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1.
Exp Parasitol ; 218: 108012, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33011239

RESUMO

Chagas disease, caused by the protozoan Trypanosoma cruzi, is endemic in almost all countries of Latin America. In Brazil, oral infection is becoming the most important mechanism of transmission of the disease in several regions of the country. The gastrointestinal tract is the gateway for the parasite through this route of infection, however, little is known about the involvement of these organs related to oral route. In this sense, the present study evaluated the impact of oral infection on the digestive tract in mice infected by Berenice-78 (Be-78) T. cruzi strain, in comparison with the intraperitoneal route of infection. In this work, the intraperitoneal route group showed a peak of parasitemia similar to the oral route group, however the mortality rate among the orally infected animals was higher when compared to intraperitoneal route. By analyzing the frequency of blood cell populations, differences were mainly observed in CD4+ T lymphocytes, and not in CD8+, presenting an earlier reduction in the number of CD4+ T cells, which persisted for a longer period, in the animals of the oral group when compared with the intraperitoneal group. Animals infected by oral route presented a higher tissue parasitism and inflammatory infiltrate in stomach, duodenum and colon on the 28th day after infection. Therefore, these data suggest that oral infection has a different profile of parasitological and immune responses compared to intraperitoneal route, being the oral route more virulent and with greater tissue parasitism in organs of the gastrointestinal tract evaluated during the acute phase.


Assuntos
Doença de Chagas/patologia , Trato Gastrointestinal/patologia , Trato Gastrointestinal/parasitologia , Trypanosoma cruzi/patogenicidade , Administração Oral , Análise de Variância , Animais , Doença de Chagas/mortalidade , Doença de Chagas/parasitologia , Colo/parasitologia , Colo/patologia , Duodeno/parasitologia , Duodeno/patologia , Imunofenotipagem , Masculino , Camundongos , Monócitos/patologia , Parasitemia/mortalidade , Parasitemia/parasitologia , Estômago/parasitologia , Estômago/patologia , Taxa de Sobrevida
2.
Exp Parasitol ; 218: 108005, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32971132

RESUMO

Nematodiosis are responsible for financial losses in cattle production systems due to treatment costs, falling production rates and animal deaths. The incorporation of sodium alginate pellets containing nematophagous fungi in the bovine diet is a method for the control of nematodiosis. The aims of this study were to evaluate the viability of Arthrobotrys cladodes and Pochonia chlamydosporia contained in sodium alginate pellets after passage through the bovine gastrointestinal tract, as well as to evaluate the effects of single and combined use of these fungi against bovine parasitic nematodes. The reduction in parasitic nematode infective larvae of bovines by the combined use of Arthrobotrys cladodes and Pochonia chlamydosporia was more than the reduction in infective larvae by Arthrobotrys cladodes or Pochonia chlamydosporia alone in the collections 12, 24 and 36 h after giving the pellets to the animals. Arthrobotrys cladodes and Pochonia chlamydosporia combined promoted maximum reduction of infective larvae of 86.3%. Therefore, the combination of Arthrobotrys cladodes and Pochonia chlamydosporia may be an effective method to control gastrointestinal nematodiosis affecting grazing cattle.


Assuntos
Ascomicetos/fisiologia , Doenças dos Bovinos/prevenção & controle , Trato Gastrointestinal/microbiologia , Hypocreales/fisiologia , Infecções por Nematoides/veterinária , Análise de Variância , Animais , Ascomicetos/crescimento & desenvolvimento , Agentes de Controle Biológico , Bovinos , Doenças dos Bovinos/parasitologia , Fezes/parasitologia , Feminino , Trato Gastrointestinal/parasitologia , Hypocreales/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Micélio/crescimento & desenvolvimento , Nematoides/crescimento & desenvolvimento , Nematoides/microbiologia , Infecções por Nematoides/prevenção & controle
3.
Parasitol Res ; 119(9): 2813-2819, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32583163

