ABSTRACT
Cattle are considered intermediate hosts of Sarcocystis, which can cause clinical signs and lower performance in the acute phase of infection. Sarcocystis spp. are usually not visible to the naked eye during the post mortem inspection. Moreover, fresh microscopic examination and transmission electron microscopy techniques are difficult to apply to large samples. Therefore, extensive studies on Sarcocystis infection in cattle using molecular and serological methods are required. Here, we investigated Sarcocystis spp. infection in cattle using fresh microscopic examination and polymerase chain reaction of myocardium samples and compared the results with the presence of antibodies against Sarcocystis spp. in corresponding serum samples detected using indirect fluorescent antibody test. Microscopic Sarcocystis were observed in 100% of the myocardial samples, and Sarcocystis DNA was present in 86% (43/50) of these samples. Antibodies against Sarcocystis spp. were detected in 96% (48/50) and 80% (40/50) of the serum samples at 1:25 and 1:200 dilutions, respectively. The three associated methods (fresh microscopic examination, PCR and serology) showed good sensitivity and detection for Sarcocystis spp. compared with fresh microscopic examination (only), and they may facilitate diagnosis in live animals on a large scale as well as monitoring of the herd status.
Os bovinos são considerados hospedeiros intermediários de Sarcocystis, podendo causar sinais clínicos e menor desempenho na fase aguda da infecção. Sarcocystis spp. geralmente não são visíveis a olho nu durante a inspeção post mortem. Além disso, o exame microscópico a fresco e as técnicas de microscopia eletrônica de transmissão são difíceis de aplicar a uma amostras de grande tamanho. Portanto, são necessários extensos estudos sobre a infecção por Sarcocystis em bovinos usando métodos moleculares e sorológicos. Aqui, investigamos a infecção de Sarcocystis spp. em bovinos por meio de exame microscópico a fresco e reação em cadeia da polimerase de amostras de miocárdio e comparado os resultados com a presença de anticorpos contra Sarcocystis spp. em amostras de soro correspondentes detectadas usando o teste de anticorpos fluorescentes indiretos. Sarcocistos microscópicos foram observados em 100% das amostras de miocárdio, e o DNA de Sarcocystis estava presente em 86% (43/50) dessas amostras. Anticorpos contra Sarcocystis spp. foram detectados em 96% (48/50) e 80% (40/50) das amostras de soro nas diluições 1:25 e 1:200, respectivamente. Os três métodos associados (exame microscópico a fresco, PCR e sorologia) mostraram boa sensibilidade e detecção para Sarcocystis spp. em comparação com o exame microscópico fresco (apenas) e podem facilitar o diagnóstico em animais vivos em larga escala, bem como o monitoramento do status do rebanho.
Subject(s)
Animals , Cattle , Cattle Diseases/parasitology , Sarcocystis/isolation & purification , Sarcocystosis/diagnosis , Sarcocystosis/veterinary , Sarcocystosis/epidemiology , Polymerase Chain Reaction/veterinaryABSTRACT
Cattle are broadly deemed a source of Coxiella burnetii; however, evidence reinforcing their role in human infection is scarce. Most published human Q fever outbreaks relate to exposure to small ruminants, notably goats. Anti-phase II C. burnetii IgG and IgM were measured by indirect fluorescent antibody tests in 27 farm and veterinary diagnostic laboratory workers to ascertain whether occupational exposure to cattle aborting due to C. burnetii was the probable source of exposure. Four serological profiles were identified on the basis of anti-phase II IgG and IgM titres. Profile 1, characterised by high IgM levels and concurrent, lower IgG titres (3/27; 11.1%); Profile 2, with both isotypes with IgG titres higher than IgM (2/27; 7.4%); Profile 3 with only IgG phase II (5/27; 18.5%); and Profile 4, in which neither IgM nor IgG were detected (17/27; 63.0%). Profiles 1 and 2 are suggestive of recent C. burnetii exposure, most likely 2.5-4.5 months before testing and, hence, during the window of exposure to the bovine abortions. Profile 3 suggested C. burnetii exposure that most likely predated the window of exposure to aborting cattle, while Profile 4 represented seronegative individuals and, hence, likely uninfected. This study formally linked human Q fever to exposure to C. burnetii infected cattle as a specific occupational hazard for farm and laboratory workers handling bovine aborted material.
ABSTRACT
The direct-fluorescent antibody test (dFAT) is considered the "gold standard" assay to diagnose rabies. However, it is crucial to develop molecular techniques, such as RT-PCR and RT-qPCR, since many laboratories lack the needed supplies for performing complementary methods (viral isolation, for example). For this purpose, diagnostic techniques must be specific and sensitive to guarantee accuracy. This present investigation aimed to detect rabies virus (RABV) in 126 clinically suspected cattle in Brazil using different diagnostic tests [dFAT, mouse inoculation test (MIT), immunohistochemistry (IHC), RT-PCR and RT-qPCR] and to compare those results obtained under routine laboratory conditions. The results of the present investigation demonstrate that the molecular techniques are more sensitive and may detect low viral load, even though the non-homogeneous viral distribution caused a false-negative result in dFAT. We also observed a usual alteration in antigens distribution among regions of the central nervous system (CNS). By both dFAT and IHC assays, the most reliable CNS structures were thalamus and midbrain. Although this investigation demonstrated diagnostic sensitivity and specificity close to 100 % in all laboratory techniques employed, a dFAT auxiliary test is required for bovine specimens, such as molecular techniques, when there are poor sampling conditions (low viral load combined with unavailability of brainstem structures).
