Resultado da pesquisa (325)
Termo utilizado na pesquisa Bovine
#11 - Bovine neosporosis in Rio Grande do Sul, Brazil: Elevated antibody detection rate in comparison to previous decades
Abstract in English:
This study aimed to determine the frequency of anti-Neospora caninum antibody detection in three samples and sampling methods: A prevalence study, routine diagnostic laboratory samples, and fetal bovine serum samples. These samples were collected from cattle in Rio Grande do Sul (RS), southern Brazil, and analyzed using the indirect immunofluorescence reaction technique. For each sampling method, a historical study was used as a reference for comparison. In the prevalence study, 1,248 serum samples were collected from 2020 to 2022. The prevalence of N. caninum in the RS state was 22.8% (285/1248). This figure was statistically different compared to previous studies conducted in 2002, which reported a prevalence of 11.2% (p<0.001). In the routine diagnostic samples, an average rate of 29.95% (985/3289) of anti-N. caninum antibodies were detected. This rate was statistically higher than that of a previous study conducted in 2003, which reported a rate of 20% (p=0.01). Similar data were found in the fetal bovine serum samples, which showed an increase compared to previous studies conducted in 2010 that reported a rate of 15% (p=0.003). The increase in the detection rate of N. caninum antibodies underscores the need for measures to control and prevent bovine neosporosis.
Abstract in Portuguese:
Este estudo teve como objetivo determinar a frequência de detecção de anticorpos anti-Neospora caninum em três diferentes amostras e métodos de coleta: um estudo de prevalência, amostras de laboratório de diagnóstico de rotina e amostras de soro fetal bovino. Essas amostras foram coletadas de bovinos no Rio Grande do Sul (RS), região Sul do Brasil, e analisadas usando a técnica de reação de imunofluorescência indireta. Para cada método de coleta, um estudo histórico foi usado como referência para comparação. No estudo de prevalência, foram coletadas 1.248 amostras de soro entre 2020 e 2022. A prevalência de N. caninum no estado do RS foi de 22,8% (285/1248). Esse valor foi estatisticamente diferente quando comparado a estudos anteriores realizados em 2002, que relataram uma prevalência de 11,2% (p<0,001). Nas amostras de diagnóstico de rotina, foi detectada uma taxa média de 29,95% (985/3289) de anticorpos anti-N. caninum. Essa taxa foi estatisticamente maior do que a de um estudo anterior realizado em 2003, que relatou uma taxa de 20% (p=0,01). Dados semelhantes foram encontrados nas amostras de soro fetal bovino, que mostraram um aumento em comparação com estudos anteriores realizados em 2010 que relataram uma taxa de 15% (p=0,003). O aumento na taxa de detecção de anticorpos anti-N. caninum destaca a necessidade de medidas para controlar e prevenir a neosporose bovina.
#12 - Exploring the mechanism of quercetin treatment of bovine viral diarrhea mucosal disease based on network pharmacology and in vitro validation
Abstract in English:
Bovine viral diarrhea virus (BVDV) can cause acute and persistent infections in cattle, resulting in significant economic losses to the livestock industry each year. Targeted antiviral therapy is an effective strategy. This study was based on network pharmacology, molecular docking techniques and in vitro studies to investigate quercetin’s mechanism in treating bovine viral diarrhea/mucosal disease (BVD-MD). The network topology analysis was carried out using Cytoscape 3.9.0 software to construct the network of “Chinese medicine ingredients-target-diseases”. Protein interactions were explored and analyzed using the String system (PPI). GO and KEGG pathway analysis of the intersected targets was performed using Bioconductor software. The molecular docking and molecular dynamics simulation methods were used to reveal the degree of binding of quercetin to key target genes. Western blot and indirect immunofluorescence were used to characterize the antiviral effects of quercetin. This study utilized network pharmacological analysis, identifying 22 targets associated with BVD-MD. The results of the KEGG pathway showed that quercetin was closely related to Ras and MAPK signaling pathways of BVD-MD. Molecular docking results showed that SRC, NS5B, NOX4 and XDH were the key targets of quercetin in the treatment of BVD-MD. Through network pharmacology, molecular docking and in vitro experiments, quercetin was demonstrated to combat bovine viral diarrhea mucosal disease through key targets of SRC, MAPK1, GSK3B, NS5B and E2. Molecular dynamics analysis showed that quercetin exhibited complex stability with NS5B. This study provides a theoretical and experimental basis for quercetin treatment of BVD-MD and later drug development.
