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1.
Artigo em Inglês | MEDLINE | ID: mdl-37670843

RESUMO

This study investigated the emergence and use of Twitter, as of July 2023 being rebranded as X, as the main forum for social media communication in parasitology. A dataset of tweets was constructed using a keyword search of Twitter with the search terms 'malaria', 'Plasmodium', 'Leishmania', 'Trypanosoma', 'Toxoplasma' and 'Schistosoma' for the period from 2011 to 2020. Exploratory data analyses of tweet content were conducted, including language, usernames and hashtags. To identify parasitology topics of discussion, keywords and phrases were extracted using KeyBert and biterm topic modelling. The sentiment of tweets was analysed using VADER. The results show that the number of tweets including the keywords increased from 2011 (for malaria) and 2013 (for the others) to 2020, with the highest number of tweets being recorded in 2020. The maximum number of yearly tweets for Plasmodium, Leishmania, Toxoplasma, Trypanosoma and Schistosoma was recorded in 2020 (2804, 2161, 1570, 680 and 360 tweets, respectively). English was the most commonly used language for tweeting, although the percentage varied across the searches. In tweets mentioning Leishmania, only ∼37% were in English, with Spanish being more common. Across all the searches, Portuguese was another common language found. Popular tweets on Toxoplasma contained keywords relating to mental health including depression, anxiety and schizophrenia. The Trypanosoma tweets referenced drugs (benznidazole, nifurtimox) and vectors (bugs, triatomines, tsetse), while the Schistosoma tweets referenced areas of biology including pathology, eggs and snails. A wide variety of individuals and organisations were shown to be associated with Twitter activity. Many journals in the parasitology arena regularly tweet about publications from their journal, and professional societies promote activity and events that are important to them. These represent examples of trusted sources of information, often by experts in their fields. Social media activity of influencers, however, who have large numbers of followers, might have little or no training in science. The existence of such tweeters does raise cause for concern to parasitology, as one may start to question the quality of information being disseminated.

2.
Pathogens ; 12(8)2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37624027

RESUMO

Infectious diseases of cattle, including bovine viral diarrhea (BVD), pose a significant health threat to the global livestock industry. This study aimed to investigate the prevalence and risk factors associated with bovine viral diarrhea virus (BVDV) infections in cattle populations through a systematic review and meta-analysis. PubMed, Web of Science, and Scopus were systematically searched for relevant articles reporting the prevalence of and associated risk factors in studies published between 1 January 2000 and 3 February 2023. From a total of 5111 studies screened, 318 studies were included in the final analysis. BVDV prevalence in cattle populations was estimated using various detection methods. The analysis detected heterogeneity in prevalence, attributed to detection techniques and associated risk factors. Antibody detection methods exhibited a higher prevalence of 0.43, reflecting the cumulative effect of detecting both active and past infections. Antigen detection methods showed a prevalence of 0.05, which was lower than antibody methods. A prevalence of 0.08 was observed using nucleic acid detection methods. The health status of the examined cattle significantly influenced the prevalence of BVDV. Cattle with bovine respiratory disease complex (BRDC) exhibited higher antibody (prevalence of 0.67) and antigen (prevalence 0.23) levels compared to cattle with reproductive problems (prevalence 0.13) or diarrhea (prevalence 0.01). Nucleic acid detection methods demonstrated consistent rates across different health conditions. Age of cattle influenced prevalence, with higher rates in adults compared to calves. Risk factors related to breeding and reproduction, such as natural or extensive breeding and a history of abortion, were associated with increased prevalence. Coinfections with pathogens like bovine herpesvirus-1 or Neospora caninum were linked to higher BVDV prevalence. Management practices, such as commingling, introducing new cattle, and direct contact with neighboring farms, also influenced prevalence. Herd attributes, including larger herd size, and the presence of persistently infected cattle, were associated with higher prevalence. These findings indicated the importance of detection methods and risk factors in BVDV epidemiological studies.