Subject(s)
Cattle Diseases/diagnosis , Clinical Laboratory Techniques/methods , Immunologic Tests/methods , Rabies/diagnosis , Rabies/veterinary , Animals , Brazil , Cattle , Cattle Diseases/virology , Disease Models, Animal , Fluorescent Antibody Technique, Direct/methods , Immunohistochemistry/methods , Mice , Rabies/immunology , Rabies/virology , Rabies virus/immunology , Real-Time Polymerase Chain Reaction/methods , Reverse Transcriptase Polymerase Chain Reaction/methods , Sensitivity and Specificity , Viral LoadABSTRACT
BACKGROUND: Toxoplasmosis is an important disease affecting captive non-human primates. The goal of this study was to assess the seroprevalence and pathological findings of toxoplasmosis in different species of captive primates. METHODS: Six captive neotropical primates died naturally due to Toxoplasma gondii infection and were necropsied. Tissue samples were evaluated by histopathology and immunohistochemistry. Serum samples from 57 captive neotropical and Old-world primates housed at the Belo Horizonte zoological garden were analyzed by indirect fluorescent antibody test (IFAT), enzyme-linked immunosorbent assay (ELISA), and indirect hemagglutination assay (IHA). RESULTS: Neotropical primates had lesions compatible with toxoplasmosis with immunolabeled intralesional T gondii. All Old-World primates (10/10), but only three neotropical primates (3/47), all belonging to the Sapajus apella species (3/6), were serologically positive. CONCLUSIONS: Our results suggest a higher susceptibility of neotropical primates to toxoplasmosis. However, this study also supports the hypothesis that Sapajus apella may be naturally resistant.
Subject(s)
Host Specificity , Monkey Diseases , Pitheciidae , Toxoplasma/physiology , Toxoplasmosis, Animal/diagnosis , Animals , Animals, Zoo , Aotus trivirgatus , Brazil , Fatal Outcome , Female , Leontopithecus , Male , Toxoplasmosis, Animal/parasitologyABSTRACT
Fluorescein isothiocyanate (FITC) labelled anti-rabies virus ribonucleoprotein (RNP) antibodies can be used as immunoreagents in direct fluorescent antibody testing (dFAT) for rabies diagnoses. While in-house products are occasionally used by laboratories, most conjugates are commercial reagents. Commercial anti-RNP antibodies are only available for research purposes in Brazil, however, which contributes to the increasing use of in-house produced antibodies. Considering that conjugate quality may influence the results obtained during rabies diagnosis, we sought to analyze the performance requirements of in-house produced polyclonal anti-RNP IgG-FITC for application in dFAT. To that end, their reproducibility, diagnostic sensitivity, and specificity were evaluated. The titer of polyclonal anti-RNP IgG-FITC was initially determined and evaluated by dFAT, using central nervous system (CNS) samples of different animal species (dogs, cats, bovines, equines, bats, and non-human primates). As our main result, the polyclonal anti-RNP IgG-FITC reached a titer of 1:30/1:40 in dFAT, with 100% of diagnostic sensitivity and specificity. In terms of reproducibility, the antibodies, regardless the production batch, presented the same performances. In conclusion, the in-house produced polyclonal anti-RNP IgG-FITC proved suitable for rabies virus antigen detection by dFAT.
Subject(s)
Antibodies, Viral/immunology , Rabies virus/isolation & purification , Rabies/diagnosis , Ribonucleoproteins/immunology , Animals , Antibodies, Viral/chemistry , Antigens, Viral/analysis , Antigens, Viral/immunology , Brazil , Fluorescein-5-isothiocyanate/chemistry , Fluorescent Antibody Technique, Direct , Immunoglobulin G/chemistry , Immunoglobulin G/immunology , Rabies virus/immunology , Reproducibility of Results , Sensitivity and SpecificityABSTRACT
Abstract Neospora caninum is an obligate intracellular parasite that can infect many domestic and wild animals, including birds. These animals are important sources for monitoring of environmental contamination, as they could become infected through sporulated oocysts; however, the real role of birds in the biological cycle of N. caninum remains uncertain. This study aimed to determine the prevalence of anti-N. caninum antibodies, evaluate associated factors, detect the parasite by molecular testing of free-range chickens from Brazil, and evaluate different techniques for its serological diagnosis. Blood samples of 366 chickens from 25 farms were collected for serological assays. The indirect fluorescent antibody test (IFAT) and the indirect enzyme-linked immunosorbent assay (ELISA) were used to detect anti-N. caninum antibodies. Chickens that tested seropositive by IFAT had their brain tissues and a pool of organs (heart, lung, and liver) submitted to PCR for molecular detection of the parasite. Out of 366 chickens, 65 (17.8%) and 163 (44.6%) were seropositive by IFAT and ELISA, respectively. Brain tissues (n=60) and the pools of organs (n=65) were negative in the PCR. Our results showed a high prevalence of antibodies in free-range chickens and that IFAT is the more sensitive technique for the detection of anti-N. caninum antibodies.
Resumo Neospora caninum é um parasita intracelular obrigatório que pode infectar vários animais domésticos e silvestres, incluindo as aves. Esses animais são importantes fontes para o monitoramento da contaminação ambiental, uma vez que eles podem se infectar por meio da ingestão de oocistos. Porém, o real papel das aves no ciclo biológico do N. caninum ainda é incerto. Este estudo teve como objetivos determinar a prevalência de anticorpos anti-N. caninum, avaliar fatores associados, detectar o parasita por meio de teste molecular em galinhas de vida livre do Brasil e avaliar diferentes técnicas para o diagnóstico sorológico. Amostras de sangue de 366 galinhas de 25 fazendas foram coletadas para testes sorológicos. A reação de imunofluorescência indireta (RIFI) e o ensaio de imunoabsorção enzimática (ELISA) foram utilizados para detectar anticorpos anti-N. caninum. As amostras de tecidos (cérebro, coração, pulmão e fígado) de galinhas soropositivas na RIFI foram coletadas e submetidas à PCR para detecção molecular do parasita. Das 366 galinhas, 65 (17,8%) e 163 (44,6%) foram soropositivas pela RIFI e ELISA, respectivamente. Nenhuma amostra foi positiva na PCR. Esses resultados demonstram uma elevada prevalência de anticorpos em galinhas de vida livre e que a RIFI é uma técnica mais sensível para a detecção de anticorpos anti-N. caninum.