Abstract in Portuguese:
Bovine viral diarrhea virus (BVDV) can cause acute and persistent infections in cattle, resulting in significant economic losses to the livestock industry each year. Targeted antiviral therapy is an effective strategy. This study was based on network pharmacology, molecular docking techniques and in vitro studies to investigate quercetin’s mechanism in treating bovine viral diarrhea/mucosal disease (BVD-MD). The network topology analysis was carried out using Cytoscape 3.9.0 software to construct the network of “Chinese medicine ingredients-target-diseases”. Protein interactions were explored and analyzed using the String system (PPI). GO and KEGG pathway analysis of the intersected targets was performed using Bioconductor software. The molecular docking and molecular dynamics simulation methods were used to reveal the degree of binding of quercetin to key target genes. Western blot and indirect immunofluorescence were used to characterize the antiviral effects of quercetin. This study utilized network pharmacological analysis, identifying 22 targets associated with BVD-MD. The results of the KEGG pathway showed that quercetin was closely related to Ras and MAPK signaling pathways of BVD-MD. Molecular docking results showed that SRC, NS5B, NOX4 and XDH were the key targets of quercetin in the treatment of BVD-MD. Through network pharmacology, molecular docking and in vitro experiments, quercetin was demonstrated to combat bovine viral diarrhea mucosal disease through key targets of SRC, MAPK1, GSK3B, NS5B and E2. Molecular dynamics analysis showed that quercetin exhibited complex stability with NS5B. This study provides a theoretical and experimental basis for quercetin treatment of BVD-MD and later drug development.
#13 - Straightforward identification of structures of the striatum in bovine and equine forebrains: Guidance to trimming
Abstract in English:
Standardizing trimming the brain for histological diagnosis of neurological diseases is challenging for veterinary pathologists. The striatum is a set of subcortical nuclei of the forebrain, formed by bundles of nerve fibers and gray matter, which consist of the internal and external capsules, caudate, lentiform, and claustrum nuclei. The striatum is related to motricity, which refers to the neural circuits of the extrapyramidal pathways. In domestic animals, the extrapyramidal pathways are of great importance in gait. From the ventral surface of the brain, they are located deep in a strip of the telencephalon corresponding to the olfactory trigone. Bovine and equine brains were routinely formalin-fixed, weighed and measured. Herein, we report a guide for bovine and equine brains’ neuroanatomic trimming and striatum histomorphology. Trimming was performed, and the sections were routinely processed for histology. We used the cross-section rostral to the optic chiasm as the site of choice for histologic sampling to identify the striatum structures. The forebrains were sectioned, and the standard histologic cassette was positioned horizontally or vertically to frame a greater diversity of structures. The histologic slides were labeled with structures of the striatum (caudate nucleus, internal capsule, lentiform nucleus, external capsule and claustrum). Regarding the brain size, handing the cassette orientation over to the forebrain allows the verification to shift the position or collect a second striatum sample for histology.
Abstract in Portuguese:
Padronizar a clivagem do encéfalo para diagnóstico histológico de doenças neurológicas é um desafio para os patologistas veterinários. O corpo estriado é um conjunto de núcleos subcorticais do prosencéfalo, formado por feixes de fibras nervosas e substância cinzenta, que consistem nas cápsulas interna e externa, núcleos caudado, lentiforme e claustro. O corpo estriado está relacionado à motricidade, que se refere aos circuitos neurais das vias extrapiramidais. Nos animais domésticos, as vias extrapiramidais são de grande importância na marcha. Da superfície ventral do cérebro, eles estão localizados profundamente em uma faixa do telencéfalo correspondente ao trígono olfatório. Encéfalos de bovinos e equinos foram rotineiramente fixados em formalina, pesados e medidos. Neste trabalho, relatamos um guia para a clivagem neuroanatômica e histomorfológica do corpo estriado dos cérebros de bovinos e equinos. A clivagem foi realizada e as seções foram processadas rotineiramente para histologia. Utilizamos o corte rostral e tangente ao quiasma óptico como local de escolha para amostragem histológica para identificar as estruturas do corpo estriado. Os prosencéfalos foram seccionados e o cassete histológico padrão foi posicionado horizontal ou verticalmente para enquadrar uma maior diversidade de estruturas. As estruturas do corpo estriado foram identificadas nas lâminas histológicas (núcleo caudado, cápsula interna, núcleo lentiforme, cápsula externa e claustro). Conforme o tamanho do encéfalo, o manuseio do cassete sobre o prosencéfalo permite orientar a necessidade de alterar a posição ou a coleta de uma segunda amostra do corpo estriado para histologia.
