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1.
Vet Parasitol Reg Stud Reports ; 52: 101056, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38880573

RESUMO

This study focuses on the occurrence, identification, and molecular characterization of Eimeria species causing coccidiosis in cattle in the Kashmir Valley, India. Coccidiosis, caused by apicomplexan parasites of the genus Eimeria, poses a significant threat to global cattle farming. Conventional techniques for identification, which rely on the morphology of sporulated oocysts, have drawbacks, leading to the adoption of molecular techniques to accurately delimit species. A total of 190 cattle were sampled in nine farms and parasitological examination revealed an occurrence of 45.7% for Eimeria spp. Molecular analysis using PCR and sequencing identified three predominant species: E. zuernii, E. alabamensis, and E. bovis. The study highlights the widespread occurrence of these species globally, as supported by previous research conducted in Bangladesh, Austria, Egypt, and Brazil. The phylogenetic analysis based on internal transcribed spacer (ITS-1) gene sequences revealed distinct clusters for E. zuernii and E. bovis, while E. alabamensis formed a separate clade. The genetic diversity and phylogenetic connections provide insights into the evolutionary relationships among these Eimeria species. This study contributes valuable information for understanding the epidemiology and genetic diversity of cattle coccidiosis in the Kashmir Valley, emphasizing the importance of molecular characterization for accurate species identification.


Assuntos
Doenças dos Bovinos , Coccidiose , Eimeria , Variação Genética , Animais , Bovinos , Coccidiose/epidemiologia , Coccidiose/parasitologia , Coccidiose/veterinária , Eimeria/classificação , Eimeria/genética , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/parasitologia , Índia/epidemiologia , Filogenia , Reação em Cadeia da Polimerase , DNA Espaçador Ribossômico/genética
2.
Ticks Tick Borne Dis ; 15(5): 102363, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38852540

RESUMO

Among cattle, Bos taurus breeds and their crosses are more sensitive to tick infestations than Bos indicus breeds that are more resistant to infestation and more adaptable to tropical climates. The presence of susceptible individuals in herds and inadequate tick control lead to direct and indirect losses in the meat production chain, in addition to increased mortality due to cattle tick fever. The objective of this study was to describe, compare and rank the sensitivity of different breeds of stabled cattle to the tick Rhipicephalus microplus and to present, as an innovative result, a scale called the Tick Ruler. Secondary data on the number of retrieved engorged females, engorged female ticks' weight, egg mass weight and number of larvae were extracted from research reports of experiments conducted over 18 years with eight breeds to describe and report the sensitivity of the breeds to artificial infestation by R. microplus larvae. For analyses, the recovery rate of engorged female ticks and the percentile of dispersion of individuals in their respective races were calculated, and comparison of these percentiles between races was performed. The ranking of the percentiles resulted in the organization of the breeds by their susceptibility to R. microplus; we call this scale the "Tick Ruler." The ruler is a simple, easy-to-understand tool that can be used by technicians and producers to evaluate the tick sensitivity of a breed of interest and can assist producers in decision-making to find a balance between increased production gains and the risk of economic losses depending on the breed composition in a cattle herd.


Assuntos
Doenças dos Bovinos , Larva , Rhipicephalus , Infestações por Carrapato , Animais , Rhipicephalus/fisiologia , Rhipicephalus/genética , Bovinos , Infestações por Carrapato/veterinária , Infestações por Carrapato/parasitologia , Feminino , Doenças dos Bovinos/parasitologia , Larva/crescimento & desenvolvimento , Larva/fisiologia , Cruzamento
3.
Vet Parasitol Reg Stud Reports ; 52: 101057, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38880570

RESUMO

Cryptosporidium is one of the most important enteric diarrhoeal parasites that infect humans and animals worldwide. The current study investigated the occurrence and risk factors associated with Cryptosporidium infection in ruminants aged ≤6 months in Monze, Mumbwa, and Lusaka districts of Zambia. Faecal samples were collected from 328 calves, 190 lambs, and 245 goat kids and analysed for Cryptosporidium oocysts using modified Ziehl Neelsen staining. A closed structured questionnaire was used to obtain epidemiological characteristics and potential risk factors for Cryptosporidium infection. The overall occurrence of Cryptosporidium was 7.9% (60/763), while that in calves, lambs and goat kids was 14.5% (47/328), 5.3% (10/190), and 1.2% (3/245) respectively. Watery/pasty stool and sampling during the rainy season were independently associated with increased risk of infection. In calves, the odds of infection increased during the rainy season, while daily kraal cleaning reduced the infection risk. Lambs showed increased odds of infection with pasty/watery stool and male sex, whereas the wearing of protective clothing by handlers significantly reduced the risk. There were district variations in infection occurrence with Mumbwa district having higher prevalence. The findings of this study show that livestock in Zambia continue to be frequently infected with Cryptosporidium. Protective measures and appropriate farm cleanliness should be implemented in control of this infection. Regional and host-species-specific variations emphasize the need for targeted interventions. These findings, therefore, contribute to effective strategies for Cryptosporidium control, promoting good livestock health and management.


