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1.
Sensors (Basel) ; 21(4)2021 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-33671216

RESUMO

The prediction of health disorders is the goal of many sensor systems in dairy farming. Although mastitis and lameness are the most common health disorders in dairy cows, these diseases or treatments are a rare event related to a single day and cow. A number of studies already developed and evaluated models for classifying cows in need of treatment for mastitis and lameness with machine learning methods, but few have illustrated the effects of the positive predictive value (PPV) on practical application. The objective of this study was to investigate the importance of low-frequency treatments of mastitis or lameness for the applicability of these classification models in practice. Data from three German dairy farms contained animal individual sensor data (milkings, activity, feed intake) and were classified using machine learning models developed in a previous study. Subsequently, different risk criteria (previous treatments, information from milk recording, early lactation) were designed to isolate high-risk groups. Restricting selection to cows with previous mastitis or hoof treatment achieved the highest increase in PPV from 0.07 to 0.20 and 0.15, respectively. However, the known low daily risk of a treatment per cow remains the critical factor that prevents the reduction of daily false-positive alarms to a satisfactory level. Sensor systems should be seen as additional decision-support aid to the farmers' expert knowledge.


Assuntos
Criação de Animais Domésticos/instrumentação , Doenças dos Bovinos/diagnóstico , Indústria de Laticínios , Coxeadura Animal/diagnóstico , Mastite/diagnóstico , Animais , Bovinos , Fazendas , Feminino , Lactação , Leite
2.
Methods Mol Biol ; 2291: 19-86, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33704748

RESUMO

Cattle and other ruminants are primary reservoirs for Shiga toxin-producing Escherichia coli (STEC) strains which have a highly variable, but unpredictable, pathogenic potential for humans. Domestic swine can carry and shed STEC, but only STEC strains producing the Shiga toxin (Stx) 2e variant and causing edema disease in piglets are considered pathogens of veterinary medical interest. In this chapter, we present general diagnostic workflows for sampling livestock animals to assess STEC prevalence, magnitude, and duration of host colonization. This is followed by detailed method protocols for STEC detection and typing at genetic and phenotypic levels to assess the relative virulence exerted by the strains.


Assuntos
Doenças dos Bovinos , Infecções por Escherichia coli , Toxina Shiga II/metabolismo , Escherichia coli Shiga Toxigênica , Doenças dos Suínos , Animais , Bovinos , Doenças dos Bovinos/diagnóstico , Doenças dos Bovinos/metabolismo , Doenças dos Bovinos/microbiologia , Infecções por Escherichia coli/diagnóstico , Infecções por Escherichia coli/metabolismo , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/veterinária , Escherichia coli Shiga Toxigênica/classificação , Escherichia coli Shiga Toxigênica/isolamento & purificação , Escherichia coli Shiga Toxigênica/metabolismo , Escherichia coli Shiga Toxigênica/patogenicidade , Suínos , Doenças dos Suínos/diagnóstico , Doenças dos Suínos/metabolismo , Doenças dos Suínos/microbiologia
3.
Schweiz Arch Tierheilkd ; 163(2): 139-152, 2021 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-33528364

RESUMO

INTRODUCTION: Herd medicine is a field of buiatrics characterized by regular and systematic visits by the veterinarian to improve the health and performance of the animals, the quality of animal products and finally the satisfaction of the farm staff. Internationally established key indicators, such as age at first calving, heat recognition rate or the percentage of cows with clinical mastitis per month (%),26 have been available for a long time in the areas of fertility and udder health. These key indicators help veterinarians to recognize and define health problems at herd level at an early stage and to work out measures for their improvement. Such key indicators are currently lacking in the field of claw health, hence making standardized identification of problem farms considerably more difficult. Considering the permanent negative influence of claw health problems on fertility, performance and overall animal welfare, it becomes clear how valuable claw health indicators will be in the future. The aim of this study was, therefore, to develop both primary and secondary indicators of claw health and to define corresponding limit values for Switzerland. Based on a literature search, several primary and secondary indicators were developed (1˚K: Herd problem Yes/No, 2˚K: Classification of the problem). These were discussed in an expert panel consisting of practicing veterinarians, staff of the Swiss bovine herd health service and university professors with regard to their possible practical implementation and relevance. Finally, 3 primary and 10 secondary indicators were judged to be suitable to assess a herd with regard to claw health. The primary key indicators were: proportion of cows leaving the herd due to a claw problem, proportion of lame cows of a herd, and proportion of cattle with at least one claw disease. The corresponding provisional limit values (exceeding the value = problem) for Switzerland were worked out by means of surveys among farmers, hoof trimmers, veterinary students and veterinarians. In addition, recommendations from the literature and current prevalence studies were used to adapt the defined limit values to the situation on Swiss farms. In the coming years, the claw health project «Gesunde Klauen - das Fundament für die Zukunft¼ will collect current prevalence values of claw diseases, and the limit values will then be adjusted and specified accordingly.