#14 - Searching bovine papillomavirus presence in lesions seen on teats of cows
Abstract in English:
The samples were taken from 106 cows with various-looking lesions on their teats and ranged in age from 2 to 8 years. Enzyme-linked immunosorbent assay (ELISA) antigen (Ag) positive for the bovine papillomavirus (BPV) was found in 59 (55.7%) blood serum samples. PCR using FAP59/64 primers was positive for 24 (22.6%) samples. BPV-2 (40, 37.7%), BPV-6 (28, 26.4%), BPV-8 (30, 28.3%), BPV-9 (36, 34%), BPV-10 (32, 30.3%), and BPV-12 (22, 20.8%) were found in a PCR type-specific analysis of single and mixed type teat warts. The highest positivity was observed in BPV-2, BPV-9 and BPV-10 in flat and round forms, BPV-6, BPV-10, BPV-12, and mixed types in rice grain-cauliflower forms, BPV-9 and mixed types in filiform in the distribution of types based on the macroscopic appearance of teat lesions. As for the distribution of BPV types according to age, the most BPV-2 types were found in the age group of two years, the most BPV-10 types in the age group of three years, the most BPV-9 types in the age group of four years, the most BPV-8+BPV-12 types in the age group of five years, and the most mixed types between the ages of six and eight years. The existence of the virus was then checked using electron microscopy on the chosen samples (at least one investigation was conducted), and it was positively identified using BPV type-specific primers. The authors concluded that BPV detection using an ELISA (Ag) test from blood serum samples was shown to be less sensitive than BPV type-specific PCR from wart samples.
Abstract in Portuguese:
The samples were taken from 106 cows with various-looking lesions on their teats and ranged in age from 2 to 8 years. Enzyme-linked immunosorbent assay (ELISA) antigen (Ag) positive for the bovine papillomavirus (BPV) was found in 59 (55.7%) blood serum samples. PCR using FAP59/64 primers was positive for 24 (22.6%) samples. BPV-2 (40, 37.7%), BPV-6 (28, 26.4%), BPV-8 (30, 28.3%), BPV-9 (36, 34%), BPV-10 (32, 30.3%), and BPV-12 (22, 20.8%) were found in a PCR type-specific analysis of single and mixed type teat warts. The highest positivity was observed in BPV-2, BPV-9 and BPV-10 in flat and round forms, BPV-6, BPV-10, BPV-12, and mixed types in rice grain-cauliflower forms, BPV-9 and mixed types in filiform in the distribution of types based on the macroscopic appearance of teat lesions. As for the distribution of BPV types according to age, the most BPV-2 types were found in the age group of two years, the most BPV-10 types in the age group of three years, the most BPV-9 types in the age group of four years, the most BPV-8+BPV-12 types in the age group of five years, and the most mixed types between the ages of six and eight years. The existence of the virus was then checked using electron microscopy on the chosen samples (at least one investigation was conducted), and it was positively identified using BPV type-specific primers. The authors concluded that BPV detection using an ELISA (Ag) test from blood serum samples was shown to be less sensitive than BPV type-specific PCR from wart samples.
#15 - Effects of autolyzed yeast on leukocyte oxidative metabolism and pneumonia occurrence in feedlot steers
Abstract in English:
Although yeast supplementation has shown an immunostimulant effect in feedlot cattle, the question remains whether it influences the occurrence of the bovine respiratory disease complex (BRD) in feedlot cattle. Therefore, our objective was to evaluate whether dietary supplementation with autolyzed yeast affects the efficiency of blood phagocytes, reducing inflammation and the occurrence of BRD in feedlot cattle. A randomized experimental trial was conducted with whole steers with half Angus blood for 106 days: control (n=10): diet without yeast; Y4 (n=12): yeast diet (4g per animal per day); and Y7 (n=7): yeast diet (7g per animal per day). On Days 0, 14, 42, 70, and 105, blood count, leukocyte oxidative metabolism, serum haptoglobin, frequency of nasal secretion and orbital temperature were evaluated. On slaughter day, a lung evaluation was performed. On Days 42 and 70 of feedlot finishing, the treated animals showed increased leukocyte oxidative metabolism (D42 P=0.04; D70 P=0.02) compared to the control group. These animals had a lower frequency of mucopurulent nasal secretion, lower orbital temperature and reduced pneumonia occurrence than the treated groups (P=0.05) with less lung lesion severity (P=0.01), allowing us to infer that the autolyzed yeast improves blood phagocytic function and decreases the inflammation and BRD of feedlot steers, especially at a dose of 4g.