Assuntos
Doenças dos Bovinos , Criptosporidiose , Cryptosporidium , Fezes , Doenças das Cabras , Cabras , Doenças dos Ovinos , Animais , Criptosporidiose/epidemiologia , Criptosporidiose/parasitologia , Zâmbia/epidemiologia , Ovinos , Fatores de Risco , Doenças das Cabras/epidemiologia , Doenças das Cabras/parasitologia , Cryptosporidium/isolamento & purificação , Doenças dos Ovinos/epidemiologia , Doenças dos Ovinos/parasitologia , Fezes/parasitologia , Masculino , Bovinos , Feminino , Prevalência , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/parasitologia , Estações do Ano , Gado/parasitologia
4.
Vet Parasitol Reg Stud Reports ; 52: 101050, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38880579

RESUMO

Species belonging to the family Paramphistomidae Fischoeder, 1901, commonly known as "rumen flukes", are a group of parasites frequently related to Brazilian livestock production. They inhabit the digestive tract of ruminants and have recognized pathogenicity during the early stages of infection, which can be responsible for economic losses. These trematodes are often associated with Southern Brazil, a region heavily focused on animal farming, which also makes it ideal for the life cycle of paramphistomes. Despite their aforementioned importance, studies regarding their distribution, molecular taxonomy and biology are still scarce in the country. In the present study, rumen flukes collected from cattle (n = 22) and sheep (n = 3) from 9 batches of ruminants from the cities of Jaguarão, Pelotas and Rio Grande, state of Rio Grande do Sul, Brazil, between May and July 2022, were subjected to morphological and molecular study. The microscopic analysis of histological and manual cuts revealed diagnostical traits compatible with Paramphistomum leydeni Näsmark, 1937, including the presence of tegumental papillae, pharynx of the liorchis type and acetabulum of the leydeni type. Molecular data corroborated the morphological identification, with ITS-2 and cox-1 sequences here obtained presenting 100% and 96.8-99.8% similarity, respectively, to P. leydeni samples previously characterized in different countries from Asia, Europe, and South America. Intensity of infection ranged from 5 to 458 and 1 to3 specimens of P. leydeni in sampled cattle and sheep, respectively. The present study contributes to a better understanding of the taxonomy of the flukes involved in cattle and sheep paramphistomosis in Brazil, suggesting that P. leydeni could be the main paramphistome species found in ruminants in the studied region.


Assuntos
Doenças dos Bovinos , Paramphistomatidae , Doenças dos Ovinos , Infecções por Trematódeos , Animais , Brasil/epidemiologia , Bovinos , Ovinos , Infecções por Trematódeos/veterinária , Infecções por Trematódeos/parasitologia , Infecções por Trematódeos/epidemiologia , Doenças dos Bovinos/parasitologia , Doenças dos Bovinos/epidemiologia , Doenças dos Ovinos/parasitologia , Doenças dos Ovinos/epidemiologia , Paramphistomatidae/genética , Paramphistomatidae/classificação , Paramphistomatidae/isolamento & purificação , Rúmen/parasitologia , Filogenia
5.
Parasit Vectors ; 17(1): 245, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38824598

RESUMO

BACKGROUND: Bovine babesiosis is caused by infection with the protozoal parasite Babesia bovis, which is transmitted by Rhipicephalus (Boophilus) spp. It can cause mortality rates up to 90% in immunologically naive Bos taurus cattle. In south Texas, R. (B.) microplus is known to infest nilgai antelope (Boselaphus tragocamelus); however, their susceptibility to infection with B. bovis and their role in the transmission of the parasite remain unknown. In this study, we challenged nilgai antelope with B. bovis and evaluated their susceptibility to infection. METHODS: Nilgai were needle inoculated with ≈108 B. bovis-parasitized erythrocytes (merozoites) or a homogenate of B. bovis-infected larval ticks (sporozoite) delivered intravenously. Bos taurus beef calves were inoculated in parallel, as this strain of B. bovis is lethal to cattle. Temperature and hematocrit were monitored daily over the course of each study, and whole blood was collected for molecular [polymerase chain reaction (PCR)] and serological [indirect enzyme-linked immunosorbent assay (ELISA)] diagnostic evaluation. Histological sections of nilgai cerebral tissue were examined for evidence of infection. Recipient bovine calves were sub-inoculated with blood from nilgai challenged with either stage of the parasite, and they were monitored for clinical signs of infection and evaluated by a PCR diagnostic assay. Red blood cells (RBCs) from prechallenged nilgai and B. taurus beef cattle were cultured with an in vitro B. bovis merozoite culture to examine colonization of the RBCs by the parasite. RESULTS: Nilgai did not display clinical signs of infection upon inoculation with either the merozoite or sporozoite stage of B. bovis. All nilgai were PCR-negative for the parasite, and they did not develop antibodies to B. bovis. No evidence of infection was detected in histological sections of nilgai tissues, and in vitro culture analysis indicated that the nilgai RBCs were not colonized by B. bovis merozoites. Cattle subinoculated with blood from challenged nilgai did not display clinical signs of infection, and they were PCR-negative up to 45 days after transfer. CONCLUSIONS: Nilgai do not appear to be susceptible to infection with a strain of B. bovis that is lethal to cattle. Tick control on these alternative hosts remains a critical priority, especially given their potential to disseminate ticks over long distances.