4.
Pathogens ; 10(10)2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34684212

RESUMO

Bovine viral diarrhoea virus (BVDV) is an economically important and highly prevalent virus of domestic cattle. Infections with BVDV may lead to both, reproductive and immunological effects that can result in widespread calf losses and increased susceptibility to diseases, such as mastitis and respiratory disease. While BVDV is generally considered to be host specific, it and other Pestivirus species, such as Border disease virus (BDV) in sheep, have been shown to be infecting species other than those from which they were originally isolated from. Recently BVDV was placed on the OIE's list of notifiable disease and control and eradication programmes for BVDV have been developed throughout much of Europe, the United States, and the United Kingdom. While some countries, including Sweden and Ireland have successfully implemented eradication programmes, other countries such as New Zealand and Australia are still in the early stages of BVDV control. Despite effective control methods, incursions of BVDV into previously cleared herds still occur. While the cause of these incursions is often due to lapses in control methods, the ability of ruminant pestiviruses to infect species other than cattle poses the question as to whether non-bovine species could be impeding the success of BVDV eradication and control. As such, the aim of this review is to make mention of what is known about the cross-species transmission of BVDV, BDV and other pestiviruses between cattle and non-bovine ungulate species and draw conclusions as to the risk non-bovine species pose to the successful control and eradication of BVDV from cattle.

5.
Vet Rec ; 188(3): e6, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34651881

RESUMO

BACKGROUND: Acute bovine viral diarrhoea virus (BVDV) infections in sheep are largely sub-clinical although infections of pregnant ewes have shown to result in significant fetal losses and persistently infected lambs. However, the extent and severity of abnormalities in lambs infected with BVDV in utero is still largely unknown. METHODS: Twenty-two ewes were experimentally infected with BVDV-1c between 59 and 69 days of gestation. Fifteen lambs were submitted for pathological examination and the abnormalities observed in lambs and fetuses characterised. RESULTS: Six lambs were identified as BVDV negative, and nine were identified as BVDV positive. Anasarca and cholestatic hepatopathy was observed in four BVDV positive lambs and associated with ewes with early seroconversion. One BVDV positive lamb was born with muscular tremors and a hairy coat associated with primary follicular dysplasia, a developmental abnormality normally associated with border disease infected lambs. CONCLUSION: If similar lambing outcomes are identified in a commercial setting then BVDV should be considered, particularly in areas where sheep regularly come in to contact with cattle. In addition, as far as the authors are aware, this is the first reported case of a 'hairy shaker' lamb born as a result of an infection with BVDV-1c in Australia.


Assuntos
Doença das Mucosas por Vírus da Diarreia Viral Bovina , Doenças dos Bovinos , Vírus da Diarreia Viral Bovina , Doenças dos Ovinos , Animais , Anticorpos Antivirais , Bovinos , Diarreia/veterinária , Feminino , Gravidez , Soroconversão , Ovinos
6.
Artigo em Inglês | MEDLINE | ID: mdl-35284864

RESUMO

In recent times, the use of social media for the dissemination of "news and views" in parasitology has increased in popularity. News, Twitter and Blogs have emerged as commonplace vehicles in the knowledge dissemination and transfer process. Alternative metrics ("altmetrics"), based on social media mentions have been proposed as a measure of societal impact, although firm evidence for this relationship is yet to be found. Nevertheless, increasing amounts of data on "altmetrics" are being analysed to identify the nature of the unknown impact that social media is generating. Here, we examine the recent, and increasing use of social media in the field of parasitology and the relationship of "altmetrics" with more traditional bibliometric indicators, such as article citations and journal metrics. The analyses document the rise and dominance of Twitter as the main form of social media occurring in the discipline of parasitology and note the contribution to this trend of Twitter bots that automatically tweet about publications. We also report on the use of the social referencing platform Mendeley and its correlation to article citations; Mendeley reader numbers are now considered to provide firm evidence on the early impact of research. Finally, we consider the Twitter profile of 31 journals publishing parasitology research articles (by volume of papers published); we show that 13 journals are associated with prolific Twitter activity about parasitology. We hope this study will stimulate not only the continued and responsible use of social media to disseminate knowledge about parasitology for the greater good, but also encourage others to further investigate the impact and benefits that altmetrics may bring to this discipline.

7.
Parasitology ; 147(14): 1643-1657, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32867863

RESUMO

Bibliometric methods were used to analyse the major research trends, themes and topics over the last 30 years in the parasitology discipline. The tools used were SciMAT, VOSviewer and SWIFT-Review in conjunction with the parasitology literature contained in the MEDLINE, Web of Science, Scopus and Dimensions databases. The analyses show that the major research themes are dynamic and continually changing with time, although some themes identified based on keywords such as malaria, nematode, epidemiology and phylogeny are consistently referenced over time. We note the major impact of countries like Brazil has had on the literature of parasitology research. The increase in recent times of research productivity on 'antiparasitics' is discussed, as well as the change in emphasis on different antiparasitic drugs and insecticides over time. In summary, innovation in parasitology is global, extensive, multidisciplinary, constantly evolving and closely aligned with the availability of technology.