Subject(s)
Animals , Coccidiosis/diagnosis , Coccidiosis/veterinary , Coccidiosis/epidemiology , Neospora/genetics , Neospora/immunology , Brazil/epidemiology , Enzyme-Linked Immunosorbent Assay/veterinary , Antibodies, Protozoan/blood , Seroepidemiologic Studies , Chickens , Polymerase Chain Reaction/veterinary , Sensitivity and Specificity , Fluorescent Antibody Technique, Indirect/veterinaryABSTRACT
Neospora caninum is an obligate intracellular parasite that can infect many domestic and wild animals, including birds. These animals are important sources for monitoring of environmental contamination, as they could become infected through sporulated oocysts; however, the real role of birds in the biological cycle of N. caninum remains uncertain. This study aimed to determine the prevalence of anti-N. caninum antibodies, evaluate associated factors, detect the parasite by molecular testing of free-range chickens from Brazil, and evaluate different techniques for its serological diagnosis. Blood samples of 366 chickens from 25 farms were collected for serological assays. The indirect fluorescent antibody test (IFAT) and the indirect enzyme-linked immunosorbent assay (ELISA) were used to detect anti-N. caninum antibodies. Chickens that tested seropositive by IFAT had their brain tissues and a pool of organs (heart, lung, and liver) submitted to PCR for molecular detection of the parasite. Out of 366 chickens, 65 (17.8%) and 163 (44.6%) were seropositive by IFAT and ELISA, respectively. Brain tissues (n=60) and the pools of organs (n=65) were negative in the PCR. Our results showed a high prevalence of antibodies in free-range chickens and that IFAT is the more sensitive technique for the detection of anti-N. caninum antibodies.(AU)
Neospora caninum é um parasita intracelular obrigatório que pode infectar vários animais domésticos e silvestres, incluindo as aves. Esses animais são importantes fontes para o monitoramento da contaminação ambiental, uma vez que eles podem se infectar por meio da ingestão de oocistos. Porém, o real papel das aves no ciclo biológico do N. caninum ainda é incerto. Este estudo teve como objetivos determinar a prevalência de anticorpos anti-N. caninum, avaliar fatores associados, detectar o parasita por meio de teste molecular em galinhas de vida livre do Brasil e avaliar diferentes técnicas para o diagnóstico sorológico. Amostras de sangue de 366 galinhas de 25 fazendas foram coletadas para testes sorológicos. A reação de imunofluorescência indireta (RIFI) e o ensaio de imunoabsorção enzimática (ELISA) foram utilizados para detectar anticorpos anti-N. caninum. As amostras de tecidos (cérebro, coração, pulmão e fígado) de galinhas soropositivas na RIFI foram coletadas e submetidas à PCR para detecção molecular do parasita. Das 366 galinhas, 65 (17,8%) e 163 (44,6%) foram soropositivas pela RIFI e ELISA, respectivamente. Nenhuma amostra foi positiva na PCR. Esses resultados demonstram uma elevada prevalência de anticorpos em galinhas de vida livre e que a RIFI é uma técnica mais sensível para a detecção de anticorpos anti-N. caninum.(AU)
Subject(s)
Animals , Chickens/parasitology , Fluorescent Antibody Technique, Indirect , Enzyme-Linked Immunosorbent Assay , Neospora/classificationABSTRACT
Polyclonal or monoclonal antibodies against rabies virus ribonucleoprotein (RNP) conjugated to fluorescein isothiocyanate (FITC) have been employed for Rabies virus (RABV) antigen detection by the direct fluorescent antibody test (DFA). To date, these biomolecules have been purified by traditional methods such as precipitation by ammonium sulfate or ion exchange chromatography followed by ammonium sulfate precipitation, which allows only for partial detection of the protein of interest. In this study, we aimed to purify anti-RNP polyclonal horse IgG antibodies by cation-exchange chromatography in combination with a homemade immunoaffinity chromatography on RNP immobilized (RNP-IAC). Furthermore, to evaluate the accuracy of the prepared anti-RNP IgG fluorescent antibody in diagnostic purposes, DFA was applied for RABV antigen detection in suspected brain samples of different animal species. The combination of these two techniques made it possible to obtain antibodies with high selectivity and purity. Compared with the performance of the traditional method, anti-RNP IgG antibodies purified by RNP-IAC can be obtained from a smaller volume of hyperimmune serum and with greater avidity. Furthermore, the results obtained by DFA analyses revealed that the prepared anti-RNP IgG fluorescent antibody achieved 100% diagnostic specificity and sensitivity for RABV antigen detection. Thus, two-technique chromatographic, including RNP-IAC technology could be appropriate methods for the purification of polyclonal anti-RNP IgG for the use as a diagnostic reagent for rabies.
Subject(s)
Antibodies, Antinuclear/immunology , Chromatography, Affinity/methods , Immunoglobulin G/immunology , Rabies virus/immunology , Rabies/diagnosis , Ribonucleoproteins/immunology , Animals , Antibodies, Monoclonal/immunology , Antibodies, Viral/immunology , Antigens, Viral/immunology , Cats , Cattle , Cell Line , Chiroptera , Dogs , Haplorhini , Horses , Rabies/immunology , Rabies/virology , Rabies virus/physiology , Sensitivity and Specificity , Species SpecificityABSTRACT
Neospora caninum is a coccidian parasite originally reported in dogs and widely prevalent in numerous species of wild and domestic animals and has as definitive hosts some species of canids. The white-lipped peccary (WLP) ( Tayassu pecari) is a Tayassuidae mammal, found from Mexico to south of Brazil and north of Argentina. It is a game species with great economic importance in the Peruvian Amazon. Blood samples from 101 WLPs were collected from near or within three different conservation reserves located in the southeastern region of the Peruvian Amazon. For the detection of antibodies against N. caninum, indirect fluorescent antibody tests (IFAT) were performed using collared peccary ( Pecari tajacu) and swine ( Sus scrofa domesticus) heterologous secondary antibodies. For both IFAT tests, the cutoff was 1:50. Positive samples were titrated by a two fold serial dilution. In addition to IFAT, samples were also analyzed using an immunoblotting test (IB) with anti-swine conjugate. To confirm the viability of the anti-swine conjugate, the results of these samples previously tested by a modified agglutination test (MAT) for Toxoplasma gondii were used as reference. From the total of 101 samples tested, 5 (4.9%) were N. caninum positive by the three tests and an extra sample was positive by both IFATs and negative in the IB. Comparing both IFATs and considering IB as the gold standard, the relative sensitivity of IFATs was 100%, the specificity was 98.9%, the positive predictive value was 83.3%, and the negative predictive value was 100%. The agreement between tests was characterized by a κ value of 0.904 (95% confidence interval, 0.717 to 1.0) and an SE of 0.095. This is the first report of N. caninum antibodies in free-ranging T. pecari, and swine and collared peccary conjugate can be used as a secondary antibody for detection of antibodies in Tayassu species.