Abstract in Portuguese:
Embora a suplementação com leveduras tenha demonstrado efeito imunoestimulante em bovinos, permanece-se a dúvida se ela influencia na ocorrência do complexo doença respiratória bovina (CDRB) em bovinos confinados. Portanto, objetivou-se avaliar se a suplementação dietética com levedura autolisada influencia a eficiência de fagócitos sanguíneos, reduzindo inflamações e a ocorrência de CDRB em bovinos confinados. Realizou-se um ensaio experimental randomizado com 36 novilhos inteiros 1/2 sangue Angus por 106 dias: controle (n=10): dieta sem levedura; Y4 (n=12): dieta com levedura (4g por animal por dia); e Y7 (n=7): dieta com levedura (7g por animal por dia). Nos dias 0, 14, 42, 70 e 105, hemograma, metabolismo oxidativo de leucócitos, haptoglobina sérica, frequência de secreção nasal e temperatura orbital foram avaliados. No dia do abate, foi realizada avaliação pulmonar. Nos dias 42, e 70 de terminação em confinamento, os animais tratados apresentaram aumento do metabolismo oxidativo dos leucócitos (D42 P=0,04; D70 P=0,02) em relação ao grupo controle. Esses animais apresentaram menor frequência de secreção nasal mucopurulenta, menor temperatura orbital, menor ocorrência de pneumonias (P=0,05) com menor gravidade das lesões pulmonares (P=0,01), permitindo inferir que a levedura autolisada na dieta melhorou a eficiência dos fagócitos sanguíneos, reduzindo inflamações e a ocorrência de CDRB, especialmente na dosagem de 4g.
#16 - Sarcocystis spp. detection in cattle using different diagnostic methods
Abstract in English:
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.
Abstract in Portuguese:
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.
#17 - Malignant epithelioid mesothelioma in senile Red Sindhi cows from Brazil
Abstract in English:
Mesotheliomas in cattle are often described as isolated case reports, and investigations of multiple cases within the same bovine herd are lacking. A series of cases of malignant epithelial mesothelioma, tubulopapilary type, is described in five 15 to 21-year-old Red Sindhi cows from the same herd. Clinical signs included three to eight months of progressive emaciation, dehydration, subcutaneous edema of the lower extremities, and abdominal distension. Grossly, severe subcutaneous edema and hydroperitoneum were noted. Multiple organs’ parietal and visceral serosal surfaces had multifocal to coalescing yellow, firm, sessile nodules ranging from 0.1 to 29.0cm. Similar free nodules floated in the peritoneal fluid. Histologically, the masses comprised a layer of cubic to columnar neoplastic cells forming papillary or cystic proliferation supported by a dense fibrovascular stroma. Neoplastic cells had strong and diffuse cytoplasmic immunolabeling for pan-cytokeratin but were negative for cytokeratin 7 and vimentin. Ultrastructurally, neoplastic cells had delicate microvilli and tight and anchoring junctions. Within the cytoplasm, a moderate amount of loose aggregate of intermediary filament with small mitochondria was observed. Epidemiological investigation evidenced endogamy in this herd. Asbestos exposure was not detected. The diagnosis was based on clinical, gross, histological, and immunohistochemical findings and confirmed by transmission electron microscopy features. A definitive underlying etiology remains unknown.