Assuntos
Mineração de Dados/estatística & dados numéricos , Parasitologia/tendências , Bibliometria , Bases de Dados Factuais
8.
Pathogens ; 9(6)2020 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-32585955

RESUMO

BACKGROUND: Neospora caninum has been recognised world-wide, first as a disease of dogs, then as an important cause of abortions in cattle for the past thirty years. Over that time period, there have been improvements in the diagnosis of infection and abortion, new tests have been developed and validated, and it is timely to review progress to date. METHODS: Bibliometric methods were used to identify major trends and research topics present in the published literature on N. caninum. The tools used were SWIFT-Review, VOSviewer and SciMAT, along with the published papers found in the MEDLINE, Dimensions and Web of Science databases. A systematic review of the published Neospora literature (n = 2933) was also carried out via MEDLINE and systematically appraised for publications relevant to the pathogenesis, pathology and diagnosis of Neospora abortions. RESULTS: A total of 92 publications were included in the final analysis and grouped into four main time periods. In these four different time periods, the main research themes were "dogs", "abortion", "seroprevalence" and "infection". Diagnostics, including PCR, dominated the first two time periods, with an increased focus on transmission and abortions, and its risk factors in cattle. CONCLUSIONS: Longitudinal analyses indicated that the main themes were consistently investigated over the last 30 years through a wide range of studies, with evolving emphasis initially on dogs and diagnostic test development, followed by application to cattle, the identification of the risk factors leading to abortion, and in the latter time periods, an understanding of the immunity and a search for vaccines.

9.
PLoS One ; 15(4): e0231162, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32271816

RESUMO

In Hong Kong, there is a cattle population of ~1,200 individuals of uncertain origin and genetic diversity. This population shows heterogeneous morphology, both in body type and pigmentation. Once used as draught animals by the local farmers, they were abandoned around the 1970s due to changes in the economy, and since then have lived as feral populations. To explore the origins of these cattle, we analysed ~50k genotype data of 21 Hong Kong feral cattle, along with data from 703 individuals of 36 cattle populations of European, African taurine, and Asian origin, the wild x domestic hybrid gayal, plus two wild bovine species, gaur and banteng. To reduce the effect of ascertainment bias ~4k loci that are polymorphic in the two wild species were selected for further analysis. The stringent SNP selection we applied resulted in increased heterozygosity across all populations studies, compared with the full panel of SNP, thus reducing the impact of ascertainment bias and facilitating the comparison of divergent breeds of cattle. Our results showed that Hong Kong feral cattle have relatively high levels of genetic distinctiveness, possibly due to the low level of artificial selection, and a likely common ancestry with wild species. We found signs of a putative taurine introgression, probably dating to the import of north European breeds during the British colonialism of Hong Kong. We showed that Hong Kong feral cattle, are distinct from Bos taurus and Bos indicus breeds. Our results highlight the distinctiveness of Hong Kong feral cattle and stress the conservation value of this indigenous breed that is likely to harbour adaptive genetic variation, which is a fundamental livestock resource in the face of climate change and diversifying market demands.


Assuntos
Animais Selvagens/genética , Bovinos/genética , Filogenia , Polimorfismo de Nucleotídeo Único/genética , Animais , Feminino , Variação Genética , Hong Kong , Masculino , Análise de Componente Principal
10.
Vet Parasitol ; 277: 108967, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31812121

RESUMO

Neospora caninum infection is regarded as one of the most important infectious causes of abortion in dairy cattle. To intervene in its spread, four potential controls including test-and-cull, medication, vaccination, and selective breeding are considered and assessed in this study. The cost of each control, together with the inevitable annual loss due to population dynamics, is adopted as an assessment criterion from an economic point of view. By performing simulation and sensitivity analysis, our results demonstrate that compared with each single control, combined controls are worthwhile with better financial outcomes. For farm affected with significant prevalence (equal to or greater than 30%), vaccine treatment is the most effective and economical option among all control strategies. On the other hand, for farm where prevalence is relatively low (around 10%), combined control, by applying vaccination followed with test-and-cull, medication or selective breeding, could be alternative treatment to provide better financial outcome against single control in an observed period.