Assuntos
Doenças dos Bovinos/diagnóstico , Indústria de Laticínios/métodos , Doenças do Pé/veterinária , Casco e Garras/patologia , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças do Pé/diagnóstico , Doenças do Pé/epidemiologia , Prevalência , Suíça
4.
J Parasitol ; 106(6): 772-788, 2020 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-33326588

RESUMO

Toxoplasma gondii infections are common in humans and animals worldwide. The ingestion of food or water contaminated with oocysts excreted by infected cats or ingesting uncooked or undercooked meat containing tissue cysts of T. gondii are the 2 major modes of transmission of T. gondii. Viable T. gondii is more prevalent in pork and lamb than in beef. In the past decade, there have been many articles on the high seroprevalence in cattle, particularly from China. There is a report of an outbreak of acute toxoplasmosis in humans suspected to be linked to the ingestion of Artisan fresh cheese from cow's milk. There are conflicting reports concerning the rate of congenital transmission of T. gondii in cattle, especially from Brazil. In a report from Brazil, viable T. gondii was isolated from the blood of 1 of 60 pregnant cows slaughtered at an abattoir and from 1 fetus. The role of beef in the epidemiology of T. gondii infections is still not clear. Here, we review prevalence, persistence of infection, clinical disease, epidemiology, and public health risks of T. gondii infections in cattle from beef and cow's milk worldwide for the past decade.


Assuntos
Doenças dos Bovinos/parasitologia , Saúde Pública , Toxoplasmose Animal/parasitologia , Animais , Anticorpos Antiprotozoários/sangue , Brasil/epidemiologia , Bovinos , Doenças dos Bovinos/diagnóstico , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/transmissão , Variação Genética , Genótipo , Saúde Global , Humanos , Carne/parasitologia , Leite/parasitologia , Estudos Soroepidemiológicos , Toxoplasma/classificação , Toxoplasma/genética , Toxoplasma/imunologia , Toxoplasmose Animal/diagnóstico , Toxoplasmose Animal/epidemiologia , Toxoplasmose Animal/transmissão , Toxoplasmose Congênita/transmissão
5.
PLoS One ; 15(9): e0236336, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32881863

RESUMO

Bovine paratuberculosis (PTB) is a chronic granulomatous enteritis, caused by Mycobacterium avium subsp. paratuberculosis (MAP), responsible for important economic losses in the dairy industry. Current diagnostic methods have low sensitivities for detection of latent forms of MAP infection, defined by focal granulomatous lesions and scarce humoral response or MAP presence. In contrast, patent infections correspond to multifocal and diffuse types of enteritis where there is increased antibody production, and substantial mycobacterial load. Our previous RNA-Seq analysis allowed the selection of five candidate biomarkers overexpressed in peripheral blood of MAP infected Holstein cows with focal (ABCA13 and MMP8) and diffuse (FAM84A, SPARC and DES) lesions vs. control animals with no detectable PTB-associated lesions in intestine and regional lymph nodes. The aim of the current study was to assess the PTB diagnostic potential of commercial ELISAs designed for the specific detection of these biomarkers. The ability of these ELISAs to identify animals with latent and/or patent forms of MAP infection was investigated using serum from naturally infected cattle (n = 88) and non-infected control animals (n = 67). ROC analysis revealed that the ABCA13-based ELISA showed the highest diagnostic accuracy for the detection of infected animals with focal lesions (AUC 0.837, sensitivity 79.25% and specificity 88.06%) and with any type of histological lesion (AUC 0.793, sensitivity 69.41% and specificity 86.57%) improving on the diagnostic performance of the popular IDEXX ELISA and other conventional diagnostic methods. SPARC and MMP8 showed the highest diagnostic accuracy for the detection of animals with multifocal (AUC 0.852) and diffuse lesions (AUC 0.831), respectively. In conclusion, our results suggest that quantification of ABCA13, SPARC and MMP8 by ELISA has the potential for implementation as a diagnostic tool to reliably identify MAP infection, greatly improving early detection of MAP latent infections when antibody responses and fecal shedding are undetectable using conventional diagnostic methods.


