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1.
Rev Bras Parasitol Vet ; 28(3): 465-472, 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31483037

RESUMO

To identify susceptible and resistant Haematobia irritans cows, horn flies were counted biweekly for 3 years in a herd of 25 Sindhi cows. Repeated measures linear mixed models were created including cow as a random factor. The results were analyzed by: 1) observing horn fly counts, considering fly-susceptible cows with infestations appearing in the upper quartile more than 50% of the weeks and in the lower quartile less than 20% of the weeks, and fly-resistant cows those that the number of flies was in the lower quartile more than 50% of the weeks and in the upper quartile less than 20%; 2) by the best linear unbiased predictions (BLUPs), to evaluate the cow effect on fly counts. Fly-susceptible cows were those in which the infestation appeared in the 90th percentile of the BLUPs, whereas fly-resistant cows appeared in the 10th percentile. For the observational method the individuals identified as resistant varied between 8% and 20% and 8% to 12% were susceptible. For the BLUP method, the rates of susceptible and resistant cows were 12%. The agreement among methods suggests that susceptible cows can be identified by observations of fly counts, allowing for selective breeding, culling or treatment.


Assuntos
Doenças dos Bovinos/parasitologia , Suscetibilidade a Doenças , Ectoparasitoses/veterinária , Muscidae , Animais , Bovinos , Estações do Ano
2.
Vet Parasitol ; 273: 32-35, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31442890

RESUMO

This study looked to assess the stability of Cryptosporidium parvum genotypes in calves between the final day of treatment with the antiprotozoal halofuginone lactate and seven days post-treatment. Paired faecal samples were collected on the final day of treatment and seven days later from 54 calves across seven farms in South-west England. The presence of Cryptosporidium species was detected using polymerase chain reaction targeting the 18 s rDNA. The presence and genotype of C. parvum was determined by PCR and amplicon sequencing targeting the gp60 locus. On farms where C. parvum was detected at both sampling times there was a distinct genotype shift. Detection of gp60 genotype IIaA15G2R1 decreased from 40% to 7% while IIaA17G1R1 increased from 0% to 41%, supplemented by IIaA16G3R1 in one sample. A shift in C. parvum genotypes present in calves within a one week sampling timeframe has not been described prior to this study, indicating that the timeframe is likely suitable for observing variation in C. parvum populations and interactions with antiprotozoal control strategies.


Assuntos
Doenças dos Bovinos/parasitologia , Criptosporidiose/parasitologia , Cryptosporidium parvum/genética , Animais , Antiprotozoários/uso terapêutico , Bovinos , Doenças dos Bovinos/tratamento farmacológico , Criptosporidiose/tratamento farmacológico , Inglaterra , Fezes/parasitologia , Genes de Protozoários/genética , Genótipo , RNA Ribossômico 18S/genética
3.
Vet Parasitol ; 273: 45-51, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31442892

RESUMO

Fasciola gigantica and hybrid Fasciola are distributed throughout Asia. Herein, we investigated the species of the Fasciola fluke distributed in three hotspots of fascioliasis in Cambodia. A total of 92 flukes collected from 21 slaughtered cattle from Kandal (44), Battambang (41), and Kratie (7) Provinces were identified as F. gigantica using multiplex PCR for a nuclear phosphoenolpyruvate carboxykinase (PEPCK) gene. The overall prevalence of F. gigantica infestation was 7.14% (21/294). Phylogenetic as well as population genetics analyses were performed using the mitochondrial NADH dehydrogenase subunit 1 (ND1). The 19 ND1 haplotypes were identified from Cambodian F. gigantica (haplotype diversity, 0.83). All of the haplotypes were classified into F. gigantica haplogroup C, which includes ND1 haplotypes detected from Thailand, Vietnam, Indonesia, Myanmar, and China. Among haplogroup C, novel and unique haplotypes of Cambodia were found in the Battambang and Kandal Provinces, and the nucleotide diversity of the Cambodian population (0.00532) was the highest. Pairwise fixation indices among the F. gigantica populations from these countries indicated that the Cambodian and Thailand populations were related to each other. The highest genetic diversity in the Cambodian population suggests that F. gigantica in Cambodia may be the ancestor of the populations in Southeast Asian countries. Most likely, livestock movement, including Zebu cattle, played an important role in the transmission of F. gigantica. In this study, the hybrid Fasciola flukes that are commonly found in neighboring countries, were not found in Cambodia. Further comprehensive investigations of Fasciola prevalence should be conducted by analyzing a wider range of hosts throughout Cambodia to reach a more solid conclusion about the absence of hybrid flukes.