Assuntos
Doenças dos Bovinos/prevenção & controle , Doenças dos Bovinos/terapia , Coccidiose/veterinária , Terapia Combinada/veterinária , Animais , Antiparasitários/uso terapêutico , Cruzamento , Bovinos , Doenças dos Bovinos/economia , Coccidiose/economia , Coccidiose/prevenção & controle , Coccidiose/terapia , Indústria de Laticínios/economia , Neospora/fisiologia , Dinâmica Populacional , Vacinas Protozoárias
11.
PLoS One ; 14(8): e0220335, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31393897

RESUMO

Smallholder large ruminant production in Lao People's Democratic Republic (Laos) is characterised by low reproductive efficiency. To determine if common abortifacient bovid infectious diseases are involved, a serological investigation was conducted. Sera was collected from stored and fresh cattle (n = 390) and buffalo (n = 130) samples from 2016-18 from, and then examined for associations in a retrospective risk factor study of 71 herds. The sera were assayed for antibodies to Neospora caninum, bovine viral diarrhoea virus (BVDV), Leptospira interrogans serovar Hardjo and Brucella abortus using commercially available enzyme-linked immunosorbent assay kits. These pathogens were detected in buffalo samples at 78.5% (95% CI 71.4-85.6), 0%, 2.3% (95% CI 0-4.9) and 0%, respectively, and in cattle at 4.4% (95% CI 2.4-6.4), 7.7% (95% CI 3.1-12.3), 12.8% (95% CI 9.5-16.1) and 0.26% (95% CI 0-0.8), respectively. Exposure of buffalo to N. caninum was positively associated with buffalo age, with a predicted seropositivity at birth of 52.8%, increasing to 97.2% by 12 years of age (p = 0.037). Exposure of cattle to L. interrogans serovar Hardjo was more prevalent in females compared to males, was associated with higher titres of BVDV, and was more prevalent in the wet season compared to the dry season. Exposure of cattle to BVDV was more prevalent in males compared to females, the wet and dry seasons were comparable, and was associated with rising antibody titres against N. caninum and L. interrogans serovar Hardjo. The risk factor survey identified that the probability of herds being N. caninum positive increased with farmer age, if farmers believed there were rodents on farm, and if farmers weren't aware that canids or rodents could contaminate bovid feed on their farm. The probability of a herd being positive to L. interrogans serovar Hardjo increased on farms where multiple cows shared the same bull, where farmers had lower husbandry knowledge, and on farms that used water troughs. The probability of a herd being BVDV seropositive increased with increasing herd size and increasing titres to N. caninum. The benchmarking of bovid exposure to emerging abortifacient pathogens and identification of their risk factors potentially informs disease prevention strategies, supporting efforts to establish a biosecure beef supply for enhanced smallholder livestock productivity, public health and food security in Laos and surrounding countries.


Assuntos
Doença das Mucosas por Vírus da Diarreia Viral Bovina , Búfalos , Coccidiose , Vírus da Diarreia Viral Bovina/imunologia , Leptospira interrogans/imunologia , Leptospirose , Neospora/imunologia , Adulto , Animais , Doença das Mucosas por Vírus da Diarreia Viral Bovina/epidemiologia , Doença das Mucosas por Vírus da Diarreia Viral Bovina/imunologia , Búfalos/imunologia , Búfalos/microbiologia , Búfalos/parasitologia , Búfalos/virologia , Bovinos/imunologia , Bovinos/microbiologia , Bovinos/parasitologia , Bovinos/virologia , Coccidiose/epidemiologia , Coccidiose/imunologia , Coccidiose/veterinária , Feminino , Humanos , Laos , Leptospirose/epidemiologia , Leptospirose/imunologia , Leptospirose/veterinária , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco
12.
Front Vet Sci ; 5: 222, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30333984

RESUMO

Infectious causes of reproductive failure in cattle are important in Australia and New Zealand, where strict biosecurity protocols are in place to prevent the introduction and spread of new diseases. Neospora caninum ranks highly as an important cause of reproductive wastage along with fungal and bacterial infections. Brucella, a leading cause of abortion elsewhere in the world, is foreign, following successful programs to control and eradicate the disease. Leptospirosis in cattle is largely controlled by vaccination, while Campylobacter and Tritrichomonas infections occur at low rates. In both countries, Bovine Viral Diarrhea virus (BVDV) infection rates as the second most economically important disease of cattle and one that also has an effect on reproduction. Effective disease control strategies require rapid diagnoses at diagnostic laboratories. To facilitate this process, this review will discuss the infectious causes of reproductive losses present in both countries, their clinical presentation and an effective pathway to a diagnosis.