Abstract in Portuguese:
Mesotelioma em bovinos são frequentemente relatados como casos isolados, descrições de múltiplos casos no mesmo rebanho bovino não foram encontrados. Descreve-se uma série de casos de mesotelioma epitelial maligno, tipo tubulopapilar, em cinco vacas Red Sindi de 15 a 21 anos de idade do mesmo rebanho. Os sinais clínicos incluíram emagrecimento progressivo, desidratação, edema subcutâneo das extremidades dos membros e distensão abdominal em um curso clínico que variou de três a oito meses. Macroscopicamente, observou-se edema subcutâneo acentuado e hidroperitônio. Nas serosas parietais e viscerais de múltiplos órgãos haviam nódulos multifocais a coalescentes amarelo-claros, firmes e sésseis que variavam de 0,1 a 29,0 centímetros de diâmetro. Nódulos livres semelhantes também flutuavam no líquido peritoneal. Histologicamente, as massas eram compostas por uma camada de células cúbicas a colunares formando proliferação papilar ou cística sustentada por estroma fibrovascular denso. As células neoplásicas apresentavam imunomarcação citoplasmática forte e difusa para pan-citoqueratina, mas eram negativas para citoqueratina 7 e vimentina. Ultraestruturalmente, as células neoplásicas apresentavam delicadas microvilosidades e junções comunicantes e de ancoragem. No citoplasma observou-se moderada quantidade de agregados de filamentos intermediários soltos e pequenas mitocôndrias. A investigação epidemiológica revelou que não houve inserção de bovinos de outros rebanhos por mais de 30 anos e evidenciou endogamia. Não foram encontradas possíveis fontes de amianto para os bovinos deste rebanho. O diagnóstico de mesotelioma foi baseado em características clínicas, macroscópicas, histológicas, imuno-histoquímicas e confirmado pelos achados de microscopia eletrônica. A etiologia permanece desconhecida.
#18 - Bovine genital leptospirosis: Findings in bulls maintained in Caatinga biome conditions
Abstract in English:
Leptospirosis is a disease that causes economic and social impact, as it affects wild and domestic animals and humans. There may be peculiarities in the epidemiology of this disease in the Caatinga biome, Brazil, where the environment is adverse and the etiologic agent, Leptospira spp., requires alternative transmission routes. Considering that in bovine leptospirosis the genital carrier is constantly neglected and the lack of reports on the role of bulls in the epidemiology of the bovine genital leptospirosis (BGL) syndrome, mainly in semiarid conditions such as Caatinga biome, this study aimed to investigate bulls maintained in Caatinga biome conditions as genital carriers of leptospires. Urinary tract (urine, bladder, and kidney) and reproductive tract (vas deferens, cauda epididymis, and vesicular gland) samples were collected from 42 slaughtered bulls. Microscopic agglutination test (MAT), polymerase chain reaction (PCR), and microbiological isolation were included as diagnostic methods. Anti-Leptospira spp. antibodies were found in 17 (40.48%) animals, while 26 animals (61.90%) had at least one organ or urine with leptospiral DNA, and 10 animals (23.81%) were positive at bacteriological culture. Sequenced samples targeting the LipL32 gene showed 99% similarity with Leptospira borgpetersenii. Molecular analysis of samples from the vas deferens and cauda epididymis is recommended for the diagnosis of genital leptospirosis in bulls and, if it is impossible to collect these tissues, semen can be used. In conclusion, this study provides important information relating to bulls from the Caatinga biome, Brazil, as carriers of genital leptospirosis. The results indicate that, even under adverse environmental conditions, leptospires may survive and propagate, mainly due to the characteristic of genital carriers for the sexually spreading of adapted Leptospira species without influence by external variables. Thus, prevention and control strategies for bovine leptospirosis need to include actions aimed at the genital carrier.
Abstract in Portuguese:
A leptospirose é uma doença que causa impacto econômico e social, pois afeta animais silvestres, domésticos e humanos. É possível que existam peculiaridades na epidemiologia desta doença no bioma Caatinga, Brasil, onde o ambiente é adverso e o agente etiológico, Leptospira spp., requer vias alternativas de transmissão. Considerando que na leptospirose bovina o portador genital é constantemente negligenciado e a falta de relatos sobre o papel dos touros na epidemiologia da síndrome da leptospirose genital bovina (BGL), principalmente em condições semiáridas como no bioma Caatinga, este estudo teve como objetivo investigar touros mantidos em condições do bioma Caatinga como portadores genitais de leptospiras. Amostras do trato urinário (urina, bexiga e rim) e do trato reprodutivo (ducto deferente, cauda do epidídimo e glândula vesicular) foram coletadas de 42 touros abatidos. Teste de soroaglutinação microscópica (SAM), reação em cadeia da polimerase (PCR) e isolamento microbiológico foram incluídos como métodos de diagnóstico. Anticorpos anti-Leptospira spp. foram encontrados em 17 (40,48%) animais, enquanto 26 animais (61,90%) apresentaram pelo menos um órgão ou urina com DNA leptospírico, e 10 animais (23,81%) foram positivos na cultura bacteriológica. As amostras sequenciadas a partir do gene LipL32 apresentaram 99% de similaridade com Leptospira borgpetersenii. Recomenda-se a análise molecular de amostras de ducto deferente e cauda do epidídimo para o diagnóstico de leptospirose genital em touros e, na impossibilidade da coleta desses tecidos, o sêmen pode ser utilizado. Em conclusão, este estudo fornece informações importantes sobre touros do bioma Caatinga, Brasil, como portadores de leptospirose genital. Os resultados indicam que, mesmo em condições ambientais adversas, as leptospiras podem sobreviver e se propagar, principalmente devido à característica de os portadores genitais disseminarem sexualmente espécies adaptadas de Leptospira sem influência de variáveis externas. Assim, as estratégias de prevenção e controle da leptospirose bovina precisam incluir ações voltadas para o portador genital.