Assuntos
Antílopes , Babesia bovis , Babesiose , Animais , Babesia bovis/genética , Babesia bovis/patogenicidade , Babesia bovis/isolamento & purificação , Babesia bovis/imunologia , Babesiose/parasitologia , Bovinos , Antílopes/parasitologia , Doenças dos Bovinos/parasitologia , Eritrócitos/parasitologia , Texas , Virulência , Rhipicephalus/parasitologia , Feminino , Reação em Cadeia da Polimerase
6.
Parasitol Res ; 123(6): 232, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38847882

RESUMO

This work evaluated if strategic control based on no more than three or four annual treatments is useful to control Rhipicephalus microplus infestations on cattle when it is applied to intensive rotational grazing and silvopastoral systems with high stocking rates in subtropical areas. In the intensive rotational grazing system, three annual treatments with chemical acaricides were applied on cattle in two different schemes: between spring and early summer and from late winter and late spring. Strategic control based on three treatments with chemical acaricides from late winter to late spring plus an additional fourth treatment in summer was tested in the silvopastoral system. In the intensive rotational grazing systems, the control schemes allow to reach a significant reduction in the tick load on cattle considering a time interval from spring to autumn. However, the efficacy levels were not high enough in some specific moments, namely, the tick counts of summer and autumn (there were not significant differences between treated and control groups). The scheme evaluated in the silvopastoral grazing system yielded better results than those tested for the intensive rotational system, because significant differences in tick load between treated and control groups were observed in all post-treatment counts and when the analysis was performed for the whole study period. However, values of efficacy in the count-by-count comparison were disparate, ranging from 64.1 to 99.7. Although the efficacy values obtained in the silvopastoral system were better than those of the rotational grazing systems, the total tick load on treated cattle in autumn was not low enough (mean abundance values 25.14 and 38.14). Ticks were more evenly distributed among hosts in late summer and autumn than in spring or early summer, where few hosts carry most of the ticks. Some management strategies as intensive rotational systems or silvopastoral structures can lead to a more efficient forage use, but they imply greater tick challenge than in extensive grazing systems. In these situations, the schemes of strategic control bases on three or four annual treatments should be complemented with additional tactical treatments in late summer or autumn.


Assuntos
Doenças dos Bovinos , Rhipicephalus , Estações do Ano , Controle de Ácaros e Carrapatos , Infestações por Carrapato , Animais , Bovinos , Rhipicephalus/fisiologia , Infestações por Carrapato/veterinária , Infestações por Carrapato/prevenção & controle , Infestações por Carrapato/parasitologia , Doenças dos Bovinos/parasitologia , Doenças dos Bovinos/prevenção & controle , Controle de Ácaros e Carrapatos/métodos , Acaricidas , Criação de Animais Domésticos/métodos
7.
Vet Parasitol ; 329: 110211, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38772086

RESUMO

Ticks, particularly Rhipicephalus annulatus, pose significant threats to livestock, causing economic losses and transmitting various infectious diseases. This study aimed to evaluate the potential acaricidal properties of garlic oil and its nanoemulsion against ticks infesting cattle, Rhipicephalus annulatus through the evaluation of mortality rate and morphological changes of the treated ticks. The study also included prevalence, risk factors, and molecular confirmation of tick species. Genetic characterization confirmed the identity of R. annulatus. Our results revealed a high prevalence of R. annulatus (46.9%) with a higher risk in male cattle (50%) than females (44.9%) and a nonsignificant high infection (49.1%) in animals ≤ 1 year old. The acaricidal efficiency of garlic oil and its nanoemulsion was concentration and time-dependent. The high concentration of garlic oil (20 mg/L) induced complete mortality within 48 hours. The nanoemulsion formulation enhanced efficacy, particularly at 5 mg/L, which exhibited rapid and substantial acaricidal activity. Scanning electron microscopy revealed morphological alterations induced by garlic oil and its nanoemulsion, including changes to the anterior capitulum, dorsal, and ventral cuticles. The study contributes to the exploration of effective, safe, and eco-friendly alternatives for tick control. Further research is warranted to validate their efficacy under diverse conditions and assess practical strategies.


Assuntos
Acaricidas , Doenças dos Bovinos , Emulsões , Rhipicephalus , Infestações por Carrapato , Animais , Acaricidas/farmacologia , Infestações por Carrapato/veterinária , Infestações por Carrapato/parasitologia , Infestações por Carrapato/tratamento farmacológico , Infestações por Carrapato/prevenção & controle , Doenças dos Bovinos/parasitologia , Doenças dos Bovinos/tratamento farmacológico , Feminino , Bovinos , Masculino , Rhipicephalus/efeitos dos fármacos , Sulfetos/farmacologia , Sulfetos/uso terapêutico , Compostos Alílicos/farmacologia , Alho/química
8.
Vet Parasitol ; 329: 110187, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38728835

RESUMO

This guideline is aimed at those who are involved in the assessment of anthelmintic efficacy in ruminant livestock species (bovine, ovine and caprine). The intent is to provide a framework that can be adopted worldwide for the testing of anthelmintics in ruminants, such that studies carried out in different countries can be compared and thereby unnecessary duplication can be reduced. Recommendations are made for the selection, housing and feeding of study animals, the type of studies required, the method used to conduct those studies, the assessment of results and the standards for defining anthelmintic efficacy.