Assuntos
Distribuição Animal , Doenças dos Bovinos/parasitologia , Fasciola/classificação , Fasciola/genética , Fasciolíase/veterinária , Variação Genética , Animais , Ásia Sudeste/epidemiologia , Camboja , Bovinos , Doenças dos Bovinos/epidemiologia , Fasciolíase/epidemiologia , Fasciolíase/parasitologia , Haplótipos , NADH Desidrogenase/genética , Fosfotransferases/genética , Prevalência
4.
Vet Parasitol ; 273: 67-70, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31442896

RESUMO

Suckling calves are prone to Cryptosporidium infection. The variable degree of clinical disease is influenced by keeping conditions and immune status of the host, but diversity of isolate virulence may also contribute. The aim of the current study was to evaluate the cytopathogenic effects of 26 C. parvum field isolates by using a MTT assay in HCT-8 cell monolayers. Cell viability of monolayers inoculated with oocysts of the field isolates varied considerably with values of 17.7% (± 5.1%) to 99.5% (± 7.1%). A standard deviation of 18.6% was detected for cell viability of the in house reference strain, which were tested alongside in every assay. Field isolates were grouped in three categories of cytopathogenicity. Probably the length of storage has an effect on the level of the cell destruction category detected post infection in vitro. The applied tool may help to better understand the variable course of cryptosporidiosis in the field.


Assuntos
Doenças dos Bovinos/parasitologia , Criptosporidiose/parasitologia , Cryptosporidium parvum/patogenicidade , Animais , Bovinos , Linhagem Celular , Sobrevivência Celular , Células Epiteliais/citologia , Células Epiteliais/parasitologia , Interações Hospedeiro-Parasita/imunologia , Humanos , Virulência/imunologia
5.
Rev Bras Parasitol Vet ; 28(3): 410-415, 2019 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-31340249

RESUMO

In South America, fascioliasis caused by the trematode Fasciola hepatica is an anthropozoonosis disease associated with significant economic losses and poor animal welfare. The objective of this study was to determine the prevalence of F. hepatica in the liver of buffaloes slaughtered from 2003 to 2017 in Brazil, and to perform a forecast analysis of the disease for the next five years using the Autoregressive Integrated Moving Average (ARIMA) model. Data analysis revealed an incidence of 7,187 cases out of 226,561 individuals. The disease presented a considerable interannual variation (p<0.005). Fasciola hepatica was more prevalent in the southern states of Brazil; Paraná, Rio Grande do Sul, and Santa Catarina, presenting 11.9, 7.7, and 3.2% of infected livers, respectively. The high frequency of liver condemnation in Paraná was influenced by weather conditions. The ARIMA models calculated a constant trend of the disease, depicting an average of its future prevalence. The models also described a worse-case and a positive-case scenario, calculating the effects of intervention measurements. In reality, there is an urgent need for regular diagnostic in the animals (fecal and immune diagnose) and in the environment (intermediate host), in order to avoid the high rates of infection.


Assuntos
Búfalos/parasitologia , Doenças dos Bovinos/epidemiologia , Fasciolíase/veterinária , Animais , Brasil/epidemiologia , Bovinos , Doenças dos Bovinos/diagnóstico , Doenças dos Bovinos/parasitologia , Fasciolíase/diagnóstico , Fasciolíase/epidemiologia , Incidência , Prevalência
6.
Exp Parasitol ; 204: 107729, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31348914

RESUMO

The objectives of this study are to: (1) evaluate the in vitro acaricidal effect of 54 Metarhizium anisopliae strains, six Beauveria bassiana strains and one Purpureocilium lilacinum strain, against the larvae of two populations of Rhipicephalus microplus (multi-resistant and susceptible to chemical acaricides); and (2) determine the lethal concentrations required to eliminate the 50% (LC50) and 99% (LC99) of larvae through the use of entomopathogenic fungi (EF) with high acaricidal effects. The mortality percentage was evaluated by larval immersion tests at a dose of 1 × 108 conidia/mL for each fungal strain. For calculating LC50 and LC99, four doses (1 × 108, 1 × 107, 1 × 106 and 1 × 105) were used. Nine strains of M. anisopliae and the P. lilacinum strain showed a high mortality percentage in the R. microplus larvae of both populations. The best strains that showed the lowest values of LC50 and LC99 for tick elimination were MaV50 and PlV01. In conclusion, several strains of entomopathogenic fungi showed a high acaricidal effect against the R. microplus larvae of both populations, suggesting that these fungi might be a promissory adjuvant in the control of R. microplus, including those who are resistant. Finally, the discovery of a P. lilacinum strain with a high acaricidal effect is also reported.


Assuntos
Acaricidas/farmacologia , Fungos/patogenicidade , Controle Biológico de Vetores/métodos , Rhipicephalus/microbiologia , Microbiologia do Solo , Animais , Beauveria/patogenicidade , Bioensaio/veterinária , Bovinos , Doenças dos Bovinos/tratamento farmacológico , Doenças dos Bovinos/parasitologia , Doenças dos Bovinos/prevenção & controle , Feminino , Hypocreales/patogenicidade , Resistência a Inseticidas , Larva/efeitos dos fármacos , Larva/microbiologia , Dose Letal Mediana , Masculino , Metarhizium/patogenicidade , México , Rhipicephalus/efeitos dos fármacos , Infestações por Carrapato/tratamento farmacológico , Infestações por Carrapato/parasitologia , Infestações por Carrapato/veterinária , Virulência
7.
Parasit Vectors ; 12(1): 353, 2019 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-31311591