#19 - Retrospective study of poxviruses diagnosed in cattle from Goiás State, Brazil (2010-2018)
Abstract in English:
A retrospective study of poxvirus infections diagnosed in cattle from Goiás state (GO), Brazil, from 2010 to 2018, was performed. All cases have been investigated by the GO Official Veterinary Service (Agrodefesa), from which technical forms and protocols of veterinary diagnosis laboratories were reviewed. In most cases, samples of oral or cutaneous tissues and/or swabs were submitted for virological diagnosis by polymerase chain reaction (PCR) and/or virus isolation. Thirty seven outbreaks/cases of vesicular disease were notified in cattle of 25 counties; in 33 cases the animals presented lesions clinically compatible with poxviruses. The etiology of 25 out of 33 outbreaks/cases was confirmed as poxviruses by PCR and/or viral isolation: 13 as bovine vaccinia virus (VACV), six as pseudocowpox virus (PCPV), five as bovine papular stomatitis virus (BPSV) and one coinfection (VACV and an Orf virus-like parapoxvirus). The laboratory confirmed that cases occurred mainly in dairy cattle (19/25) and during the dry season (22/25). In adult cattle, gross changes were observed mainly in the teats and udder and included vesicles, ulcers, crusts, papules and scars and varied of type, severity and affected region, depending on the poxvirus species. In calves, the main lesions were ulcers in the mouth and muzzle. Zoonotic lesions compatible with poxvirus infections were observed for all diagnosed poxviruses, affecting especially the hands of milkers and other farm workers. Our data demonstrate the sanitary and economic relevance of these diseases and the wide circulation of different poxviruses in cattle from GO.
Abstract in Portuguese:
Foi realizado um estudo retrospectivo das infecções por poxvírus diagnosticadas em bovinos do estado de Goiás (GO), entre 2010 e 2018. Todos os casos foram investigados pela Agência Goiana de Defesa Agropecuária (Agrodefesa). Foram revisados formulários técnicos e protocolos de laboratórios de diagnóstico veterinário. Na maioria dos casos, amostras de tecidos orais ou cutâneos e/ou swabs foram encaminhadas para diagnóstico virológico. Foram notificados 37 surtos/casos de doença vesicular em bovinos em 25 municípios; em 33 casos os animais apresentavam lesões clinicamente compatíveis com poxvírus. A etiologia de 25 de 33 surtos/casos foi confirmada como poxvírus por PCR e/ou isolamento viral: 13 como vírus vaccínia (VACV), seis como vírus pseudocowpox (PCPV), cinco como vírus da estomatite papular bovina (BPSV) e um caso de coinfecção (VACV e um parapoxvírus semelhante ao Orf vírus). Os casos confirmados laboratorialmente ocorreram principalmente em bovinos leiteiros (19/25) e durante a estação seca (22/25). Em bovinos adultos, alterações macroscópicas foram observadas principalmente nas tetas e úbere e incluíram vesículas, úlceras, crostas, pápulas e cicatrizes e variaram quanto ao tipo, gravidade e região afetada, dependendo da espécie do poxvírus. Em bezerros, as principais lesões foram úlceras na boca e focinho. Lesões zoonóticas compatíveis com infecção por poxvírus foram observadas em todas as poxviroses diagnosticadas, afetando principalmente as mãos dos ordenhadores e outros trabalhadores rurais. Nossos dados demonstram a relevância sanitária e econômica dessas doenças e a ampla circulação de diferentes poxvírus em bovinos de GO.