Assuntos
Anti-Helmínticos , Cabras , Ruminantes , Animais , Anti-Helmínticos/uso terapêutico , Bovinos , Ovinos , Ruminantes/parasitologia , Doenças dos Ovinos/tratamento farmacológico , Doenças dos Ovinos/parasitologia , Doenças das Cabras/tratamento farmacológico , Doenças das Cabras/parasitologia , Helmintíase Animal/tratamento farmacológico , Helmintíase Animal/parasitologia , Doenças dos Bovinos/tratamento farmacológico , Doenças dos Bovinos/parasitologia
9.
Exp Parasitol ; 262: 108769, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38735519

RESUMO

The aim of the present study was to validate methods of stool sample conservation for the egg hatch test (EHT). This study involved the use of a bovine naturally infected predominantly by Cooperia spp. and one equine naturally infected predominantly by cyathostomins characterized as susceptible to benzimidazoles in the EHT. Fecal samples were submitted to three treatments: aerobic methods (anaerobic storage in plastic bottles, anaerobic storage in vacuum-sealed bags or aerobic storage in plastic bags), under two temperature conditions (room temperature and refrigeration) analyzed at four different assessment times (48, 72, 96 and 120 h). As the standard test, an assay was also performed within 3 h. The tests were performed in triplicate for each drug concentration and with three experimental repetitions at one-week intervals. Two criteria were used for the storage methods: hatchability in the negative control group and sensitivity of the eggs to thiabendazole, comparing the EC50 and 95% confidence interval for each treatment to those of the standard test and the other repetitions. Bovine samples can be stored for up to 96 h and refrigerated vacuum storage can be used, ensuring hatchability of the negative control and sensitivity of the eggs to thiabendazole. For equine samples, no forms of storage were indicated due to the variation among the repetitions and the reduction in the sensitivity of the eggs to thiabendazole, which could result in a false positive detection of resistance.


Assuntos
Fezes , Óvulo , Animais , Bovinos , Fezes/parasitologia , Cavalos/parasitologia , Óvulo/efeitos dos fármacos , Tiabendazol/farmacologia , Manejo de Espécimes/métodos , Manejo de Espécimes/veterinária , Temperatura , Anti-Helmínticos/farmacologia , Contagem de Ovos de Parasitas/veterinária , Contagem de Ovos de Parasitas/métodos , Nematoides/efeitos dos fármacos , Nematoides/isolamento & purificação , Doenças dos Bovinos/parasitologia , Doenças dos Bovinos/diagnóstico
10.
Parasitol Res ; 123(5): 202, 2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38703234

RESUMO

Theileria orientalis, the causal agent of oriental theileriosis, is known to cause mild disease in cattle and buffalo across the world. Recently, different genotypes of T. orientalis have emerged as pathogenic, causing high reported morbidity in cattle. This study focuses on investigating three suspected outbreaks of oriental theileriosis that resulted in fatalities among crossbred and indigenous bulls in Karnataka, India. Examination of blood smears revealed the presence of T. orientalis piroplasms within erythrocytes. The genetic characterization of T. orientalis was conducted by targeting specific markers, including the mpsp gene, p23 gene, and ribosomal DNA markers (18S rRNA gene, ITS-1, and ITS-2). Analysis based on the 18S rRNA gene unveiled the presence of both Type A and Type E genotypes of T. orientalis in the outbreaks. The mpsp gene-based analysis identified genotype 7 of T. orientalis in crossbred cows, whereas genotype 1 (Chitose B) was found to be present in indigenous bulls. Haplotype network analysis based on the mpsp gene revealed the presence of 39 distinct haplotypes within the 12 defined genotypes of T. orientalis with a high haplotype diversity of 0.9545 ± 0.017. Hematological and biochemical analysis revealed a decrease in calcium, hemoglobin levels, red blood cell counts, and phosphorus. This study constitutes the initial documentation of a clinical outbreak of oriental theileriosis in indigenous bulls with genotype 1 (Chitose 1B). Substantial epidemiological investigations are imperative to gain a comprehensive understanding of the geographical distribution of distinct genotypes and the diverse clinical manifestations of the disease across various hosts.


Assuntos
Surtos de Doenças , Variação Genética , Genótipo , RNA Ribossômico 18S , Theileria , Theileriose , Animais , Theileria/genética , Theileria/classificação , Bovinos , Theileriose/epidemiologia , Theileriose/parasitologia , Índia/epidemiologia , Surtos de Doenças/veterinária , RNA Ribossômico 18S/genética , Masculino , DNA de Protozoário/genética , Filogenia , Doenças dos Bovinos/parasitologia , Doenças dos Bovinos/epidemiologia , Análise de Sequência de DNA , Proteínas de Protozoários/genética , DNA Espaçador Ribossômico/genética , DNA Ribossômico/genética , DNA Ribossômico/química
11.
Parasitol Res ; 123(5): 207, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38713234

RESUMO

Biomarkers are specific molecular, histological, or physiological characteristics of normal or pathogenic biological processes and are promising in the diagnosis of gastrointestinal nematodes (GINs). Although some biomarkers have been validated for infection by Ostertagia sp. in cattle raised in temperate regions, there is a lack of information for tropical regions. The aim of this project was to assess potential biomarkers and validate the most promising. In the first study, 36 bovines (Nelore breed) naturally infected by GINs were distributed into two groups: infected (not treated with anthelmintic) and treated (treated with fenbendazole on days 0, 7, 14, 21, 28, 42, and 56). The variables of interest were live weight, fecal egg count, hemogram, serum biochemical markers, phosphorus, gastrin, and pepsinogen. In the second step, pepsinogen was assessed in cattle of the Nelore breed distributed among three groups: infected (not treated with anthelmintic), MOX (treated with moxidectin), and IVM + BZD (treated with ivermectin + albendazole). In the first study, no difference between groups was found for weight, albumin, hematocrit (corpuscular volume [CV]), erythrocytes, or hemoglobin. Negative correlations were found between pepsinogen and both CV and albumin, and albumin was negatively correlated with the percentage of Haemonchus sp. in the fecal culture. Among the biomarkers, only pepsinogen differentiated treated and infected (beginning with the 28th day of the study). In the second study, a reduction in pepsinogen was found after anthelmintic treatment. Therefore, pepsinogen is a promising biomarker of worms in cattle naturally infected by the genera Haemonchus and Cooperia in tropical areas.