RESUMO

BACKGROUND: Faecal egg counts (FEC) and the FEC reduction test (FECRT) for assessing gastrointestinal nematode (GIN) infection and efficacy of anthelmintics are rarely carried out on ruminant farms because of the cost of individual analyses. The use of pooled faecal samples is a promising method to reduce time and costs, but few studies are available for cattle, especially on the evaluation of different pool sizes and FECRT application. METHODS: A study was conducted to assess FEC strategies based on pooled faecal samples using different pool sizes and to evaluate the pen-side use of a portable FEC-kit for the assessment of FEC on cattle farms. A total of 19 farms representing 29 groups of cattle were investigated in Italy and France. On each farm, individual faecal samples from heifers were collected before (D0) and two weeks after (D14) anthelmintic treatment with ivermectin or benzimidazoles. FEC were determined individually and as pooled samples using the Mini-FLOTAC technique. Four different pool sizes were used: 5 individual samples, 10 individual samples, global and global on-farm. Correlations and agreements between individual and pooled results were estimated with Spearman's correlation coefficient and Lin's concordance correlation coefficients, respectively. RESULTS: High correlation and agreement coefficients were found between the mean of individual FEC and the mean of FEC of the different pool sizes when considering all FEC obtained at D0 and D14. However, these parameters were lower for FECR calculation due to a poorer estimate of FEC at D14 from the faecal pools. When using FEC from pooled samples only at D0, higher correlation and agreement coefficients were found between FECR data, the better results being obtained with pools of 5 samples. Interestingly, FEC obtained on pooled samples by the portable FEC-kit on-farm showed high correlation and agreement with FEC obtained on individual samples in the laboratory. This field approach has to be validated on a larger scale to assess its feasibility and reliability. CONCLUSIONS: The present study highlights that the pooling strategy and the use of portable FEC-kits on-farm are rapid and cost-effective procedures for the assessment of GIN egg excretion and can be used cautiously for FECR calculation following the administration of anthelmintics in cattle.


Assuntos
Bovinos/parasitologia , Fezes/parasitologia , Infecções por Nematoides/veterinária , Contagem de Ovos de Parasitas/métodos , Animais , Anti-Helmínticos/uso terapêutico , Doenças dos Bovinos/tratamento farmacológico , Doenças dos Bovinos/parasitologia , Feminino , França , Itália , Infecções por Nematoides/diagnóstico , Contagem de Ovos de Parasitas/instrumentação , Kit de Reagentes para Diagnóstico , Reprodutibilidade dos Testes , Manejo de Espécimes/métodos
8.
Prev Vet Med ; 169: 104707, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31311641

RESUMO

Ethiopia is well known for its huge livestock resource that stands number one in Africa and 10th in the world. However, cattle production is constrained by inadequate nutrition, disease, lack of support services and inadequate information. This systematic review and meta-analysis of prevalence of C. bovis in Ethiopia aims to provide a national level prevalence of the parasite from reports conducted in different parts of the country. Due to the expected variation between studies, a random-effects meta-analysis was carried out using the total sample size and number of positives (effect size and standard error of the effect size). Individual study prevalence estimates ranged from 0% to 20% with an overall pooled prevalence of 7% (95% CI = 5%-8%). Studies weighted approximately equal with weights on individual studies ranging from 2% to 2.6% due to high heterogeneity between studies. The meta-analysis indicated that between-study variability was high (τ2 = 0.001; heterogeneity I2 = 99.20% with Heterogeneity chi-square = 4974.9 and, an associated p-value of 0.01). This parasite is indicated to be one of the causes of organ condemnation causing losses of million dollars annually in the country.


Assuntos
Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/parasitologia , Cisticercose/veterinária , Matadouros , Animais , Bovinos , Doenças dos Bovinos/economia , Cisticercose/economia , Cisticercose/epidemiologia , Etiópia/epidemiologia , Prevalência , Inquéritos e Questionários
9.
Prev Vet Med ; 169: 104695, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31311642