13.
Vet Rec ; 182(12): 352, 2018 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-29511108

RESUMO

This study investigated the transmission of bovine viral diarrhoea virus (BVDV)-1c from a persistently infected (PI) neonate lamb to naïve sheep and cattle using three treatment groups: four naïve ewes and their five lambs, which were copaddocked with the PI lamb; five steers, which were housed in a paddock adjacent to the PI lamb; and five steers, which had direct but limited exposure to the PI lamb. Serum samples were collected and tested for BVDV-specific antibodies. Serum samples from the PI lamb, from day of birth to eight weeks of age, were tested for BVDV-specific antibodies and antigen and submitted for quantitative PCR to determine the viral load present at each week of age. Only one lamb from the copaddocked group developed BVDV-specific antibodies following comingling while all the steers in both the cattle treatment groups remained BVDV antibody negative. Quantitative PCR results from the PI lamb showed lower viral loads from day of birth to six weeks of age, compared with the results at seven and eight weeks of age. This may reflect maternal colostral BVDV antibody concentrations in the neonate lamb or other viral properties.


Assuntos
Doença das Mucosas por Vírus da Diarreia Viral Bovina/transmissão , Vírus da Diarreia Viral Bovina Tipo 1/isolamento & purificação , Infecções por Pestivirus/veterinária , Doenças dos Ovinos/transmissão , Animais , Animais Recém-Nascidos , Anticorpos Antivirais/sangue , Doença das Mucosas por Vírus da Diarreia Viral Bovina/virologia , Bovinos , Vírus da Diarreia Viral Bovina Tipo 1/imunologia , Infecções por Pestivirus/transmissão , Infecções por Pestivirus/virologia , Ovinos , Doenças dos Ovinos/virologia
14.
Pathogens ; 7(1)2018 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-29361748

RESUMO

This review outlines the history of bovine viral diarrhoea virus (BVDV) and the current situation in Australia and New Zealand. BVDV has been reported as present in cattle from both countries for close to 60 years. It rates as the second most economically significant disease afflicting cattle, and is highly prevalent and spread throughout the beef and dairy industries. While other cattle diseases have been the subject of government control and eradication, infection with BVDV is presently not. Eradication has been undertaken in many other countries and been judged to be a good investment, resulting in positive economic returns. Presently, Australia and New Zealand have adopted a non-compulsory approach to control schemes, initiated and managed by farmers and veterinarians without the ultimate goal of eradication. Moving towards eradication is possible with the infrastructure both countries possess, but will require additional resources, coordination, and funding from stakeholders to move to full eradication.

15.
Parasitol Int ; 67(2): 209-212, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29217417

RESUMO

Fleas are commonly recorded on stray as well as domestic dogs and cats in Hong Kong. Fleas can be a major cause of pruritus in dogs and cats and also vectors of potentially zoonotic bacteria in the genera Rickettsia and Bartonella. Morphological examination of 174 fleas from dogs and cats living in Hong Kong revealed only cat fleas (Ctenocephalides felis). Cytochrome c oxidase subunit 1 gene (cox1) genotyping of 20 randomly selected specimens, revealed three cox1 haplotypes (HK-h1 to HK-h3). The most common haplotype was HK-h1 with 17 specimens (17/20, 85%). HK-h1 was identical to cox1 sequences of fleas in Thailand and Fiji. HK-h1 and HK-h2 form a distinct cat flea cox1 clade previously recognized as the Clade 3. HK-h3 forms a new Clade 6. A multiplex Bartonella and Rickettsia real-time PCR of DNA from 20 C. felis found Bartonella and Rickettsia DNA in three (15%) and ten (50%) C. felis, respectively. DNA sequencing confirmed the presence of R. felis, B. clarridgeiae and Bartonella henselae. This is the first reported study of that kind in Hong Kong, and further work is required to expand the survey of companion animals in the geographical region. The sampling of fleas on domestic cats and dogs in Hong Kong revealed them to be exclusively infested by the cat flea and to be harbouring pathogens of zoonotic potential.