Assuntos
Biomarcadores , Doenças dos Bovinos , Fezes , Infecções por Nematoides , Clima Tropical , Animais , Bovinos , Doenças dos Bovinos/parasitologia , Doenças dos Bovinos/tratamento farmacológico , Biomarcadores/sangue , Infecções por Nematoides/veterinária , Infecções por Nematoides/parasitologia , Infecções por Nematoides/tratamento farmacológico , Fezes/parasitologia , Contagem de Ovos de Parasitas , Anti-Helmínticos/uso terapêutico , Nematoides/isolamento & purificação , Nematoides/classificação , Nematoides/efeitos dos fármacos , Gastroenteropatias/parasitologia , Gastroenteropatias/veterinária , Enteropatias Parasitárias/veterinária , Enteropatias Parasitárias/parasitologia , Fenbendazol/uso terapêutico
12.
Parasitol Res ; 123(5): 210, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38743097

RESUMO

Fasciola gigantica is a widespread parasite that causes neglected disease in livestock worldwide. Its high transmissibility and dispersion are attributed to its ability to infect intermediate snail hosts and adapt to various mammalian definitive hosts. This study investigated the variation and population dynamics of F. gigantica in cattle, sheep, and goats from three states in Sudan. Mitochondrial cytochrome c oxidase subunit I (COI) and NADH dehydrogenase subunit 1 (ND1) genes were sequenced successfully to examine intra and interspecific differences. ND1 exhibited higher diversity than COI, with 15 haplotypes and 10 haplotypes, respectively. Both genes had high haplotype diversity but low nucleotide diversity, with 21 and 11 polymorphic sites for ND1 and COI, respectively. Mismatch distribution analysis and neutrality tests revealed that F. gigantica from different host species was in a state of population expansion. Maximum likelihood phylogenetic trees and median networks revealed that F. gigantica in Sudan and other African countries had host-specific and country-specific lineages for both genes. The study also indicated that F. gigantica-infected small ruminants were evolutionarily distant, suggesting deep and historical interspecies adaptation.


Assuntos
Complexo IV da Cadeia de Transporte de Elétrons , Fasciola , Fasciolíase , Variação Genética , Cabras , Haplótipos , NADH Desidrogenase , Filogenia , Dinâmica Populacional , Animais , Sudão/epidemiologia , Fasciola/genética , Fasciola/classificação , Fasciola/isolamento & purificação , Fasciolíase/veterinária , Fasciolíase/parasitologia , Fasciolíase/epidemiologia , Ovinos/parasitologia , Cabras/parasitologia , Bovinos , NADH Desidrogenase/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Doenças das Cabras/parasitologia , Doenças das Cabras/epidemiologia , Ruminantes/parasitologia , Doenças dos Ovinos/parasitologia , Doenças dos Ovinos/epidemiologia , Doenças dos Bovinos/parasitologia , Doenças dos Bovinos/epidemiologia , Análise de Sequência de DNA
13.
Front Immunol ; 15: 1380660, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38720894

RESUMO

Introduction: Babesia bovis, a tick-borne apicomplexan parasite causing bovine babesiosis, remains a significant threat worldwide, and improved and practical vaccines are needed. Previous studies defined the members of the rhoptry associated protein-1 (RAP-1), and the neutralization-sensitive rhoptry associated protein-1 related antigen (RRA) superfamily in B. bovis, as strong candidates for the development of subunit vaccines. Both RAP-1 and RRA share conservation of a group of 4 cysteines and amino acids motifs at the amino terminal end (NT) of these proteins. Methods and results: Sequence comparisons among the RRA sequences of several B. bovis strains and other Babesia spp parasites indicate a high level of conservation of a 15-amino acid (15-mer) motif located at the NT of the protein. BlastP searches indicate that the 15-mer motif is also present in adenylate cyclase, dynein, and other ATP binding proteins. AlphaFold2 structure predictions suggest partial exposure of the 15-mer on the surface of RRA of three distinct Babesia species. Antibodies in protected cattle recognize a synthetic peptide representing the 15-mer motif sequence in iELISA, and rabbit antibodies against the 15-mer react with the surface of free merozoites in immunofluorescence. Discussion and conclusion: The presence of the 15-mer-like regions in dynein and ATP-binding proteins provides a rationale for investigating possible functional roles for RRA. The demonstrated presence of a surface exposed B-cell epitope in the 15-mer motif of the B. bovis RRA, which is recognized by sera from protected bovines, supports its inclusion in future subunit epitope-based vaccines against B. bovis.