Assuntos
Doenças dos Bovinos/diagnóstico , Bovinos/microbiologia , Mycobacterium avium subsp. paratuberculosis/isolamento & purificação , Paratuberculose/diagnóstico , Animais , Biomarcadores/análise , Doenças dos Bovinos/patologia , Ensaio de Imunoadsorção Enzimática , Fezes/microbiologia , Feminino , Paratuberculose/patologia , Curva ROC
6.
Toxicon ; 187: 122-128, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32891666

RESUMO

Direct analysis in real time (DART) coupled to high-resolution mass spectrometry (HRMS) was applied for the first time to veterinary forensic toxicology to investigate the presence of toxic compounds in hay after an episode of acute intoxication in a dairy cattle farm. In addition to gross field necropsy and histological examination, microbial cultures, and heavy metals analysis, the molecular fingerprinting of the suspected hay batch was investigated by DART-HRMS. DART-HRMS revealed a distinct signal of m/z 507.2289 in the hay batch thought to be associated with the digestive complications. A search on chemical structure databases matched the ion with asperphenamate, a toxin produced by Penicillium spp. and Aspergillus spp. Liquid Chromatography-HMRS analysis and electrospray-HRMS-MS/MS of the hay extracts further characterized the structure and confirmed the identification of the compound as asperphenamate. Asperphenamate is fungal metabolite which can have cytotoxic and antitumor activity in humans, and it is classified as acute toxicant and harmful if swallowed.


Assuntos
Doenças dos Bovinos/diagnóstico , Constipação Intestinal/veterinária , Fenilalanina/análogos & derivados , Animais , Aspergillus , Bovinos , Constipação Intestinal/complicações , Constipação Intestinal/diagnóstico , Toxicologia Forense , Fenilalanina/análise , Espectrometria de Massas em Tandem
7.
Vet Clin North Am Food Anim Pract ; 36(3): 641-652, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32948411

RESUMO

Ionophores are a commonly used feed additive for animals and when used properly are safe. When feed mis-mixing occurs and an elevated dose of ionophore is given, a toxicosis can develop. Myocardial and skeletal muscles are the targets of a toxicosis. In many species there is a delay from the time of ingestion of a toxic dose in feed to when clinical signs occur. This makes it difficult to collect the feed in question that was at an elevated concentration. Cardiac troponins in serum can be used to make a diagnosis of an ionophore toxicosis.


Assuntos
Doenças dos Bovinos/induzido quimicamente , Ionóforos/administração & dosagem , Ionóforos/envenenamento , Ração Animal/efeitos adversos , Ração Animal/análise , Animais , Bovinos , Doenças dos Bovinos/diagnóstico , Doenças dos Bovinos/metabolismo
8.
J S Afr Vet Assoc ; 91(0): e1-e5, 2020 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-32787426

RESUMO

A 3-year-old, pregnant, Alpine Brown cow showed a rapidly growing, pedunculated, skin mass located at the umbilical region, reaching 8 kg in weight over a 3-month period after its initial detection. Six days after parturition, the mass was completely surgically excised. During the follow-up period, the cow remained in good health, without signs of recurrence, and showed increased milk production. Histological examination of the mass revealed a loose proliferation of spindle-shaped or stellate cells, immersed in an abundant myxoid matrix with admixed numerous thin-walled blood vessels. Immunohistochemically, the tumour cells were positive for vimentin, α-smooth muscle actin, and desmin. Gross and histopathological features were compatible with superficial angiomyxoma, a subtype of angiomyxoma rarely described in humans, but not in the veterinary literature. The tumour did not infiltrate into the surrounding tissues, and there was no post-excision recurrence after 3 months. The possibility of hormonal dependence of the tumour during pregnancy is discussed based on such findings in some human cases.