Assuntos
Bartonella/isolamento & purificação , Ctenocephalides/microbiologia , Rickettsia felis/isolamento & purificação , Animais , Bartonella/genética , Bartonella/patogenicidade , Infecções por Bartonella/epidemiologia , Gatos/parasitologia , Ctenocephalides/genética , Cães/parasitologia , Complexo IV da Cadeia de Transporte de Elétrons , Infestações por Pulgas/epidemiologia , Infestações por Pulgas/parasitologia , Infestações por Pulgas/transmissão , Haplótipos , Hong Kong/epidemiologia , Reação em Cadeia da Polimerase Multiplex , Infecções por Rickettsia/epidemiologia , Rickettsia felis/genética , Rickettsia felis/patogenicidade , Análise de Sequência de DNA
16.
J Vet Diagn Invest ; 29(2): 181-185, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28178907

RESUMO

Effective control and the eventual eradication of Bovine viral diarrhea virus (BVDV) from cattle populations depend on the accurate identification of infected animals. Although typically a disease agent of cattle, BVDV is known to infect a wide variety of nonbovine species, including sheep. However, validation of serologic tests in these nonbovine species, particularly sheep, is lacking. We analyzed 99 sheep sera (57 samples from Pestivirus-naive sheep, and 42 samples from BVDV-inoculated sheep) in order to investigate 3 serologic tests: the agarose gel immunodiffusion (AGID) and 2 commercial enzyme-linked immunosorbent assays (ELISAs) for detection of BVDV antibodies. At the manufacturer's cutoff thresholds, the AGID performed with 95.2% diagnostic sensitivity; ELISA-A performed with sensitivity of 90.5% and ELISA-B with 69.1%. All 3 tests performed with 100% diagnostic specificity. Two-graph receiver operating characteristic analysis showed that performance characteristics were optimized, such that both diagnostic sensitivity and diagnostic specificity were >95% for both ELISAs, if the thresholds were altered to 34.9% inhibition for ELISA-A and 63.5 signal-to-noise ratio for ELISA-B.


Assuntos
Anticorpos Antivirais/sangue , Doença das Mucosas por Vírus da Diarreia Viral Bovina/prevenção & controle , Vírus da Diarreia Viral Bovina/imunologia , Doenças dos Ovinos/prevenção & controle , Animais , Doença das Mucosas por Vírus da Diarreia Viral Bovina/virologia , Bovinos , Ensaio de Imunoadsorção Enzimática/veterinária , Imunodifusão/veterinária , Sensibilidade e Especificidade , Testes Sorológicos/veterinária , Ovinos , Doenças dos Ovinos/sangue , Doenças dos Ovinos/virologia
17.
Vet J ; 215: 76-81, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27160006

RESUMO

Detecting antibodies formed in serum in response to infection is the traditional function of serology. Diagnostic modalities have included complement fixation tests, agar gel immune-diffusion, radioimmunoassay, ELISA and immunofluorescence. More recent technology now allows for the direct detection of pathogens by PCR. This review details the options for diagnostic testing using specimen types other than serum, identifying the advantages and disadvantages of these options and providing evidence for more widespread use of these techniques and specimen types.


Assuntos
Doenças dos Animais/diagnóstico , Técnicas e Procedimentos Diagnósticos/veterinária , Animais , Animais Domésticos
18.
J Vet Diagn Invest ; 28(3): 345-9, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27016723

RESUMO

Antigen enzyme-linked immunosorbent assay (ELISA) is used for the detection of Bovine viral diarrhea virus persistently infected (BVDV PI) cattle; however, colostrum-derived antibodies may interfere with antigen detection in serum from young PI calves. Our study aimed to assess serum pretreatment methods for reducing such interference. Dilution of PI serum with serum containing specific antibody showed that antibody levels equivalent to those observed in colostrum-fed calves were able to eliminate all antigen signals in a serum sample. Serum was treated with ethylenediamine tetra-acetic acid at pH 4.5, 5.5, 6.5, and 7.5, then boiled, centrifuged, and the supernatant-recovered. BVDV antibody was undetectable by ELISA in supernatants from treated samples, and the antigen ELISA signal was improved. Maximum antigen signal recovery of >90% was achieved at pH 5 ± 0.5. When this optimal treatment method was applied to field samples from 3 PI calves (which were negative in the antigen-capture ELISA without treatment), the antigen signal improved and gave a positive result in each case. Pretreatment may provide an improvement in the detection of young PI calves.