Assuntos
Antígenos de Protozoários , Babesia bovis , Babesiose , Proteínas de Protozoários , Animais , Bovinos , Motivos de Aminoácidos , Sequência de Aminoácidos , Anticorpos Antiprotozoários/imunologia , Antígenos de Protozoários/imunologia , Babesia bovis/imunologia , Babesiose/imunologia , Babesiose/parasitologia , Babesiose/prevenção & controle , Doenças dos Bovinos/imunologia , Doenças dos Bovinos/parasitologia , Doenças dos Bovinos/prevenção & controle , Sequência Conservada , Epitopos de Linfócito B/imunologia , Proteínas de Protozoários/imunologia , Vacinas Protozoárias/imunologia
14.
Prev Vet Med ; 228: 106213, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38744092

RESUMO

The common liver fluke, Fasciola hepatica, is a trematode parasite found worldwide, typically with a focal distribution due to its requirement for suitable climatic and environmental conditions to complete its lifecycle. Bovine fasciolosis causes suboptimal production and economic losses, including liver condemnation at slaughter. The lack of reliable diagnostic methods is a disadvantage to the increasing demand for surveillance and control. The aim of this study was to evaluate the diagnostic accuracy of bulk tank milk (BTM) antibody testing and aggregated abattoir registrations (AAR) of liver fluke as herd-level tests for F. hepatica infection using Bayesian latent class models. Data from the abattoirs in 2019-2021 and BTM, sampled in the winter of 2020/2021, were collected from 437 herds on the southwest coast of Norway. The BTM samples were analysed with the SVANOVIR® F. hepatica-Ab ELISA test, with results given as an optical density ratio (ODR), and later dichotomized using the recommended cut-off value from the test manufacturer (ODR ≥0.3). Based on the BTM ELISA test, 47.8% of the herds tested positive. The AAR test was defined as the herd-level proportion of female slaughtered animals registered with liver fluke infection during the study period. For this test, three cut-offs were used (a proportion of 0.05, 0.1 and 0.2). The herds were split into two subpopulations ("Coastal" and "Inland"), which were expected to differ in true prevalence of F. hepatica infection based on climate-related and geographical factors. The diagnostic accuracies of both tests were estimated using Bayesian latent class models with minimally informative priors. Post-hoc analysis revealed that the maximum sum of sensitivity (Se) and specificity (Sp) of the tests was achieved with a herd-level proportion of ≥0.1 registered with liver fluke as the AAR test. Using this cut-off, the median estimate for the diagnostic accuracy of the BTM ELISA was 90.4% (84.0-96.2 95% Posterior Credible Interval (PCI)) for Se and 95.3% (90.6-100% PCI) for Sp, while the median estimate of Se for AAR was 87.5% (81.4-93.1% PCI) and the median estimate of Sp for AAR was 91.0% (85.2-96.5% PCI). The cut-off evaluation of the SVANOVIR® F. hepatica-Ab ELISA test for BTM confirmed the manufacturer's recommended cut-off of ODR ≥0.3 to denote positive and negative herds. This study suggests that AAR and BTM ELISA test can be used as herd-level tools to monitor liver fluke infection, so that appropriate interventions against infection can be implemented as necessary.


Assuntos
Matadouros , Teorema de Bayes , Doenças dos Bovinos , Ensaio de Imunoadsorção Enzimática , Fasciola hepatica , Fasciolíase , Análise de Classes Latentes , Leite , Sensibilidade e Especificidade , Animais , Fasciolíase/veterinária , Fasciolíase/diagnóstico , Bovinos , Ensaio de Imunoadsorção Enzimática/veterinária , Ensaio de Imunoadsorção Enzimática/métodos , Fasciola hepatica/isolamento & purificação , Fasciola hepatica/imunologia , Doenças dos Bovinos/diagnóstico , Doenças dos Bovinos/parasitologia , Leite/parasitologia , Leite/química , Noruega/epidemiologia , Feminino , Prevalência , Anticorpos Anti-Helmínticos/análise
15.
Res Vet Sci ; 174: 105290, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38776695

RESUMO

This study reports assessment of the sensitivity of diagnostic techniques to detect T. vivax in experimentally infected cattle. Additionally, it describes T. vivax extravascular parasitism during the acute and chronic phases of trypanosomosis and congenital transmission. The T. vivax diagnosis was compared using blood samples collected from the jugular, coccygeal and ear tip veins. For this study, 13 males and two females were infected with ≈ 1 × 106 viable T. vivax trypomastigotes (D0). One animal was kept as a negative control during the entire study. The 13 infected males were euthanized between 14 and 749 days post-infection (DPI). After confirming the cyclicity of both females (9 months of age), they were naturally mated with a bull. One female was euthanized at 840 DPI, and the other at 924 DPI. The two calves, one from each female, were euthanized at six months of age (924 DPI), and the negative control at 924 DPI. During this period, T. vivax in blood was assessed using direct methods (Woo test, cPCR, microscopic examination of fresh wet blood films and parasite quantification - Brener method), and serological methods (IFAT, ELISA, and IA). Tissue samples were collected from the liver, spleen, brain, cerebellum, heart, testicles, epididymis, kidneys, eyeballs, pre-scapular lymph nodes, ear tips, mammary glands, uterus, and ovaries. The protozoan DNA was examined using LAMP. There was no difference in the detection of T. vivax using the Woo test and Brener method among the jugular, coccygeal, and ear tip veins. The sensitivity of the detection methods varied depending on the disease phase. Direct methods (Woo test, Brener method, and cPCR) demonstrated higher sensitivity during the acute phase, while serological methods (IFAT, ELISA, and IA) were more sensitive during the chronic phase. Anti-T. vivax antibodies were detected up to 924 DPI. Tissue evaluation using LAMP demonstrated the presence of T. vivax DNA and associated histopathological changes up to 840 or 924 DPI. Only in mammary glands and ovaries was no DNA detected. The most frequently observed histopathological alteration was lymphohistioplasmocytic inflammatory infiltrate. No transplacental transmission of T. vivax was observed.