Subject(s)
Antibodies, Protozoan/blood , Artiodactyla , Coccidiosis/veterinary , Fluorescent Antibody Technique, Indirect/veterinary , Neospora , Toxoplasmosis, Animal/epidemiology , Animals , Animals, Wild , Brazil , Coccidiosis/blood , Coccidiosis/epidemiology , Peru/epidemiology , Sensitivity and Specificity , Seroepidemiologic Studies , Toxoplasma/immunology , Toxoplasmosis, Animal/bloodABSTRACT
O objetivo desse trabalho foi determinar a ocorrência de anticorpos IgG para Neospora caninum bem como avaliar os fatores de risco associados à infecção em rebanhos ovinos do estado de Sergipe, Brasil. Foram coletadas, nos anos de 2011 e 2012, 1200 amostras de sangue de ovinos oriundos de sessenta propriedades distribuídas em três mesorregiões do estado para pesquisa de anticorpos para N. caninum pela Reação de Imunofluorescência Indireta (RIFI) utilizando-se como ponto de corte de 50 e as amostras diluídas na base 2. Os dados de 34 variáveis estudadas foram obtidos a partir de questionários aplicados aos proprietários e analisados para se determinar a frequências absolutas e relativas e análise dos fatores de risco pelo teste Qui-quadrado de Pearson (p≤0,05). A ocorrência de ovinos soropositivos para N. caninum foi de 39,83% (478/1200). Em relação às mesorregiões a ocorrência de animais e propriedades positivas foi de, respectivamente, 55,88% (380/680) e 88,24% (30/34) na Leste; 21,42% (60/280) e 42,85% (6/14) no Agreste e 15,83% (38/240) e 41,67% (5/12) no Sertão. Os títulos de anticorpos variaram de 50, representando 96,02% (459/478) das amostras soropositivas, a 6400 (1/478). Dentre as variáveis significantes, na analise multivariada, que foram consideradas com fatores de risco para a infecção pelo N. caninum estavam propriedades localizadas na mesorregião Leste (p=0,000, OR=4,64, IC95%=3,36-6,41), presença de fonte de água parada e corrente (p=0,000 OR=2,03, IC95%=1,41-2,92), ausência de quarentena (p=0,000 OR=2,71, IC95%=2,08-3,53), não utilização de esterqueiras (p=0,000 OR=3,14, IC95%=2,45-4,02), criações com finalidade de subsistência (p=0,000 OR=4,99, IC95%=3,15-7,92), de reprodução (p=0,002, OR=1,74, IC95%=1,22-2,49), presença de cães (p=0,000 OR=2,74, IC95%=1,73-433) e circulação de animais silvestres nos rebanhos (p=0,000 OR=3,45, IC95%=2,44-4,87). Os resultados evidenciam a ocorrência de N. caninum em rebanhos ovinos sergipanos, demonstrando o manejo e a localização dos rebanhos no estado como importantes fatores de risco.(AU)
The aim of this study was to determine the occurrence of antibodies IgG against Neospora caninumand evaluate the risk factors associated with the infection in ovine herds, State of Sergipe, Brazil. Blood samples (n=1200) were collected from sheep raised in 60 sheep run located in the three mesoregions of the State of Sergipe, between 2011 e 2012. Antibodies were investigated by Indirect Immunofluorescence Antibody Test of which cutoff point was 50 and positive samples were diluted in base 2 until the last positive titer. Data from 15 variables was obtained from questionnaires given to farmers. Absolute and relative frequencies were determined and the risk factors were analyzed by Pearson's Qui-Square test (p≤0,05). The occurrences of serum reactive sheep were 39.83% (478/1200). The occurrences of positive sheep and sheep run were 55.88% (380/680) and 88.24% (30/34) in the Eastern region; 21.42% (60/280) e 42.85% (6/14) in dry region and 15.83% (38/240) e 41.67% (5/12) in the backwoods respectively. Antibody titers ranged from 50 (n=459), represented 96.02% (459/478) of seropositive samples to 6400 (1/478). Among the significant variables in the multivariate analysis were considered risk factors for infection with N. caninum were, sheep run located in Eastern region (p=0.000, OR=4.64, CI95%=3.36-6.41); standing and running water sources (p=0.000 OR=2.03, CI95%=1.41-2.92), absence of quarantine (p=0.000, OR=2.71, CI95%=2.08-3.53), absence of dunghill (p=0.000, OR=3.14, CI95%=2.45-4.02), presence of dogs (p=0.000, OR=2.74, CI95%=1.73-433), presence of wild animals (p=0.000, OR=3.45, CI95%=2.44-4.87) and subsistence (p=0.000, OR=4.99, CI95%=3.15-7.92) or reproduction (p=0.002, OR=1.74, CI95%=1.22-2.49) livestock were important risk factors. Our results highlight the occurrence ofN. caninumin the ovine herds from State of Sergipe. Management and location of sheep runs were important risk factors associated to the infection.(AU)
Subject(s)
Animals , Sheep/parasitology , Risk Factors , Coccidiosis/epidemiology , Neospora , Brazil , Fluorescent Antibody Technique, Indirect/veterinaryABSTRACT