Assuntos
Doenças dos Bovinos/diagnóstico , Mixoma/veterinária , Neoplasias Cutâneas/veterinária , Animais , Bovinos , Doenças dos Bovinos/etiologia , Doenças dos Bovinos/cirurgia , Feminino , Mixoma/diagnóstico , Mixoma/etiologia , Mixoma/cirurgia , Gravidez , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/etiologia , Neoplasias Cutâneas/cirurgia
9.
Vet J ; 262: 105516, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32792096

RESUMO

Endometrial cytobrush cytology has been recommended as a reliable method for determining the percentage of polymorphonuclear leukocytes (PMN%) in cattle smears to diagnose cytological endometritis (CE). In this study, the clarity of cytobrush cytological smears and the influence of different sample evaluation methods (number and types of cells counted) on CE diagnosis were evaluated. Samples from 28 lactating Holstein cows were collected weekly between 3 and 7 weeks postpartum. Smear clarity, based on cell density, quality of cell morphology, and red blood cell contamination, was significantly poorer at 3 weeks than between 5 and 7 weeks postpartum. Five different cell counting methods (C100, C200, C300, C400, and C500) were used, where 100-500 nucleated cells (endometrial epithelial cells, PMN consisting of neutrophils, eosinophils and basophils, lymphocytes, and macrophages) were counted. Agreement of diagnostic results for CE between C300 and C500 and between C400 and C500 was excellent at all observation times. In calculations of the PMN% based on whether the number of lymphocytes and macrophages were or were not excluded in the denominator, exclusion of these cells in the calculations did not affect the diagnosis of CE. While reduced clarity in earlier stage samples might interfere with the accuracy of cytobrush cytology, C300 can be recommended to determine the endometrial PMN%.


Assuntos
Doenças dos Bovinos/diagnóstico , Citodiagnóstico/veterinária , Endometrite/veterinária , Endométrio/citologia , Granulócitos/citologia , Período Pós-Parto , Animais , Bovinos , Citodiagnóstico/métodos , Endometrite/diagnóstico , Endométrio/patologia , Feminino , Contagem de Leucócitos/veterinária
10.
Anim Sci J ; 91(1): e13442, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32851739

RESUMO

Predicting periparturient disease risk is of immense value to the dairy industry. Periparturient diseases are interrelated with each other; however, predicting the onset risk of these diseases has predominantly been based on a single blood parameter for a single disease. This study examined a new diagnostic method to predict the risk of periparturient diseases. We conducted cluster analysis of multiple blood constituents from 20 Holstein cattle at 1 week post-partum, and the cattle were divided into two groups, A or B. We then compared the periparturient and early-lactation blood constituents of these groups. Group B had significantly higher 3-hydroxybutyric acid concentrations and were suspected to have subclinical ketosis. Group B also had significantly lower calcium concentrations, with a tendency for subclinical hypocalcemia. We also performed discriminant analysis using blood parameters at 1 week post-partum, which grouped the population into the same two groups as the cluster analysis based on three variables: inorganic phosphorus, calcium, and either phospholipids or total cholesterol. We further showed that these discriminant functions could be used to predict the risk of periparturient disease even before parturition. Our results indicate that cluster analysis with multiple blood constituents is useful for predicting periparturient disease risks.