Assuntos
Doenças dos Bovinos , Trypanosoma vivax , Animais , Bovinos , Feminino , Masculino , Doenças dos Bovinos/transmissão , Doenças dos Bovinos/parasitologia , Doenças dos Bovinos/sangue , Doenças dos Bovinos/diagnóstico , Transmissão Vertical de Doenças Infecciosas/veterinária , Tripanossomíase Africana/veterinária , Tripanossomíase Africana/transmissão , Tripanossomíase Africana/diagnóstico , Tripanossomíase Africana/sangue
16.
Ticks Tick Borne Dis ; 15(5): 102351, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38788485

RESUMO

The transplacental transmission of parasites and hemoparasites is crucial for understanding the epidemiology of diseases. This study aimed to assess the prevalence of hemopathogens in bovine fetuses at various gestational periods. Samples were obtained from a slaughterhouse in the state of Minas Gerais, Brazil, and a total of 236 fetuses were collected. DNA extracted from blood samples (145) and organ samples (a pool of brain and spleen) (236) underwent a nested PCR (nPCR) assay to detect Babesia spp., Theileria spp., Trypanosoma vivax, Anaplasma marginale, Anaplasma bovis, Anaplasma phagocytophilum, Ehrlichia minasensis, and hemotropic Mycoplasma spp. Additionally, serological analysis of 145 plasma samples was conducted using the indirect fluorescent antibody test-IFAT to detect IgG against Babesia bovis, Babesia bigemina, A. marginale, and Trypanosoma vivax. The observed prevalence of transplacental transmission was 19.3 %, 6.2 %, 42.7 % and 2.7 %, for A. marginale, B. bigemina, 'Candidatus M. haemobos', and Mycoplasma wenyonii, respectively. The prevalence of A. marginale by gestational trimester was 16 % (13/81) in the second trimester and 23 % (14/60) in the third trimester, with no positive samples in the first trimester. Regarding the species B. bovis and B. bigemina, all evaluated animals tested negative by nPCR, and no serological evidence for B. bovis was found by the IFAT. Babesia bigemina demonstrated an overall seroprevalence of 6.2 % (9/145), with 4.8 % (7/145) in the last trimester and 1.3 % (2/145) in the second trimester of pregnancy. In total, 42.7 % (62/145) of blood samples were positive for 'Candidatus M. haemobos', with 42 % (34/81) in the middle trimester, and 43 % (26/60) in the final trimester of pregnancy. Mycoplasma wenyonni was detected in 2.7 % (4/145) blood samples, all in coinfection with 'C. M. haemobos'. The prevalence by pregnancy trimester was 25 % (1/4) in the first trimester; 1.2 % (1/81) in the second trimester and 3.3 % (2/60) in the third trimester of pregnancy. Hemopathogen DNA was detected in fetus blood samples but not the brain or spleen samples. All the samples were negative for T. vivax, Theileria spp., Anaplasma spp. and Ehrlichia spp. Overall, in this study, approximately 70 % of fetuses were positive for one or more of the studied parasites. No significant associations were observed between pairs of pathogens, except 'C. M. haemobos' and A. marginale.


Assuntos
Doenças dos Bovinos , Mycoplasma , Animais , Brasil/epidemiologia , Bovinos , Feminino , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/microbiologia , Doenças dos Bovinos/parasitologia , Mycoplasma/isolamento & purificação , Gravidez , Prevalência , Babesia/isolamento & purificação , Feto/microbiologia , Feto/parasitologia , Infecções por Mycoplasma/epidemiologia , Infecções por Mycoplasma/veterinária , Infecções por Mycoplasma/microbiologia , Theileria/isolamento & purificação , Trypanosoma vivax/isolamento & purificação , Transmissão Vertical de Doenças Infecciosas/veterinária , Anaplasma/isolamento & purificação , Babesiose/epidemiologia , Babesiose/parasitologia , Anaplasmose/epidemiologia , Anaplasmose/microbiologia , Ehrlichia/isolamento & purificação
17.
Exp Appl Acarol ; 93(1): 71-79, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38811383

RESUMO

The aim of this work was to analyze the R. microplus (Canestrini, 1888) infestation in two bovine herds with different degrees of natural resistance (i.e., Hereford and Braford) to ticks subjected to an identical chemical treatment scheme to ticks at the same farm, to demonstrate the impact on tick control of the incorporation of a more resistant bovine breed. Two groups of ten Hereford and Braford cows each were subjected to eleven chemical treatments between August 2022 and October 2023 (four fluazuron, two fipronil 1%, one ivermectin 3.15% and four immersion in a dipping vat with a combination of cypermethrin 10% and ethion 40%). Tick population was shown to be susceptible to ivermectin, fluazuron and the mix cypermethrin 10%-ethion 40% and resistant to fipronil according to in vitro tests. Tick infestation was significantly greater in the Hereford cows than in the Braford cows. Tick infestation in both Hereford and Braford breeds was similar when treatment with functional drugs was applied, but when a block of the treatments was done with drugs with decreased functionality due to resistance (i.e. fipronil), treatment failure was manifested more strongly in the most susceptible breed. The incorporation of cattle breeds with moderate or high resistance to R. microplus is instrumental to optimize the efficacy and sustainability of chemical control of ticks in a scenario where resistance to one or more chemical groups is almost ubiquitous, because it favors the biological control of this parasite.