O objetivo desse trabalho foi determinar a ocorrência de anticorpos IgG para Neospora caninum bem como avaliar os fatores de risco associados à infecção em rebanhos ovinos do estado de Sergipe, Brasil. Foram coletadas, nos anos de 2011 e 2012, 1200 amostras de sangue de ovinos oriundos de sessenta propriedades distribuídas em três mesorregiões do estado para pesquisa de anticorpos para N. caninum pela Reação de Imunofluorescência Indireta (RIFI) utilizando-se como ponto de corte de 50 e as amostras diluídas na base 2. Os dados de 34 variáveis estudadas foram obtidos a partir de questionários aplicados aos proprietários e analisados para se determinar a frequências absolutas e relativas e análise dos fatores de risco pelo teste Qui-quadrado de Pearson (p≤0,05). A ocorrência de ovinos soropositivos para N. caninum foi de 39,83% (478/1200). Em relação às mesorregiões a ocorrência de animais e propriedades positivas foi de, respectivamente, 55,88% (380/680) e 88,24% (30/34) na Leste; 21,42% (60/280) e 42,85% (6/14) no Agreste e 15,83% (38/240) e 41,67% (5/12) no Sertão. Os títulos de anticorpos variaram de 50, representando 96,02% (459/478) das amostras soropositivas, a 6400 (1/478). Dentre as variáveis significantes, na analise multivariada, que foram consideradas com fatores de risco para a infecção pelo N. caninum estavam propriedades localizadas na mesorregião Leste (p=0,000, OR=4,64, IC95%=3,36-6,41), presença de fonte de água parada e corrente (p=0,000 OR=2,03, IC95%=1,41-2,92), ausência de quarentena (p=0,000 OR=2,71, IC95%=2,08-3,53), não utilização de esterqueiras (p=0,000 OR=3,14, IC95%=2,45-4,02), criações com finalidade de subsistência (p=0,000 OR=4,99, IC95%=3,15-7,92), de reprodução (p=0,002, OR=1,74, IC95%=1,22-2,49), presença de cães (p=0,000 OR=2,74, IC95%=1,73-433) e circulação de animais silvestres nos rebanhos (p=0,000 OR=3,45, IC95%=2,44-4,87). Os resultados evidenciam a ocorrência de N. caninum em rebanhos ovinos sergipanos, demonstrando o manejo e a localização dos rebanhos no estado como importantes fatores de risco.(AU)
The aim of this study was to determine the occurrence of antibodies IgG against Neospora caninumand evaluate the risk factors associated with the infection in ovine herds, State of Sergipe, Brazil. Blood samples (n=1200) were collected from sheep raised in 60 sheep run located in the three mesoregions of the State of Sergipe, between 2011 e 2012. Antibodies were investigated by Indirect Immunofluorescence Antibody Test of which cutoff point was 50 and positive samples were diluted in base 2 until the last positive titer. Data from 15 variables was obtained from questionnaires given to farmers. Absolute and relative frequencies were determined and the risk factors were analyzed by Pearson's Qui-Square test (p≤0,05). The occurrences of serum reactive sheep were 39.83% (478/1200). The occurrences of positive sheep and sheep run were 55.88% (380/680) and 88.24% (30/34) in the Eastern region; 21.42% (60/280) e 42.85% (6/14) in dry region and 15.83% (38/240) e 41.67% (5/12) in the backwoods respectively. Antibody titers ranged from 50 (n=459), represented 96.02% (459/478) of seropositive samples to 6400 (1/478). Among the significant variables in the multivariate analysis were considered risk factors for infection with N. caninum were, sheep run located in Eastern region (p=0.000, OR=4.64, CI95%=3.36-6.41); standing and running water sources (p=0.000 OR=2.03, CI95%=1.41-2.92), absence of quarantine (p=0.000, OR=2.71, CI95%=2.08-3.53), absence of dunghill (p=0.000, OR=3.14, CI95%=2.45-4.02), presence of dogs (p=0.000, OR=2.74, CI95%=1.73-433), presence of wild animals (p=0.000, OR=3.45, CI95%=2.44-4.87) and subsistence (p=0.000, OR=4.99, CI95%=3.15-7.92) or reproduction (p=0.002, OR=1.74, CI95%=1.22-2.49) livestock were important risk factors. Our results highlight the occurrence ofN. caninumin the ovine herds from State of Sergipe. Management and location of sheep runs were important risk factors associated to the infection.(AU)
Subject(s)
Animals , Sheep/parasitology , Risk Factors , Coccidiosis/epidemiology , Neospora , Brazil , Fluorescent Antibody Technique, Indirect/veterinaryABSTRACT
ABSTRACT: The aim of this study was to determine the occurrence of antibodies IgG against Neospora caninumand evaluate the risk factors associated with the infection in ovine herds, State of Sergipe, Brazil. Blood samples (n=1200) were collected from sheep raised in 60 sheep run located in the three mesoregions of the State of Sergipe, between 2011 e 2012. Antibodies were investigated by Indirect Immunofluorescence Antibody Test of which cutoff point was 50 and positive samples were diluted in base 2 until the last positive titer. Data from 15 variables was obtained from questionnaires given to farmers. Absolute and relative frequencies were determined and the risk factors were analyzed by Pearsons Qui-Square test (p0,05). The occurrences of serum reactive sheep were 39.83% (478/1200). The occurrences of positive sheep and sheep run were 55.88% (380/680) and 88.24% (30/34) in the Eastern region; 21.42% (60/280) e 42.85% (6/14) in dry region and 15.83% (38/240) e 41.67% (5/12) in the backwoods respectively. Antibody titers ranged from 50 (n=459), represented 96.02% (459/478) of seropositive samples to 6400 (1/478). Among the significant variables in the multivariate analysis were considered risk factors for infection with N. caninum were, sheep run located in Eastern region (p=0.000, OR=4.64, CI95%=3.36-6.41); standing and running water sources (p=0.000 OR=2.03, CI95%=1.41-2.92), absence of quarantine (p=0.000, OR=2.71, CI95%=2.08-3.53), absence of dunghill (p=0.000, OR=3.14, CI95%=2.45-4.02), presence of dogs (p=0.000, OR=2.74, CI95%=1.73-433), presence of wild animals (p=0.000, OR=3.45, CI95%=2.44-4.87) and subsistence (p=0.000, OR=4.99, CI95%=3.15-7.92) or reproduction (p=0.002, OR=1.74, CI95%=1.22-2.49) livestock were important risk factors. Our results highlight the occurrence ofN. caninumin the ovine herds from State of Sergipe. Management and location of sheep runs were important risk factors associated to the infection.