Assuntos
Ácido 3-Hidroxibutírico/sangue , Cálcio/sangue , Doenças dos Bovinos/diagnóstico , Análise por Conglomerados , Hipocalcemia/diagnóstico , Hipocalcemia/veterinária , Cetose/diagnóstico , Cetose/veterinária , Parto , Animais , Biomarcadores/sangue , Bovinos , Feminino , Lactação , Período Pós-Parto , Valor Preditivo dos Testes , Risco
11.
Trop Anim Health Prod ; 52(6): 2809-2816, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32681447

RESUMO

Bovine coronaviruses are spread all over the world. They cause two types of clinical manifestations in cattle either an enteric, calf diarrhoea and winter dysentery in adult cattle, or respiratory in all age groups of cattle. The role of coronaviruses in respiratory infections is still a hot topic of discussion since they have been isolated from sick as well as healthy animals and replication of disease is rarely successful. Bovine coronavirus infection is characterised by high morbidity but low mortality. The laboratory diagnosis is typically based on serological or molecular methods. There is no registered drug for the treatment of virus infections in cattle and we are limited to supportive therapy and preventative measures. The prevention of infection is based on vaccination, biosecurity, management and hygiene. This paper will cover epidemiology, taxonomy, pathogenesis, clinical signs, diagnosis, therapy, economic impact and prevention of coronavirus infections in cattle.


Assuntos
Doenças dos Bovinos/virologia , Infecções por Coronavirus/veterinária , Coronavirus Bovino , Animais , Bovinos , Doenças dos Bovinos/diagnóstico , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/terapia , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/terapia , Coronavirus Bovino/classificação , Coronavirus Bovino/isolamento & purificação , Coronavirus Bovino/fisiologia , Diarreia/veterinária , Diarreia/virologia , Enterocolite Necrosante/veterinária , Enterocolite Necrosante/virologia , Infecções Respiratórias/veterinária , Infecções Respiratórias/virologia , Vacinação/veterinária
12.
Proc Natl Acad Sci U S A ; 117(31): 18302-18309, 2020 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-32690677

RESUMO

The ability to evaluate sperm at the microscopic level, at high-throughput, would be useful for assisted reproductive technologies (ARTs), as it can allow specific selection of sperm cells for in vitro fertilization (IVF). The tradeoff between intrinsic imaging and external contrast agents is particularly acute in reproductive medicine. The use of fluorescence labels has enabled new cell-sorting strategies and given new insights into developmental biology. Nevertheless, using extrinsic contrast agents is often too invasive for routine clinical operation. Raising questions about cell viability, especially for single-cell selection, clinicians prefer intrinsic contrast in the form of phase-contrast, differential-interference contrast, or Hoffman modulation contrast. While such instruments are nondestructive, the resulting image suffers from a lack of specificity. In this work, we provide a template to circumvent the tradeoff between cell viability and specificity by combining high-sensitivity phase imaging with deep learning. In order to introduce specificity to label-free images, we trained a deep-convolutional neural network to perform semantic segmentation on quantitative phase maps. This approach, a form of phase imaging with computational specificity (PICS), allowed us to efficiently analyze thousands of sperm cells and identify correlations between dry-mass content and artificial-reproduction outcomes. Specifically, we found that the dry-mass content ratios between the head, midpiece, and tail of the cells can predict the percentages of success for zygote cleavage and embryo blastocyst formation.


Assuntos
Doenças dos Bovinos/diagnóstico , Processamento de Imagem Assistida por Computador/métodos , Infertilidade Masculina/veterinária , Redes Neurais de Computação , Espermatozoides/ultraestrutura , Animais , Bovinos , Feminino , Infertilidade Masculina/diagnóstico , Masculino , Folículo Ovariano , Óvulo/fisiologia , Análise do Sêmen
13.
Acta Vet Scand ; 62(1): 29, 2020 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-32532360

RESUMO

BACKGROUND: Ultrasonographic documentation of perforated abomasal ulcer has not been published till now. This report describes the clinical, ultrasonographic and postmortem findings in a Jersey cow with type-3 abomasal ulcer and left displacement of the abomasum (LDA). CASE REPORT: The main clinical findings were abnormal demeanour, rumen atony and tympany, positive foreign body tests, positive auscultation and simultaneous ballottement on the left side, abdominal guarding and loss of negative pressure in the abdominal cavity. The tentative diagnosis was peritonitis and LDA. Abdominal ultrasonography produced images typical of LDA, and in one location between the abdominal wall and abomasum there was a layer of fibrin, a fibrin clot, a break in the abomasal contour, suggestive of a perforated ulcer, and partial obstruction of this gap with fibrin. The diagnosis of perforated abomasal ulcer with subsequent peritonitis was confirmed during postmortem examination. CONCLUSIONS: The examination of this case shows that under certain circumstances, ultrasonographic imaging of a perforated abomasal ulcer in a cow is possible. Antemortem diagnosis of type-3 abomasal ulcer is preferable to relying on exploratory laparotomy and/or post-mortem examination.