RESUMO

Resistance against macrocyclic lactones is emerging in Psoroptes ovis mites, the cause of psoroptic mange in sheep and cattle. Therefore, sustainable mange control approaches should be implemented to prevent or slow down resistance. To ensure a proper implementation of such approaches, it is crucial to understand the factors that may impede or facilitate adoption of these practices among farmers. A conceptual model that combines insights from the Theory of Planned Behaviour (TPB, Ajzen, 1991) - a theory that predicts human behaviour -, with insights from behavioural economics (Camerer, 2004; Samson, 2016) - a theory that assumes that behavioural biases or reasoning errors are pervasive in decision-making -, was developed to predict farmers' adoption intention. In particular, this paper examines how behavioural economics can influence farmers' beliefs related to sustainable mange control and through which pathways these biased beliefs can predict adoption intention. A cross-sectional survey study amongst 174 Belgian Blue cattle farmers has been conducted and Structural Equation Modelling was used for analyses. In particular, the model shows that farmers' positive attitudes towards a sustainable mange control method (attitude) and their perceptions of how others evaluate the sustainable control methods (subjective norms) more strongly predict adoption intention than perceived behavioural control. Additionally, the model shows that adoption intention is explained by the bandwagon bias -the belief that other farmers have a positive opinion about the control method-, and availability bias - farmers who have the belief that mange occurs often on their farm - through the determinants of TPB. Although this bandwagon bias influences farmers adoption intention, the rather low presence of availability bias might explain why adoption intention of a sustainable mange control method is limited. Next, retaining to the default treatment (default bias) influences farmers' belief that they are capable of implementing control methods on their farm (perceived behavioural control), while the belief that implementing a control method is perceived as a cost for their farm rather than being beneficial (loss aversion bias) negatively influences attitude and perceived behavioural control. We further discuss important implications that can incite farmers' adoption intention.


Assuntos
Fazendeiros/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Infestações por Ácaros/prevenção & controle , Infestações por Ácaros/psicologia , Análise de Variância , Animais , Bélgica , Bovinos , Doenças dos Bovinos/parasitologia , Doenças dos Bovinos/prevenção & controle , Doenças dos Bovinos/psicologia , Estudos Transversais , Comportamentos Relacionados com a Saúde , Humanos , Infestações por Ácaros/veterinária , Ovinos , Inquéritos e Questionários
10.
Onderstepoort J Vet Res ; 86(1): e1-e11, 2019 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-31291732

RESUMO

Fasciola spp. are the causative agents of fascioliasis in humans and livestock. Before the development of control and management measures, the geographical distribution of the species and patterns of infection must be considered. Because of difficulties in the phenotypic differentiation and morphometric classification of Fasciola spp., DNA molecular markers have become more useful for fluke differentiation and description of phylogenetic patterns. This study aimed to differentiate and describe the phylogenetic background of Fasciola spp. isolated from cattle slaughtered at three abattoirs in the Mpumalanga and KwaZulu-Natal provinces of South Africa. The cytochrome c oxidase I (COI) - FHCO1 (forward: 5'-TTGGTTTTTTGGGCATCCT-3') and FHCO1 (reverse: 5' -AGGCCACCACCAAATAAAAGA3') - marker was sequenced from 55 Fasciola flukes that were collected from abattoirs in catchment areas of the KwaZulu-Natal and Mpumalanga provinces. Fasciola hepatica was demonstrated to have 100% prevalence in KwaZulu-Natal and Mpumalanga (highveld), respectively, and 76% prevalence in the lowveld (Belfast area) of Mpumalanga. Two animals from the Belfast metapopulation were co-infected with both Fasciola gigantica and F. hepatica. DNA sequence analysis of all the isolates demonstrated a sequence conservation of 0.472, nucleotide diversity of 0.082 and Tajima's D of -1.100; however, it was not statistically significant (p > 0.05). Twenty-two haplotypes were identified, with 18 novel haplotypes being unique to the isolates from South Africa. Within the study samples, 12 haplotypes were isolated to a few individuals, with a haplotype diversity of 0.8957 indicating high genetic diversity. Principal coordinate analysis supported the clustering and distribution of the haplotypes, with 11.38% of the variation being attributed to coordinate 2 and 55.52% to coordinate 1. The distribution of Fasciola spp. has been demonstrated to be related to the distribution of the freshwater intermediate host snails, Lymnaea spp., as well as the relative altitude of the localities in South Africa. Information provided by this study serves as preliminary evidence for further studies on the mapping of the distribution of F. gigantica and F. hepatica in South Africa, which is key in designing control programmes for fascioliasis in humans and livestock.


Assuntos
Doenças dos Bovinos/epidemiologia , Complexo IV da Cadeia de Transporte de Elétrons/genética , Fasciola/isolamento & purificação , Fasciolíase/veterinária , Microbiologia de Alimentos , Matadouros , Animais , Bovinos , Doenças dos Bovinos/parasitologia , DNA de Helmintos/análise , Fasciola/classificação , Fasciola/genética , Fasciolíase/epidemiologia , Marcadores Genéticos , Filogenia , África do Sul/epidemiologia
11.
Vet Parasitol ; 271: 7-13, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31303208

RESUMO

In the current study, the egg hatch test (EHT) has been evaluated as an in vitro technique to detect albendazole (ABZ) resistance in Fasciola hepatica. The intra- and inter-assay variations of the EHT were measured by means of the coefficient of variation in different fluke isolates and over time; then, the results of the EHT were compared with the "gold standard" controlled efficacy test, which assesses the in vivo anthelmintic efficacy. The EHT was used later to evaluate the intra-herd variability regarding the level of ABZ resistance in calves infected by the same fluke isolate. Finally, several factors of the initial protocol were modified to improve the simplicity of the assay, including the incubation time of eggs with the drug and the use of eggs collected from faeces. The greatest uniformity between results within the assay and over time until 8 weeks after gallbladder collection (the deadline proposed for egg analysis) was obtained with an ABZ concentration of 0.5 µM. The length of exposure to ABZ was shown to be critical, as prolonged incubation (15 days) led to a change of ovicidal activity. The ABZ concentration of 0.5 µM is suggested as a possible discriminating dose to predict ABZ resistance, due to the close agreement between the results of the EHT at an ABZ concentration of 0.5 µM and those of the in vivo assays.