Assuntos
Acaricidas , Doenças dos Bovinos , Pirazóis , Rhipicephalus , Infestações por Carrapato , Animais , Bovinos , Rhipicephalus/fisiologia , Rhipicephalus/efeitos dos fármacos , Infestações por Carrapato/veterinária , Infestações por Carrapato/parasitologia , Acaricidas/farmacologia , Doenças dos Bovinos/parasitologia , Doenças dos Bovinos/tratamento farmacológico , Feminino , Pirazóis/farmacologia , Ivermectina/farmacologia , Compostos de Fenilureia/farmacologia , Controle de Ácaros e Carrapatos , Piretrinas/farmacologia
18.
Am J Trop Med Hyg ; 110(6): 1127-1136, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38697074

RESUMO

Animal African trypanosomiasis, also known as nagana, is caused by Trypanosoma species, which cause significant clinical diseases and lead to losses in animal production. We carried out a cross-sectional survey to investigate the composition of vectors and parasite diversity in two districts in the eastern region of Ghana where pigs and cattle were exposed to tsetse bites. We performed cytochrome c oxidase subunit 1 polymerase chain reaction (PCR) to identify tsetse species and internal transcribed spacer 1 PCR to identify Trypanosoma species. Also, we investigated the source of tsetse blood meal based on mitochondrial cytochrome b gene sequence analysis. A total of 229 tsetse, 65 pigs, and 20 cattle were investigated for trypanosomes. An overall vector density of 4.3 tsetse/trap/day was observed. A trypanosome prevalence of 58.9% (95% CI = 52.5-65.1%), 46.2% (95% CI = 34.6-58.1%), and 0.0% (95% CI = 0.0-16.1%) in tsetse, pigs, and cattle, respectively, was detected. Trypanosoma congolense was predominant, with a prevalence of 33.3% (95% CI = 73.3-86.5%) in tsetse. There was evidence of multiple infections in tsetse and pigs. Approximately 39% of the tsetse were positive for multiple infections of T. congolense and Trypanosoma simiae. Parasite prevalence in pigs across the communities was high, with significant differences associated between locations (χ2 = 28.06, 95% CI = 0.05-0.81, P = 0.0009). Tsetse blood meal analysis revealed feeding on domestic Sus scrofa domesticus (pigs) and Phacochoerus africanus (warthogs). Infective tsetse may transmit trypanosomes to livestock and humans in the communities studied.


Assuntos
Trypanosoma , Tripanossomíase Africana , Moscas Tsé-Tsé , Animais , Gana/epidemiologia , Moscas Tsé-Tsé/parasitologia , Bovinos , Tripanossomíase Africana/transmissão , Tripanossomíase Africana/epidemiologia , Tripanossomíase Africana/veterinária , Suínos , Trypanosoma/isolamento & purificação , Trypanosoma/genética , Trypanosoma/classificação , Estudos Transversais , Doenças dos Suínos/transmissão , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/parasitologia , Insetos Vetores/parasitologia , Florestas , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/transmissão , Doenças dos Bovinos/parasitologia , Prevalência , Feminino
20.
Vet Parasitol Reg Stud Reports ; 51: 101021, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38772638

RESUMO

Cystic echinococcosis (CE) causes significant losses in Andean livestock production and affects Andean food security. However, more studies are needed to understand the epidemiology of the disease. In addition, the potential contribution of Andean cattle to the transmission of Echinococcus granulosus sensu lato needs to be known. This study aimed to determine the CE-prevalence and its association with risk factors, such as age and sex of the animals, the parasite load (number of cysts/organ) of condemned organs, and the viability and fertility of Echinococcus cysts from cattle in the Andes. The prevalence was examined in 348 cattle from an authorized slaughterhouse of Huancayo at 3300 m altitude. Cyst burden was determined by extracting all cysts from the total of the CE-infected organs. Cyst fertility and protoscolices viability were analysed from 90 randomly selected CE-infected organs. The CE prevalence was 35.6% (124/348; 95% CI: 30.6%-40.6%). There was no significant effect of age and sex on CE prevalence. CE was significantly more prevalent (p < 0.05) in lungs than livers, 34.8% (121/348; 95% CI: 29.8%-39.8%) vs 8.9% (31/348; 95% CI: 5.9%-11.9%). Most (75%) infected organs had one to five cysts. The mean cyst burden was significantly (p = 0.018) higher in the lungs than livers, 6.4 ± 4.9 vs 3.7 ± 2.9. Cyst fertility was 1.6% (10/608; 95% CI: 0.6%-2.6%). Despite the high CE prevalence, infected organs from Andean cattle play a minor role in CE transmission to dogs in the central Peruvian Andes.


Assuntos
Doenças dos Bovinos , Equinococose , Echinococcus granulosus , Animais , Bovinos , Peru/epidemiologia , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/parasitologia , Doenças dos Bovinos/transmissão , Equinococose/epidemiologia , Equinococose/veterinária , Equinococose/transmissão , Masculino , Prevalência , Feminino , Echinococcus granulosus/isolamento & purificação , Fatores de Risco , Doenças Endêmicas/veterinária , Fígado/parasitologia , Pulmão/parasitologia
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