Assuntos
Abomaso/diagnóstico por imagem , Doenças dos Bovinos/diagnóstico , Peritonite/veterinária , Úlcera Gástrica/veterinária , Abomaso/patologia , Animais , Bovinos , Doenças dos Bovinos/diagnóstico por imagem , Feminino , Peritonite/diagnóstico , Peritonite/diagnóstico por imagem , Úlcera Gástrica/diagnóstico , Úlcera Gástrica/diagnóstico por imagem , Ultrassonografia/veterinária
14.
PLoS One ; 15(6): e0234360, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32520958

RESUMO

Coxiella burnetii causes Q fever in humans and coxiellosis in animals. In humans, it causes acute febrile illnesses like influenza, pneumonia, hepatitis, and chronic illnesses such as endocarditis, vascular infection, and post-infectious fatigue syndrome. It is widely distributed worldwide, and its main reservoirs are sheep, goats, and cattle. This study aimed to determine the frequency of C. burnetii infection using molecular detection and to identify the associated factors in livestock farmers and cattle from the Magdalena Medio region of Antioquia, Colombia. Using real-time polymerase chain reaction (PCR), molecular detection was performed for the IS1111 insertion sequence of C. burnetii using genomic DNA collected from the peripheral blood of 143 livestock farmers and 192 cattle from 24 farms located in Puerto Berrío, Puerto Nare, and Puerto Triunfo. To confirm the results, bidirectional amplicon sequencing of 16S rRNA was performed in four of the positive samples. Additionally, factors associated with C. burnetii were identified using a Poisson regression with cluster effect adjustment. Real-time PCR showed positive results in 25.9% and 19.5% of livestock farmer samples and cattle samples, respectively. For livestock farmers, factors associated with C. burnetii were the area where the farm was located [Puerto Berrío, adjusted prevalence ratio (aPR): 2.13, 95% confidence interval (CI): 1.10-4.11], presence of hens (aPR: 1.47, 95% CI: 1.21-1.79), horses (aPR: 1.61, 95% CI: 1.54-1.67), and ticks (aPR: 2.36, 95% CI: 1.03-5.42) in the residence, and consumption of raw milk (aPR: 1.47, 95% CI: 1.26-1.72). For cattle, the factors associated with Coxiella genus were municipality (Puerto Nare; aPR: 0.39, 95% CI: 0.37-0.41) and time of residence on the farm (≥49 months; aPR: 2.28, 95% CI: 1.03-5.20). By analyzing sequences of the 16S rRNA molecular marker, C. burnetii infection was confirmed in livestock farmers. However, in cattle, only the presence of Coxiella-type bacteria was identified. Further research is necessary to determine the potential role that these types of bacteria have as etiological agents for disease in livestock farmers and cattle from the study area.


Assuntos
Coxiella burnetii/genética , Coxiella burnetii/isolamento & purificação , Febre Q/diagnóstico , Adulto , Animais , Anticorpos Antibacterianos/sangue , Bovinos , Doenças dos Bovinos/diagnóstico , Doenças dos Bovinos/microbiologia , Colômbia/epidemiologia , Coxiella burnetii/patogenicidade , DNA Bacteriano/genética , Fazendeiros , Feminino , Humanos , Gado/genética , Masculino , Pessoa de Meia-Idade , Prevalência , Febre Q/sangue , Febre Q/epidemiologia , RNA Ribossômico 16S/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos , Zoonoses/diagnóstico , Zoonoses/genética
15.
PLoS One ; 15(6): e0233695, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32479551