Assuntos
Doença das Mucosas por Vírus da Diarreia Viral Bovina/diagnóstico , Colostro/imunologia , Vírus da Diarreia Viral Bovina/isolamento & purificação , Ensaio de Imunoadsorção Enzimática/veterinária , Animais , Animais Recém-Nascidos , Anticorpos Antivirais/sangue , Antígenos Virais/sangue , Doença das Mucosas por Vírus da Diarreia Viral Bovina/sangue , Doença das Mucosas por Vírus da Diarreia Viral Bovina/virologia , Bovinos , Vírus da Diarreia Viral Bovina/imunologia , Feminino , Gravidez
19.
J Vet Diagn Invest ; 28(1): 50-3, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26699518

RESUMO

Colostrum may have the ability to improve the diagnostic accuracy of some tests when compared to serum for important livestock diseases because of the high concentrations of immunoglobulins present within this sample type. The ELISA for Johne's disease is one such test, as it suffers from low sensitivity when testing serum samples collected during the subclinical stage of infection. Blood and colostrum samples were collected from 34 Jersey dairy cows and tested for antibodies against Mycobacterium avium subspecies paratuberculosis (MAP) by ELISA. Fecal samples were also collected and tested by a high-throughput Johne's polymerase chain reaction (HT-J PCR) assay and fecal culture (FC), with the latter being used as the reference test. A receiver operating characteristic (ROC) analysis was performed, and the area under the curve (AUC) was calculated. The HT-J PCR and FC results were also compared. Of the 34 cows in this study, 4 had FC results consistent with MAP infection. The HT-J PCR did not identify any FC-positive cows. Using a 1:20 dilution and sample-to-positive (S/P) ratio cutoff threshold of 0.15, the relative sensitivity values of both serum (AUC 0. 56) and colostrum (AUC 0.63) were 0%. With lower sample dilutions, the relative sensitivity values of serum were 0% (1:2, AUC 0.62; 1:5, AUC 0.55); however, the relative sensitivity value of colostrum was 75% (95% confidence interval [CI]: 19-99%) at a dilution of 1:5, S/P ratio cutoff threshold of 0.15, and AUC of 0.73 (95% CI: 0.55-0.87). The testing of colostrum samples for MAP-specific antibodies by ELISA may provide improved identification of animals in the early stages of infection with MAP when compared with serum samples.


Assuntos
Doenças dos Bovinos/microbiologia , Mycobacterium avium subsp. paratuberculosis/imunologia , Paratuberculose/microbiologia , Criação de Animais Domésticos , Animais , Anticorpos Antibacterianos/sangue , Bovinos , Doenças dos Bovinos/sangue , Colostro/virologia , Indústria de Laticínios , Ensaio de Imunoadsorção Enzimática/veterinária , Fezes/microbiologia , Feminino , Mycobacterium avium subsp. paratuberculosis/isolamento & purificação , Reação em Cadeia da Polimerase/veterinária , Gravidez , Curva ROC , Sensibilidade e Especificidade
20.
Vet Parasitol ; 212(3-4): 75-9, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26298507

RESUMO

A number of countries in the world have reported infections with Neospora caninum in water buffalo (Bubalus bubalis), from Africa to Asia, Europe and South America and recently Australia. In general, clinical manifestations (such as abortion) seem rare, which has raised the prospect that buffalo may be inherently resistant to clinical effects of N. caninum infection. Worldwide, the seroprevalence of N. caninum infection (as a measure of exposure determined by the detection of antibody) in buffalo is high, at approximately 48%. This reported seroprevalence is three or four times higher than that reported from the world's cattle populations, which have collective seroprevalence rates of 16.1% for dairy cattle and 11.5% for beef cattle. However, there is a lack of standardisation in seroprevalence studies and some studies may well under-estimate the true level of infection. Epidemiologic evidence supports post-natal transmission, and in utero transmission has also been demonstrated. The causes for water buffalo to have markedly higher seroprevalence but apparently lower neosporosis abortion rates than cattle warrant further investigation.


Assuntos
Búfalos/parasitologia , Coccidiose/veterinária , Neospora/isolamento & purificação , Animais , Coccidiose/epidemiologia , Coccidiose/parasitologia , Saúde Global , Estudos Soroepidemiológicos
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