#20 - Indirect ELISA as a complementary diagnostic method of bovine tuberculosis
Abstract in English:
Bovine tuberculosis is an economic and health problem, requiring precise diagnostic methods for its control and eradication. The aim of this study was to evaluate the performance of a commercial enzyme-linked immunosorbent assay (ELISA) test for the diagnosis of bovine tuberculosis. A total of 1,644 cattle from eight dairy herds were evaluated using the comparative cervical tuberculin test (CCTT). Three of the herds had no recent tuberculosis infection, and the other five had shown positive results in a previous tuberculin test. For the serological diagnosis of tuberculosis, a commercial ELISA antibody test kit for Mycobacterium bovis was used. Serum samples from 846 cattle from the eight herds were evaluated using ELISA for M. bovis. Animals that were positive based on either CCTT or ELISA for M. bovis or both were sent to slaughter. Samples of their lungs, livers, and lymph nodes were collected and stored under refrigeration for microbiological culture and subsequent confirmation by polymerase chain reaction. Samples from the same tissues were also fixed with 10% formaldehyde in bottles for histopathological examination and stained with hematoxylin and eosin (HE). Of the 1,644 cattle, 61 were considered positive and 65 inconclusive based on CCTT. Retesting of the inconclusive samples identified an additional 19 positive cases, totaling 80 (4.8%) CCTT-positive animals from five herds. ELISA for M. bovis identified 4.2% (36/846) positive cattle, of which 35 were considered negative and one inconclusive based on CCTT. Of the 36 positive cases identified by ELISA for M. bovis, 27 were euthanized, 11% (3/27) showed suggestive lesions of tuberculosis on macroscopic examination, and two were confirmed by histological, microbiological, and PCR methods. The weak association of ELISA for M. bovis with the results obtained by macroscopic, histological, and microbiological isolation indicates the fragility of ELISA performance in field conditions. Therefore, it is suggested that its use as a complementary method for herd sanitation be based on the local epidemiological situation.
Abstract in Portuguese:
A tuberculose bovina é um problema econômico mundial e de saúde, que requer métodos de diagnóstico precisos para controle e erradicação. Objetivou-se com este estudo avaliar o desempenho de um teste comercial de ELISA no diagnóstico da tuberculose bovina. Foram avaliados pelo teste cervical comparativo (TCC) 1644 bovinos, provenientes de oito rebanhos de exploração leiteira, sendo três deles sem histórico recente da doença, e outros cinco com resultados positivos no último exame de tuberculinização. Para o diagnóstico sorológico da tuberculose utilizou-se um kit comercial de ELISA Mycobacterium bovis antibody test (ELISA M. bovis). Amostras de soro sanguíneo de 846 bovinos provenientes dos mesmos rebanhos foram também avaliadas no ELISA M. bovis. Os bovinos positivos no TCC e/ou ELISA M. bovis foram encaminhados para o abate sanitário. Dos positivos no ELISA para M. bovis foi realizado o exame macroscópico das carcaças e classificação das mesmas em: com presença ou ausência de lesões. Amostras de pulmão, fígado, e linfonodos, foram colhidas em duplicata para realização dos exames de cultivo microbiológico com posterior confirmação por PCR, e exame histopatológico com coloração de hematoxilina e eosina (HE). Dos 1,644 bovinos, 61 foram considerados positivos e 65 inconclusivos no TCC. O reteste dos inconclusivos identificou mais 19 positivos. No total, 80 (4,8%) bovinos positivos no TCC, provenientes de 5 rebanhos foram encaminhados para abate. O ELISA para M. bovis identificou 4,2% (36/846) de bovinos positivos, sendo 36 considerados negativos e um inconclusivo no exame de tuberculinização. Dos positivos no ELISA para M. bovis, 27 foram eutanasiados, e no exame macroscópico das carcaças 11% (3/27) dos animais apresentaram lesões sugestivas de tuberculose, e em apenas dois houve confirmação da doença pelos métodos histológico, microbiológico e PCR. A baixa associação dos resultados obtidos no ELISA para M. bovis com os exames macroscópico, histológico e isolamento microbiológico apontam para a fragilidade do desempenho do ELISA para o diagnóstico de tuberculose. Sugere-se assim que seu uso como método complementar para saneamento de rebanhos, seja adotado com cautela e considere a situação epidemiológica local.