Assuntos
Albendazol/farmacologia , Doenças dos Bovinos/parasitologia , Fasciola hepatica/efeitos dos fármacos , Fasciolíase/veterinária , Testes de Sensibilidade Parasitária/métodos , Animais , Anti-Helmínticos/farmacologia , Bovinos , Doenças dos Bovinos/diagnóstico , Resistência a Medicamentos , Fasciolíase/diagnóstico , Fasciolíase/parasitologia , Fezes/parasitologia , Óvulo/efeitos dos fármacos , Fatores de Tempo
12.
Rev Bras Parasitol Vet ; 28(3): 514-517, 2019 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-31188946

RESUMO

Naegleria fowleri is a free-living amoeba commonly found in the environment, mainly in fresh water and soil. This protozoon is occasionally involved in cases of fatal central nervous system disease in humans and other animal species. We describe here a case of meningoencephalitis due to Naegleria fowleri in cattle, in southern Brazil. A four-year-old Angus cow presented a clinical history of initial mild neurological signs that progressed to paddling movements, opisthotonus and lateral recumbency after five days. This animal had been kept in an irrigated rice stubble paddock. Grossly, the main lesions consisted of multiple areas of malacia in the right olfactory bulb, piriform lobes, hippocampus, frontal lobe cortex and fornix, along with severe thickening of the mesencephalon and rhombencephalon leptomeninges. Microscopically, severe multifocal necrosuppurative and hemorrhagic meningoencephalitis associated with a large quantity of amoebic trophozoites was present. The latter were confirmed to be Naegleria spp., through immunohistochemistry. Based on the strong congruence with the histopathological data of known cases reported in the literature, a probable association with Naegleria fowleri was established. To our knowledge, this is only the second report of Naegleria fowleri-associated meningoencephalitis in cattle in South America, and it is the first in southern Brazil.


Assuntos
Doenças dos Bovinos/parasitologia , Infecções Protozoárias do Sistema Nervoso Central/veterinária , Naegleria fowleri/isolamento & purificação , Animais , Bovinos , Infecções Protozoárias do Sistema Nervoso Central/parasitologia , Feminino
13.
Parasitol Int ; 72: 101937, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31158501

RESUMO

Traditionally, Strongyloides nematode infecting cattle had been thought to be a single species, S. papillosus. Surprisingly, Eberhardt et al. in 2008 reported two, rather than one Strongyloides species infected cattle, with one being S. papillosus and the other S. vituli. However, there was no subsequent report to support their findings. In July 2018, a case of a sudden death of a calf believed to be due to heavy infection with S. papillosus at a dairy farm in Miyazaki Prefecture, Japan, was reported. One month after the initiation of a deworming program to prevent further sudden deaths, fecal specimens from 24 cattle housed in the same barn were examined. Eight samples were positive for Strongyloides eggs. For species determination, the nucleotide sequences of 18S rDNA (small subunit ribosomal DNA gene), rpl-10 (ribosomal protein L10 gene), and mitochondrial (mt) cox1 (cytochrome c oxidase subunit 1 gene) were obtained. Typing data for all three marker genes indicated the presence of both species, S. papillosus and S. vituli, in the fecal samples. To our knowledge, this study is the first to support the original report by Eberhardt et al. regarding the sympatric existence of S. papillosus and S. vituli in cattle, and to report the presence of S. vituli in Japan. Interestingly, phylogenetic analyses of both rpl-10 and mt cox1 sequences indicated a closer genetic relationship of S. vituli with S. venezuelensis (Strongyloides of rats) than with S. papillosus, shedding light on the speciation history of Strongyloides nematodes.


Assuntos
Doenças dos Bovinos/epidemiologia , Bovinos/parasitologia , Evolução Molecular , Strongyloides/genética , Estrongiloidíase/veterinária , Animais , Doenças dos Bovinos/parasitologia , Ciclo-Oxigenase 1/genética , DNA Ribossômico/genética , Fezes/parasitologia , Feminino , Japão , Filogenia , Strongyloides/isolamento & purificação , Estrongiloidíase/epidemiologia
14.
J Vet Diagn Invest ; 31(4): 656-660, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31179886