RESUMO

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


Assuntos
Doenças dos Bovinos/sangue , Mycobacterium avium/imunologia , Paratuberculose/sangue , Testes Sorológicos/veterinária , Doenças dos Ovinos/sangue , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/imunologia , Bovinos , Doenças dos Bovinos/diagnóstico , Doenças dos Bovinos/microbiologia , Ensaio de Imunoadsorção Enzimática/métodos , Ensaio de Imunoadsorção Enzimática/veterinária , Cabras , Mycobacterium avium/patogenicidade , Paratuberculose/diagnóstico , Paratuberculose/microbiologia , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Testes Sorológicos/métodos , Ovinos , Doenças dos Ovinos/diagnóstico , Doenças dos Ovinos/microbiologia
16.
Res Vet Sci ; 131: 259-265, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32442726

RESUMO

Measuring core body temperature is used as part of the diagnostic process in assessing the health of animals. Typically in calves, this is carried out using a rectal thermometer which can be time consuming, stressful to the calf and is invasive by nature. A non-invasive technique that is gaining recognition is thermal imaging. This study investigated the use of thermal imaging as a technique to assess core body temperature in pre-weaned artificially reared calves. A total of 125 male and female calves had rectal temperatures measured daily from day 7 until day 40 of life, and at the same time had a thermal image taken of the area around the medial canthus of the eye. A weak correlation (r = 0.28) was found between calf rectal temperature and thermal image temperature. A multivariable predictive model for core body temperature increased the correlation (r = 0.32) when including the environmental parameters of air temperature (p < .001) and wind speed (p < .001) as well as reconstituted milk replacer consumption (p < .01). The effectiveness of a predictive model including these parameters for the detection of calves with a core body temperature ≥ 39.5 °C was examined and found to have a sensitivity of 0% and a specificity of 100%. The results of this study demonstrate the need to take thermal environmental parameters into consideration when using thermal imaging to assess body temperature. However, the results suggest that accurate measures of core body temperature using thermal imaging cannot be achieved under commercial farm conditions. Further research is needed to determine what other factors could be measured to increase predictive ability.


Assuntos
Temperatura Corporal , Doenças dos Bovinos/diagnóstico , Febre/veterinária , Animais , Bovinos , Feminino , Febre/diagnóstico , Masculino
17.
J Dairy Sci ; 103(7): 6511-6521, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32359992

RESUMO

Endometritis, diagnosed either by assessing the proportion of nucleated cells that are neutrophils (PMN%) following cytology of the endometrium or by assessing the degree of purulent material within the vagina (purulent vaginal discharge or PVD score), is prevalent among dairy cows. However, limited data exist as to the degree of variation among herds in the prevalence of endometritis diagnosed by these 2 methods. Thus, we undertook a study involving uterine cytological and vaginal sampling at a median of 41 d in milk of 1,807 cows from 100 seasonally breeding dairy herds in New Zealand. The optimal cut-point for PMN% was determined by receiver operator characteristic (ROC) curve analysis using conception to first artificial insemination (AI) as the outcome variable. The prevalence of disease was then calculated at the cow and herd levels, and an estimate of the effect of clustering of cow within a herd was calculated. Reproductive outcomes were collated and associations between endometritis and reproductive outcomes assessed using multivariable models. The optimal PMN% cut-point was ≥2%. The correlation of results for cows within a herd (the intraclass correlation) was 0.03, which was significant; hence, subsequent modeling accounted for this clustering. The cow-level prevalence of PMN% ≥2% was 27.0% [95% confidence interval (CI): 25.0 to 29.1%], whereas the mean within-herd prevalence of PMN% ≥2% was 27.1% (95% CI: 24.7 to 29.6%; range: 5.0 to 63.6%), and the prevalence among herds varied significantly. An elevated PMN% (≥2%) was significantly associated with a reduction in the proportion of cows conceiving to first AI (45.8 vs. 54.5%), a reduced proportion of cows submitted for AI in the first 3 wk of the seasonal breeding program (83.7 vs. 89.3%), and a lower proportion pregnant in the first 3 (44.4 vs. 55.4%) and 6 wk (67.5 vs. 76.4%) of the breeding program relative to cows with a low PMN% (i.e., <2%). A total of 24.6% of cows had a PVD score ≥2. The herd mean prevalence of PVD score ≥2 was 25.1% (95% CI: 22.5 to 27.7%; range: 5.0 to 65.0%) and varied significantly among herds. The level of agreement (kappa) between the PVD score and PMN% was low (16.8%) and nonsignificant. The effects of PVD score and PMN% on reproductive outcomes were independent. The within-herd median prevalence of endometritis based on combining both diagnostic tests and using a Bayesian latent class model was 22.9% (Bayesian 95% CI: 10.4 to 40.1%). We conclude that more than one-fifth of dairy cows have endometritis diagnosed either by PMN% or PVD in seasonal breeding herds when assessed at an average of 41 DIM, which was, on average, 30 d before the start of the seasonal breeding program. There is large and unexplained variation in prevalence of endometritis among herds. The 2 diagnostic methods were both associated with reproductive outcomes but have low levels of agreement between them and their effects appear to be independent.