RESUMO: O objetivo desse trabalho foi determinar a ocorrência de anticorpos IgG para Neospora caninum bem como avaliar os fatores de risco associados à infecção em rebanhos ovinos do estado de Sergipe, Brasil. Foram coletadas, nos anos de 2011 e 2012, 1200 amostras de sangue de ovinos oriundos de sessenta propriedades distribuídas em três mesorregiões do estado para pesquisa de anticorpos para N. caninum pela Reação de Imunofluorescência Indireta (RIFI) utilizando-se como ponto de corte de 50 e as amostras diluídas na base 2. Os dados de 34 variáveis estudadas foram obtidos a partir de questionários aplicados aos proprietários e analisados para se determinar a frequências absolutas e relativas e análise dos fatores de risco pelo teste Qui-quadrado de Pearson (p0,05). A ocorrência de ovinos soropositivos para N. caninum foi de 39,83% (478/1200). Em relação às mesorregiões a ocorrência de animais e propriedades positivas foi de, respectivamente, 55,88% (380/680) e 88,24% (30/34) na Leste; 21,42% (60/280) e 42,85% (6/14) no Agreste e 15,83% (38/240) e 41,67% (5/12) no Sertão. Os títulos de anticorpos variaram de 50, representando 96,02% (459/478) das amostras soropositivas, a 6400 (1/478). Dentre as variáveis significantes, na analise multivariada, que foram consideradas com fatores de risco para a infecção pelo N. caninum estavam propriedades localizadas na mesorregião Leste (p=0,000, OR=4,64, IC95%=3,36-6,41), presença de fonte de água parada e corrente (p=0,000 OR=2,03, IC95%=1,41-2,92), ausência de quarentena (p=0,000 OR=2,71, IC95%=2,08-3,53), não utilização de esterqueiras (p=0,000 OR=3,14, IC95%=2,45-4,02), criações com finalidade de subsistência (p=0,000 OR=4,99, IC95%=3,15-7,92), de reprodução (p=0,002, OR=1,74, IC95%=1,22-2,49), presença de cães (p=0,000 OR=2,74, IC95%=1,73-433) e circulação de animais silvestres nos rebanhos (p=0,000 OR=3,45, IC95%=2,44-4,87). Os resultados evidenciam a ocorrência de N. caninum em rebanhos ovinos sergipanos, demonstrando o manejo e a localização dos rebanhos no estado como importantes fatores de risco.
ABSTRACT
The aim of this study was to examine the intra-uterine exposure to Sarcocystis spp. antigens, determining the number of foals with detectable concentrations of antibodies against these agents in the serum, before colostrum ingestion and collect data about exposure of horses to the parasite. Serum samples were collected from 195 thoroughbred mares and their newborns in two farms from southern Brazil. Parasite specific antibody responses to Sarcocystis antigens were detected using the indirect immunofluorescent antibody test (IFAT) and immunoblot analysis. In 84.1% (159/189) of the pregnant mares and in 7.4% (14/189) of foals we detected antibodies anti-Sarcocystis spp. by IFAT. All samples seropositive from foals were also positive in their respective mares. Serum samples of seropositive foals by IFAT, showed no reactivity on the immunoblot, having as antigens S. neurona merozoites. In conclusion, the intra-uterine exposure to Sarcocystis spp. antigens in horses was demonstrated, with occurrence not only in mares, but also in their foals, before colostrum ingestion these occurrences were reduced.(AU)
O objetivo deste estudo foi avaliar a exposição intrauterina ao Sarcocystis spp., para determinar o número de potros que possuem concentrações detectáveis de anticorpos contra esses agentes no soro, antes da ingestão do colostro, por meio da coleta de dados sobre a exposição a esses protozoários nos equinos. Amostras de soro foram coletadas de 195 éguas puro-sangue e seus respectivos potros recém-nascidos, em duas fazendas localizadas na região Sul do Brasil. Os testes utilizados na detecção de anticorpos específicos para o Sarcocystis foram a reação de imunofluorescência indireta (RIFI) e análise por meio de immunoblot. Pela RIFI, em 84,1% (159/189) das éguas e em 7,4% (14/189) dos potros foram detectados anticorpos anti-Sarcocystis spp. Todas as amostras soropositivas dos potros também foram positivas para suas respectivas mães. As amostras de soro dos potros soropositivos na RIFI, não apresentaram reatividade no immunoblot, tendo como antígenos merozoítos de S. neurona. Em conclusão, foi demonstrada a exposição intrauterina de Sarcocystis spp. em equinos, com ocorrência em éguas, porém, em seus respectivos potros, antes da ingestão de colostro a ocorrência foi reduzida.(AU)
Subject(s)
Animals , Horses/parasitology , Sarcocystis/pathogenicity , Prenatal Diagnosis/veterinary , Antibodies, Protozoan/analysis , Encephalomyelitis/veterinary , Maternal-Fetal Exchange , Seroepidemiologic Studies , Immunoblotting , Immunoblotting/veterinaryABSTRACT
The aim of this study was to examine the intra-uterine exposure to Sarcocystis spp. antigens, determining the number of foals with detectable concentrations of antibodies against these agents in the serum, before colostrum ingestion and collect data about exposure of horses to the parasite. Serum samples were collected from 195 thoroughbred mares and their newborns in two farms from southern Brazil. Parasite specific antibody responses to Sarcocystis antigens were detected using the indirect immunofluorescent antibody test (IFAT) and immunoblot analysis. In 84.1% (159/189) of the pregnant mares and in 7.4% (14/189) of foals we detected antibodies anti-Sarcocystis spp. by IFAT. All samples seropositive from foals were also positive in their respective mares. Serum samples of seropositive foals by IFAT, showed no reactivity on the immunoblot, having as antigens S. neurona merozoites. In conclusion, the intra-uterine exposure to Sarcocystis spp. antigens in horses was demonstrated, with occurrence not only in mares, but also in their foals, before colostrum ingestion these occurrences were reduced.
O objetivo deste estudo foi avaliar a exposição intrauterina ao Sarcocystis spp., para determinar o número de potros que possuem concentrações detectáveis de anticorpos contra esses agentes no soro, antes da ingestão do colostro, por meio da coleta de dados sobre a exposição a esses protozoários nos equinos. Amostras de soro foram coletadas de 195 éguas puro-sangue e seus respectivos potros recém-nascidos, em duas fazendas localizadas na região Sul do Brasil. Os testes utilizados na detecção de anticorpos específicos para o Sarcocystis foram a reação de imunofluorescência indireta (RIFI) e análise por meio de immunoblot. Pela RIFI, em 84,1% (159/189) das éguas e em 7,4% (14/189) dos potros foram detectados anticorpos anti-Sarcocystis spp. Todas as amostras soropositivas dos potros também foram positivas para suas respectivas mães. As amostras de soro dos potros soropositivos na RIFI, não apresentaram reatividade no immunoblot, tendo como antígenos merozoítos de S. neurona. Em conclusão, foi demonstrada a exposição intrauterina de Sarcocystis spp. em equinos, com ocorrência em éguas, porém, em seus respectivos potros, antes da ingestão de colostro a ocorrência foi reduzida.