RESUMO

Sarcocystis spp. are causative agents of bovine eosinophilic myositis and/or myocarditis, which are chronic subclinical myopathies that are occasionally responsible for condemnation at slaughterhouses. Sarcocystis cruzi is a protozoan parasite of worldwide distribution transmitted by canids, most commonly associated with subclinical infection in cattle. Although S. cruzi infections can rarely lead to fatal systemic disease, fatal cardiac cases with confirmation of the etiologic diagnosis have not been reported, to our knowledge. We describe herein an unusual case of S. cruzi-induced fatal bovine eosinophilic myocarditis. A 22-mo-old, Holstein-Hereford heifer, in a group of 110 cattle on pasture, manifested growth retardation and died in February 2017. Autopsy revealed myriad yellow-green 1-3-mm coalescing foci, surrounded by fibrosis, affecting ~75% of the ventricular myocardium. Pulmonary edema, ascites, and hydrothorax were consistent with chronic congestive heart failure. Histology revealed severe eosinophilic, granulomatous, necrotizing myocarditis, with multinucleate giant cells, fibrosis, and mineralization. Numerous thin-walled protozoan cysts resembling Sarcocystis spp. were present in the necrotic foci and within the sarcoplasm of adjacent cardiomyocytes. PCR and sequencing of the 18S rRNA gene revealed 99.9-100% homology with S. cruzi. Sarcocystosis can be a rare cause of fatal myocarditis in cattle.


Assuntos
Doenças dos Bovinos/parasitologia , Miocardite/veterinária , Sarcocistose/veterinária , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Evolução Fatal , Feminino , Miocardite/parasitologia , Miocardite/patologia , Miocárdio/patologia , RNA de Protozoário/genética , RNA Ribossômico 18S/genética , Sarcocystis/genética , Sarcocystis/isolamento & purificação , Sarcocistose/epidemiologia , Uruguai
15.
Parasitol Res ; 118(7): 2079-2086, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31187226

RESUMO

Cryptosporidiosis of calves is caused by the enteroprotozoan Cryptosporidium spp. The disease results in intense diarrhea of calves associated with substantial economic losses in dairy farming worldwide. The aim of this study was to determine calf, herd, and within-herd Cryptosporidium prevalence and identify Cryptosporidium species and subtypes in calves with diarrhea in intensive dairy herds in central Argentina. A total of 1073 fecal samples were collected from 54 randomly selected dairy herds. Cryptosporidium-oocysts were isolated and concentrated from fecal samples using formol-ether and detected by light microscopy with the modified Ziehl-Neelsen technique. Overall prevalence of oocyst-excreting calves was found to be 25.5% (274/1073) (95% C.I. 22.9; 28.1%). Of the herds studied, 89% (48/54) included at least one infected calf, whereas within-herd prevalence ranged from the absence of infection to 57% (20/35). A highly significant association was found between the presence of diarrhea and C. parvum infection (χ2 = 55.89, p < 0.001). For species determination, genomic DNA isolated from oocyst-positive fecal samples was subjected to PCR-RFLP of the 18S rRNA gene resulting exclusively in Cryptosporidium parvum identification. C. parvum isolates of calves displaying diarrhea and high rate of excretion of oocysts were subtyped by PCR amplification and direct sequencing of the 60 kDa glycoprotein (GP60) gene. Altogether five GP60 subtypes, designated IIaA18G1R1, IIaA20G1R1, IIaA21G1R1, IIaA22G1R1, and IIaA24G1R1 were identified. Interestingly, IIaA18G1R1 and IIaA20G1R1 were predominant in calves with diarrhea and high infection intensity. Notably, IIaA24G1R1 represents a novel, previously unrecognized C. parvum subtype. The subtype IIaA18G1R1, frequently found in this study, is strongly implicated in zoonotic transmission. These results suggest that calves might be an important source for human cryptosporidiosis in Argentina.


Assuntos
Doenças dos Bovinos/epidemiologia , Criptosporidiose/epidemiologia , Cryptosporidium parvum/classificação , Cryptosporidium/classificação , Diarreia/veterinária , Animais , Argentina/epidemiologia , Bovinos , Doenças dos Bovinos/parasitologia , Criptosporidiose/parasitologia , Criptosporidiose/transmissão , Cryptosporidium/genética , Cryptosporidium/isolamento & purificação , Cryptosporidium parvum/genética , Cryptosporidium parvum/isolamento & purificação , Diarreia/epidemiologia , Diarreia/parasitologia , Fezes/parasitologia , Feminino , Glicoproteínas/genética , Humanos , Oocistos , Reação em Cadeia da Polimerase/veterinária , Polimorfismo de Fragmento de Restrição , Prevalência , Zoonoses
16.
Parasit Vectors ; 12(1): 324, 2019 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-31248445