Assuntos
Doenças dos Bovinos/diagnóstico , Endometrite/veterinária , Útero/citologia , Descarga Vaginal/veterinária , Animais , Teorema de Bayes , Bovinos , Doenças dos Bovinos/epidemiologia , Endometrite/diagnóstico , Endometrite/epidemiologia , Feminino , Humanos , Nova Zelândia/epidemiologia , Gravidez , Prevalência , Descarga Vaginal/diagnóstico
18.
Vet Ital ; 56(1)2020 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-32343092

RESUMO

A duplex real­time PCR was developed and validated for the simultaneous detection of Brucella and bovine alphaherpesvirus­1 (BoHV­1) from bovine clinical specimens. The bcsp31 gene of Brucella and gB gene of BoHV­1 were used as targets in the assay. The limit of detection for BoHV­1 was 0.03 TCID50 of virus and 10 plasmid copies containing the target gene while for Brucella it was 4.1 × 101 CFUs. Intra­assay and inter­assay values showed high repeatability and reproducibility of the assay. The diagnostic sensitivity (dsn) and diagnostic specificity (dsp) of the duplex assay were determined by screening 443 clinical specimens and comparing the results with the respective individual assays. The dsn and dsp for detection of Brucella were found to be 95.24% and 95.65%, respectively whereas for BoHV­1, the dsn (100%) and dsp (99.47%) were slightly higher. The duplex assay had a very good degree of agreement with the respective individual real­time PCR test {kappa value 0.97 for Brucella and 0.95 for BoHV­1}. The results of the current study suggest that the duplex assay would be a cost­effective and time­saving alternative for the individual real­time PCR assay for the detection of Brucella and BoHV­1.


Assuntos
Brucella/isolamento & purificação , Brucelose/veterinária , Doenças dos Bovinos/diagnóstico , Infecções por Herpesviridae/veterinária , Herpesvirus Bovino 1/isolamento & purificação , Animais , Brucella/genética , Brucelose/complicações , Brucelose/diagnóstico , Bovinos , Doenças dos Bovinos/sangue , Infecções por Herpesviridae/complicações , Infecções por Herpesviridae/diagnóstico , Herpesvirus Bovino 1/genética , Reação em Cadeia da Polimerase em Tempo Real , Sensibilidade e Especificidade
19.
J Vet Diagn Invest ; 32(3): 401-408, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32306865

RESUMO

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


Assuntos
Anticorpos Antiprotozoários/sangue , Doenças dos Bovinos/diagnóstico , Coccidiose/veterinária , Ensaio de Imunoadsorção Enzimática/veterinária , Neospora/isolamento & purificação , Proteínas de Protozoários/análise , Proteínas Recombinantes/análise , Animais , Bovinos , Doenças dos Bovinos/parasitologia , Coccidiose/diagnóstico , Coccidiose/parasitologia , Ensaio de Imunoadsorção Enzimática/métodos
20.
Vet Parasitol ; 281: 109101, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32302944

RESUMO

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


Assuntos
Coccidiose/veterinária , Ensaio de Imunoadsorção Enzimática/veterinária , Neospora/imunologia , Animais , Bovinos , Doenças dos Bovinos/diagnóstico , Coccidiose/diagnóstico , Técnica Indireta de Fluorescência para Anticorpo , Neospora/genética , Proteínas de Protozoários/imunologia , Proteínas Recombinantes/imunologia , Sensibilidade e Especificidade , Ovinos , Doenças dos Ovinos/diagnóstico
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