Subject(s)
Animals , Antibodies, Protozoan/analysis , Horses/parasitology , Prenatal Diagnosis/veterinary , Sarcocystis/pathogenicity , Encephalomyelitis/veterinary , Immunoblotting , Immunoblotting/veterinary , Maternal-Fetal Exchange , Seroepidemiologic StudiesABSTRACT
In South America, capybaras (Hydrochoerus hydrochaeris) as well as coatis (Nasua nasua) are the reservoir hosts of Trypanosoma evansi. Capybaras from a T. evansi nonendemic area in the State of São Paulo, southeastern Brazil, were culled because of an ongoing outbreak of Brazilian spotted fever; serum samples from these capybaras were tested for antibodies to T. evansi. Of the 172 sera tested, 17 (9.9%) were seropositive by card agglutination test, with antibody titers of 1:8-1:128; 14 (8.1%) of these 17 seropositive sera were also seropositive by indirect fluorescent antibody test, with antibody titers of 1:16-1:256. Both serologic techniques proved to be efficient, with similar results for detection of antibodies to T. evansi in capybaras from a nonendemic area in Brazil.
Subject(s)
Rodentia , Trypanosoma/isolation & purification , Trypanosomiasis/veterinary , Agglutination Tests/veterinary , Animals , Brazil/epidemiology , Seroepidemiologic Studies , Trypanosomiasis/epidemiologyABSTRACT
Babesia bovis and Babesia bigemina are causative agents of bovine babesiosis, a tick-borne disease of cattle in tropical and subtropical regions. Babesia spp. infection adversely affects cattle health and can be fatal resulting in considerable economic loss worldwide. Under endemic stability conditions, herds contain high numbers of chronically infected, asymptomatic carrier animals, in which no parasitemia is detected by microscopic blood smear examination. In addition to bovines, also water buffaloes are infected by both Babesia spp. commonly leading to a subclinical infection. The infection rate (by nPCR) and herd exposure (by IFAT) of bovines and water buffaloes reared under similar field conditions in an area of endemic stability were determined and compared. In order to optimize direct parasite detection, highly sensitive nPCR assays were developed and applied, allowing the detection of as little as 0.1 fg DNA of each Babesia pathogen. Significantly lower percentages (p<0.001) of seropositive water buffaloes compared to bovines were observed for B. bovis (71.4% vs. 98%) and B. bigemina (85% vs. 100%). Interestingly, in comparison, differences noticed between water buffaloes and bovines were considerably larger with direct parasite detection by nPCR (16.2% vs. 82.3% and 24% vs. 94.1% for B. bovis and B. bigemina, respectively). As expected, bovines subjected to monthly acaricide applications exhibited a significant lower infection rate as determined by nPCR than bovines not subjected to these measures (B. bovis 33.3% vs. 90.7%, p<0.001; B. bigemina 80% vs. 96.5%, p<0.001, for treated vs. untreated animals). Interestingly no differences between these groups were observed with respect to seropositivity, suggesting similar rates of parasite exposure (B. bovis 100% vs. 97.7%, p<0.001; B. bigemina 100% vs. 100%, p<0.001). Importantly, a significantly higher number of water buffaloes as determined by nPCR were infected when reared jointly with bovines not subjected to tick control than when reared jointly with bovines subjected to tick control (B. bovis 31.6% vs. 9.5%, p<0.01; B. bigemina 42.1% vs. 9.5%, p<0.01, for water buffaloes reared with untreated vs. treated bovines) and/or when reared without bovines (B. bovis 31.6% vs. 11.6%, p<0.01; B. bigemina 42.1% vs. 20%, p<0.01). An accumulation of seropositivity and a decline of infection rates were observed in older animals, while differences observed with regard to gender may warrant further investigation. In summary, our findings suggest that water buffaloes are much more capable to limit or eliminate Babesia infection, possibly due to a more capable immune defense. Furthermore, an increased Babesia spp. parasite reservoir of bovines seems to increase the infection rate of water buffaloes when both are reared on the same pasture.
Subject(s)
Babesia bovis/physiology , Babesia/physiology , Babesiosis/diagnosis , Buffaloes/parasitology , Cattle Diseases/diagnosis , Parasitemia/veterinary , Age Factors , Animals , Antibodies, Protozoan/blood , Babesia/genetics , Babesia/immunology , Babesia bovis/genetics , Babesia bovis/immunology , Babesiosis/epidemiology , Cattle , Cattle Diseases/epidemiology , DNA, Protozoan/genetics , Endemic Diseases/veterinary , Female , Fluorescent Antibody Technique, Indirect/veterinary , Male , Parasitemia/diagnosis , Polymerase Chain Reaction/standards , Polymerase Chain Reaction/veterinary , Prevalence , Sensitivity and Specificity , Sex FactorsABSTRACT
Theileria equi, a protozoon in the phylum Apicomplexa, is the causative agent of equine theileriosis. The aim of this cross-sectional study was to determine the prevalence of IgG antibodies against T. equi, by using the indirect fluorescent antibody test (IFAT) reaction and correlating the serostatus with some epidemiological variables relating to the way in which Mangalarga Marchador horses are raised in southern Minas Gerais, Brazil. In this study, 506 horses were used, all clinically healthy, on 53 horse farms distributed across 27 municipalities in southern Minas Gerais. The statistical tests, comprising the chi-square test and generalized estimating equations (GEE), were performed in the SPSS Statistics 20.0 software. The true seroprevalence of T. equi among the horses was 57.0% (288 out of 506; ranging from 52.1 to 62.0%) and among horse farms, 98.1% (52 out of 53; ranging from 90.3 to 99.9%). The horse farms on which the majority of the horses presented good body condition and which did not use chemical products to kill ticks when new horses were introduced, had horses over the age of 5years, comprised <100ha in area and did not use embryo transfer showed greater seroprevalence of T. equi (p<0.05). The results from this study make it possible to state that infection with T. equi is endemic in the south of Minas Gerais and is widely distributed among horse farms raising Mangalarga Marchador horses. However, these infections are subclinical or chronic.