RESUMO

BACKGROUND: The zoonotic tapeworm Taenia saginata, although causing only minor discomfort in humans, is responsible for considerable economic losses in the livestock sector due to condemnation or downgrading of infected beef carcasses. An overview of current knowledge on the distribution and prevalence of this parasite in West and Central Africa is lacking. METHODS: We conducted a systematic review, collecting information on published and grey literature about T. saginata taeniosis and bovine cysticercosis from 27 countries/territories in West and Central Africa, published between January 1st, 1990 and December 31st, 2017. RESULTS: The literature search retrieved 1672 records, of which 51 and 45 were retained for a qualitative and quantitative synthesis, respectively. Non-specified human taeniosis cases were described for Nigeria, Cameroon, Senegal, Burkina Faso, Democratic Republic Congo, Guinea, and Ivory Coast (seven out of 27 countries/territories), while T. saginata taeniosis specifically was only reported for Cameroon. Most prevalence estimates for taeniosis ranged between 0-11%, while three studies from Nigeria reported prevalence estimates ranging between 23-50%. None of the studies included molecular confirmation of the causative species. The presence of bovine cysticercosis was reported for Benin, Burkina Faso, Cameroon, Central African Republic, Chad, Democratic Republic Congo, Ghana, Guinea, Ivory Coast, Mali, Niger, Nigeria, Senegal, and Tristan da Cunha (14 out of 27 countries/territories). Prevalence estimates ranged between 0-29%. CONCLUSIONS: Our systematic review has revealed that human taeniosis and bovine cysticercosis are seriously understudied in West and Central Africa. The high prevalence estimates of both conditions suggest an active dissemination of this parasite in the region, calling for a concerted One Health action from public health, veterinary health and food surveillance sectors.


Assuntos
Doenças dos Bovinos/epidemiologia , Cisticercose/veterinária , Gado/parasitologia , Taenia saginata/isolamento & purificação , Teníase/veterinária , África Central/epidemiologia , África Ocidental/epidemiologia , Animais , Bovinos , Doenças dos Bovinos/parasitologia , Cisticercose/epidemiologia , Humanos , Prevalência , Saúde Pública , Carne Vermelha/parasitologia , Teníase/epidemiologia
17.
Parasitol Res ; 118(8): 2431-2435, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31243541

RESUMO

Bovine piroplasmosis is a tick-borne disease caused by apicomplexan hemoparasites of the genera Theileria and Babesia. This study was carried out to assess the presence and frequency of piroplasm parasites in apparently healthy cattle in Kyrgyzstan. A total of 454 blood samples were collected from animals of various ages in eight villages located in the Chu valley and around the Lake Issyk Kul. The hypervariable V4 region of the 18S ribosomal RNA (rRNA) gene was amplified with a set of primers specific targeting members of the genera Theileria and Babesia. Amplified PCR products were hybridized onto a membrane to which generic and species-specific oligonucleotide probes were covalently linked. The results revealed the presence of three piroplasm species (Theileria orientalis, Babesia major, Theileria annulata). Theileria orientalis was the most prevalent species (32.8%; CI 28.5-37.3). Babesia major was the only species of Babesia found in any of the samples (1.3%; CI 0.5-2.8). The co-existence of Theileria annulata and T. orientalis was detected in nine animals (1.9%; CI 0.9-3.7). BLAST search revealed that the Theileria sequences shared 100% identity with the recently reported sequences for T. buffeli and T. annulata. The sequence of B. major was also 100% identical to an existing B. major sequence. This molecular survey provides important epidemiological data for control of bovine piroplasmosis caused by T. orientalis, B. major, and T. annulata in Kyrgyzstan.


Assuntos
Babesia/genética , Babesiose/parasitologia , Doenças dos Bovinos/parasitologia , Theileria/genética , Theileriose/parasitologia , Animais , Babesia/isolamento & purificação , Babesia/fisiologia , Babesiose/sangue , Bovinos , Doenças dos Bovinos/sangue , DNA de Protozoário/genética , Quirguistão , Reação em Cadeia da Polimerase , RNA Ribossômico 18S/genética , Theileria/isolamento & purificação , Theileria/fisiologia , Theileriose/sangue
18.
Rev Bras Parasitol Vet ; 28(2): 333-337, 2019 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-31188945

RESUMO

The objectives of this study were to describe occurrences of Rhabditis spp. causing parasitic otitis in dairy cattle of Gir breed in the state of Espírito Santo, southeastern Brazil, and to evaluate the biological control of this nematode using the nematophagous fungi Duddingtonia flagrans (AC001) and Monacrosporium thaumasium (NF34). After nematode detection and collection, three groups were formed: two groups that were treated, respectively, with the fungal isolates; and a control group, without fungus. The treatments were as follows: (a) Petri dishes containing the culture medium 2% water agar (WA) + 250 nematodes + AC001; (b) Petri dishes containing 2% WA + 250 nematodes + NF34; and (c) Petri dishes containing only 2% WA + 250 nematodes. After seven days at 27 °C the treatments with fungi were able to capture and destroy the nematodes, with percentages of 82.0% (AC001) and 39.0% (NF34) in relation to the control group. The results demonstrate the occurrence of Rhabditis spp. after animals physical examination and that there was efficacy of the in vitro predatory activity of both fungal isolates. Thus, these results are important because they can assist in future in vivo control of this nematode in cattle.


