds for exposure to infectious agents in the study location while none of these birds (LB/CWB) had history of vaccination. Since IBV is endemic in Nigeria, the use of vaccine for prophylactic measure should be advocated among LC and CWB owners in order to avoid unnecessary losses. Also, the essence of screening for infectious agents in newly acquired wild birds should be considered crucial for health sustenance and public safety.


Assuntos
Animais Selvagens/virologia , Galinhas/virologia , Infecções por Coronavirus/veterinária , Vírus da Bronquite Infecciosa , Animais , Animais Selvagens/imunologia , Galinhas/imunologia , Infecções por Coronavirus/epidemiologia , Ensaio de Imunoadsorção Enzimática/veterinária , Nigéria/epidemiologia , Estudos Soroepidemiológicos
20.
J Zoo Wildl Med ; 52(1): 306-309, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33827190

RESUMO

Banked serum samples from seven okapi (Okapia johnstoni) with known pregnancy status were evaluated using the BioPRYN wild enzyme-linked immunosorbent assay to detect pregnancy-specific protein B (PSPB). Thirty-six serum samples, 18 from known pregnant and 18 from nonpregnant okapi, were analyzed. Using optical density cutoffs, the BioPRYN wild assay demonstrated a sensitivity of 88% (95% confidence interval, 65%-98%) and a specificity of 100% (95% confidence interval, 81%-100%). In one sample, this test confirmed pregnancy as early as 21 days of gestation; however, two pregnant okapi were reported to be not pregnant at 23 and 38 days of gestation, suggesting sensitivity may be lower in early gestation. Sensitivity improved to 100% when samples were evaluated in okapi at 116 days or greater of gestation. Analysis of PSPB can be used to augment pregnancy diagnosis in okapi, a species that is of high conservation value and has documented pregnancy-associated morbidity.


Assuntos
Antílopes/sangue , Ensaio de Imunoadsorção Enzimática/veterinária , Proteínas da Gravidez/sangue , Testes de Gravidez/veterinária , Animais , Antílopes/fisiologia , Feminino , Gravidez
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...