ABSTRACT
Background Toxoplasmosis is a zoonosis caused by an obligate intracellular parasite, Toxoplasma gondii, which affects warm-blooded animals including humans. Its prevalence rates usually vary in different regions of the planet. Methods In this study, an analysis of the seroprevalence of toxoplasmosis among Brazilian students was proposed by means of IgG specific antibodies detection. The presence of anti-Toxoplasma gondiiantibodies by indirect fluorescent antibody test (IFAT) was also evaluated in order to compare it with enzyme-linked immunosorbent assay (ELISA) and to assess the use of 2,2-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) and o-phenylenediamine dihydrochloride chromogens. Results The IFAT method showed a seroprevalence of 22.3%. These results were similar to those obtained by ELISA (24.1%). The seroprevalence was directly estimated from the IgG avidity, which showed that in a sample of 112 students, three of them had acute infection, an incidence of 1.6% in the studied population. Conclusion In this study, the use of different chromogenic substrates in immunoenzymatic ELISA assays did not display different sensitivity in the detection of T. gondii-reagent serum. The extrapolation of results to this population must be carefully considered, since the investigation was conducted on a reduced sample. However, it allows us to emphasize the importance of careful and well prepared studies to identify risk factors for toxoplasmosis, to adopt preventive measures and to offer guidance to at-risk populations about the disease.(AU)
Subject(s)
Humans , Seroepidemiologic Studies , Toxoplasmosis/epidemiology , Toxoplasmosis/immunology , Toxoplasma/immunologyABSTRACT
Toxoplasmosis and neosporosis have been recognized as economically important diseases with considerable impact on the livestock industry. Little is known concerning the occurrence of Toxoplasma gondii and Neospora caninum in sheep from Tocantins state, Brazil. Here, we investigated antibodies against these parasites and associated factors in 182 sheep from Araguaína, Santa Terezinha do Tocantins, Arguianópolis and Palmeiras do Tocantins districts, Tocantins. Sheep sera were assayed for T. gondii and N. caninum IgG antibodies by indirect fluorescence antibody test (IFAT), using cut-off point at a dilution of 1:40 and 1:25 respectively. The prevalence of seropositive animal for T. gondii was 13.74% and 13.74% for N. caninum. None of the characteristics studied including reproductive problems, presence of cats, presence of dogs and veterinary care (p>0.05) was associated with occurrence of T. gondii or N. caninum infection. Only breed was identified as associated factor for the occurrence of toxoplasmosis in sheep (p<0.05). The present study is the first report on serum occurrence of T. gondii and N. caninum in sheep from the state of Tocantins, Brazil.(AU)
Toxoplasmose e Neosporose são reconhecidas por doenças economicamente importantes com impacto considerável na indústria pecuária. Pouco se sabe sobre a ocorrência de Toxoplasma gondii e Neospora caninum em ovelhas do estado do Tocantins, Brasil. Foram investigados a ocorrência de anticorpos contra estes parasitos e fatores associados em 182 ovelhas das cidades de Araguaína, Santa Terezinha do Tocantins, Arguianópolis e Palmeiras do Tocantins, Tocantins. Os soro das ovelhas foram testados para anticorpos IgG anti-T. gondii e anti-N. caninum pela Reação de Imunofluorescência Indireta (RIFI), usando os pontos de corte na diluição de 1:40 e 1:25, respectivamente. A prevalência de animais soropositivos para T. gondii foi de 13.74% e para N. caninum, 13.74%. Nenhuma das características estudadas incluindo problemas reprodutivos, presença de gatos, presença de cães e cuidados veterinários (p>0.05) foram associadas com a ocorrência infecção por T. gondii ou N. caninum. Somente raça foi identificada como fator associado à ocorrência de toxoplasmose em ovelhas (p<0.05). O presente trabalho é o primeiro relato da ocorrência sérica de T. gondii e N. caninum em ovelhas do estado do Tocantins, Brasil.(AU)
Subject(s)
Animals , Sheep Diseases/parasitology , Sheep/immunology , Antibodies, Protozoan/isolation & purification , Neospora/isolation & purification , Toxoplasma/isolation & purification , Toxoplasmosis, Animal , Fluorescent Antibody Technique, Indirect/veterinaryABSTRACT
Toxoplasmosis and neosporosis have been recognized as economically important diseases with considerable impact on the livestock industry. Little is known concerning the occurrence of Toxoplasma gondii and Neospora caninum in sheep from Tocantins state, Brazil. Here, we investigated antibodies against these parasites and associated factors in 182 sheep from Araguaína, Santa Terezinha do Tocantins, Arguianópolis and Palmeiras do Tocantins districts, Tocantins. Sheep sera were assayed for T. gondii and N. caninum IgG antibodies by indirect fluorescence antibody test (IFAT), using cut-off point at a dilution of 1:40 and 1:25 respectively. The prevalence of seropositive animal for T. gondii was 13.74% and 13.74% for N. caninum. None of the characteristics studied including reproductive problems, presence of cats, presence of dogs and veterinary care (p>0.05) was associated with occurrence of T. gondii or N. caninum infection. Only breed was identified as associated factor for the occurrence of toxoplasmosis in sheep (p<0.05). The present study is the first report on serum occurrence of T. gondii and N. caninum in sheep from the state of Tocantins, Brazil.
Toxoplasmose e Neosporose são reconhecidas por doenças economicamente importantes com impacto considerável na indústria pecuária. Pouco se sabe sobre a ocorrência de Toxoplasma gondii e Neospora caninum em ovelhas do estado do Tocantins, Brasil. Foram investigados a ocorrência de anticorpos contra estes parasitos e fatores associados em 182 ovelhas das cidades de Araguaína, Santa Terezinha do Tocantins, Arguianópolis e Palmeiras do Tocantins, Tocantins. Os soro das ovelhas foram testados para anticorpos IgG anti-T. gondii e anti-N. caninum pela Reação de Imunofluorescência Indireta (RIFI), usando os pontos de corte na diluição de 1:40 e 1:25, respectivamente. A prevalência de animais soropositivos para T. gondii foi de 13.74% e para N. caninum, 13.74%. Nenhuma das características estudadas incluindo problemas reprodutivos, presença de gatos, presença de cães e cuidados veterinários (p>0.05) foram associadas com a ocorrência infecção por T. gondii ou N. caninum. Somente raça foi identificada como fator associado à ocorrência de toxoplasmose em ovelhas (p<0.05). O presente trabalho é o primeiro relato da ocorrência sérica de T. gondii e N. caninum em ovelhas do estado do Tocantins, Brasil.