Assuntos
Doenças dos Bovinos/parasitologia , Otite/veterinária , Controle Biológico de Vetores/métodos , Infecções por Rhabditida/veterinária , Rhabditoidea/microbiologia , Animais , Ascomicetos/fisiologia , Bovinos , Duddingtonia/fisiologia , Otite/parasitologia , Otite/terapia , Infecções por Rhabditida/terapia
19.
Rev Bras Parasitol Vet ; 28(2): 215-220, 2019 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-31215607

RESUMO

Our objective was to identify the direct and indirect presence of Neospora caninum in dairy cattle and their aborted fetuses from Lima, Peru. A total 219 blood samples obtained from dairy cattle with records of spontaneous abortion were collected to detect antibodies against N. caninum in serum with indirect ELISA and search for risk-factor associations. 68 fetal aborted tissue samples of these cows were analyzed by PCR, indirect ELISA and histopathology assay to detect N. caninum presence. The prevalence ratio (PR) and 95% confidence intervals (CI) were estimated. Univariate analysis was performed using the chi-squared test. Among the 68 aborted fetuses collected, 10 (15%) were positive in at least two diagnostic tests. Among 219 serum samples, 46.6% (95% CI: 40.0%-53.3%) were positive. Cows with 4 years or older (PR: 7.10; 95% CI: 4.89-10.67) and multiparous (PR: 1.76; 95% CI: 1.11-2.80) were found to be more likely to possess N. caninum antibodies. This study detects presence of N. caninum in dairy cattle and their aborted fetus from Lima valley, suggesting biosecurity management improve to neosporosis control.


Assuntos
Aborto Animal/epidemiologia , Anticorpos Antiprotozoários/sangue , Doenças dos Bovinos/epidemiologia , Coccidiose/veterinária , Neospora , Aborto Animal/parasitologia , Animais , Bovinos , Doenças dos Bovinos/parasitologia , Coccidiose/complicações , Coccidiose/epidemiologia , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Neospora/genética , Neospora/imunologia , Peru/epidemiologia , Reação em Cadeia da Polimerase/veterinária , Gravidez , Fatores de Risco , Estudos Soroepidemiológicos
20.
Rev Bras Parasitol Vet ; 28(2): 245-257, 2019 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-31215610

RESUMO

This is a cross-sectional study to assess the presence of antibodies in ruminants against selected pathogens associated with reproductive disorders in cattle in four Brazilian states, including the zoonotic agent Coxiella burnetii. The used tests were Virus Neutralization Assay for IBR and BVD, Microscopic Agglutination Test for Leptospira spp., Indirect Fluorescent Antibody Test (IFAT) for C. burnetii and Toxoplasma gondii, and Enzyme-Linked Immunosorbent Assay for Neospora caninum and Trypanosoma vivax. Seropositivity for C. burnetii was 13.7% with titers from 128 to 131,072; 57.8% for BoHV-1, with titers between 2 and 1,024; 47.1% for BVDV-1a, with titers from 10 to 5,120; 89.2% for N. caninum; 50% for T. vivax; and 52.0% for Leptospira spp., with titers between 100 to 800 (the following serovars were found: Tarassovi, Grippotyphosa, Canicola, Copenhageni, Wolffi, Hardjo, Pomona and Icterohaemorrhagiae); 19.6% for T. gondii with titer of 40. This is the first study that has identified C. burnetii in cattle associated with BoHV and BVDV, N. caninum, Leptospira spp., T. gondii and T. vivax. Thus, future studies should be conducted to investigate how widespread this pathogen is in Brazilian cattle herds.


Assuntos
Doença das Mucosas por Vírus da Diarreia Viral Bovina/complicações , Doenças dos Bovinos/epidemiologia , Coccidiose/veterinária , Leptospirose/veterinária , Febre Q/veterinária , Toxoplasmose Animal/complicações , Tripanossomíase Africana/veterinária , Aborto Animal , Testes de Aglutinação , Animais , Doença das Mucosas por Vírus da Diarreia Viral Bovina/diagnóstico , Doença das Mucosas por Vírus da Diarreia Viral Bovina/epidemiologia , Brasil/epidemiologia , Bovinos , Doenças dos Bovinos/microbiologia , Doenças dos Bovinos/parasitologia , Doenças dos Bovinos/virologia , Coccidiose/complicações , Coccidiose/diagnóstico , Coccidiose/epidemiologia , Coxiella burnetii/imunologia , Estudos Transversais , Vírus da Diarreia Viral Bovina/imunologia , Endometrite/etiologia , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Técnica Indireta de Fluorescência para Anticorpo/veterinária , Infertilidade Feminina/etiologia , Leptospira/imunologia , Leptospirose/complicações , Leptospirose/diagnóstico , Leptospirose/epidemiologia , Neospora/imunologia , Febre Q/complicações , Febre Q/diagnóstico , Febre Q/epidemiologia , Estudos Soroepidemiológicos , Toxoplasma/imunologia , Toxoplasmose Animal/diagnóstico , Trypanosoma vivax/imunologia , Tripanossomíase Africana/complicações , Tripanossomíase Africana/diagnóstico , Tripanossomíase Africana/epidemiologia
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