RESUMO

Cryptosporidium is an opportunistic protozoan parasite that can inhabit in the gastrointestinal tract of various hosts. Cryptosporidium infection in black-boned goats and black-boned sheep may pose a threat to the survival and productivity, causing considerable economic losses to the livestock industry. However, it is yet to know whether black-boned goats and black-boned sheep in China are infected with Cryptosporidium. Thus, the objective of the present study was to investigate the prevalence and associated risk factors of Cryptosporidium infection in black-boned goats and black-boned sheep in Yunnan province, China. A total of 590 fecal samples were obtained from black-boned goats and black-boned sheep from five counties in Yunnan province, and the prevalence and species distribution of Cryptosporidium were determined by amplification of the 18S rDNA fragment using the nested PCR. The overall Cryptosporidium prevalence was 13.2% (78/590), with 18.0% (55/305) in black-boned goats and 8.1% (23/285) in black-boned sheep. The age and sampling site were identified as main factors that result in significant differences in Cryptosporidium prevalence. Three species, namely C. muris, C. xiaoi, and C. ubiquitum, were identified in black-boned goats and black-boned sheep in the present study, with C. muris (46/78) as the predominant species. This is the first report of Cryptosporidium infection in black-boned goats and black-boned sheep in China, and the findings will facilitate better understanding, prevention, and control of Cryptosporidium infection in black-boned goats and black-boned sheep in China.


Assuntos
Criptosporidiose/epidemiologia , Cryptosporidium/isolamento & purificação , Doenças das Cabras/parasitologia , Reação em Cadeia da Polimerase/veterinária , Doenças dos Ovinos/parasitologia , Animais , China/epidemiologia , Cryptosporidium/classificação , Cryptosporidium/genética , Fezes/parasitologia , Trato Gastrointestinal/parasitologia , Cabras/parasitologia , Prevalência , RNA Ribossômico 18S/genética , Fatores de Risco , Ovinos/parasitologia
4.
Exp Parasitol ; 216: 107936, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32535116

RESUMO

This study evaluated the germination capacity of Pochonia chlamydosporia (VC4) fungus after its passage through the gastrointestinal tract of domestic chickens and its interaction with Ascaridia galli and Heterakis gallinarum eggs. Twenty-two domestic chickens were divided in two groups: control group (G1) received shredded corn substrate without VC4; and treatment group (G2) received a single dose of 29 g corn substrate containing 3.3 × 106 conidia/chlamydospores (VC4). Subsequently, chicken fecal samples were collected at intervals of 0, 6, 8, 10, 12, 18 and 24 h. Petri dishes from fecal samples of the treated group (G2) were subdivided (G2a and G2b), and then replicated in 2% agar-water medium for the microbiological test. After VC4 growth, approximately 200 eggs of A. galli (G2a) and H. gallinarum (G2b) were added to each subgroup to evaluation of ovicidal activity. There was fungal viability after passage through chicken gastrointestinal tract and egg predation of 59.9% and 43.2% for A. galli and H. gallinarum, respectively. The present work demonstrates the ability of the fungus P. chlamydosporia to survive after passing through the gastrointestinal tract of domestic chickens, an extreme environment (low pH, enzymes, microbiota and mechanical action), and still germinate after being excreted with feces.


Assuntos
Ascaridíase/veterinária , Galinhas , Trato Gastrointestinal/microbiologia , Hypocreales/fisiologia , Doenças das Aves Domésticas/prevenção & controle , Infecções por Spirurida/veterinária , Animais , Ascaridia/microbiologia , Ascaridíase/prevenção & controle , Fezes/microbiologia , Feminino , Trato Gastrointestinal/parasitologia , Nematoides/fisiologia , Doenças das Aves Domésticas/parasitologia , Infecções por Spirurida/prevenção & controle , Spirurina/microbiologia
5.
Arq. bras. med. vet. zootec. (Online) ; 72(3): 1067-1068, May-June, 2020.
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1129778

RESUMO

A criação de equinos brasileira movimenta anualmente cerca de R$ 16,15 bilhões e impulsiona o setor econômico primário do país. O mercado de animais da raça Crioula vem se expandindo devido ao seu alto potencial zootécnico. No Rio Grande do Sul, a criação é tipicamente extensiva, aliada, muitas vezes, à alta densidade animal, o que favorece as constantes infecções por diversos parasitos. O objetivo deste estudo foi analisar retrospectivamente a frequência de parasitos gastrointestinais em cavalos da raça Crioula naturalmente infectados na região sul do Rio Grande do Sul. Foram utilizadas 585 amostras de fezes de equinos da raça Crioula, adultos, de ambos os sexos, recebidas de criatórios e centros reprodutivos localizados na região. Do total de amostras, 89,74% (525/585) foram positivas para algum helminto. Em 57,60% (337/585) das amostras, observaram-se somente ovos da família Strongylidae. Infecções por Parascaris spp. e Strongyloides sp., apresentaram frequências de 2,22% (13/585) e 1,53% (9/585), respectivamente. Assim, pode-se concluir que os parasitos mais frequentes na população equina da região sul do RS pertencem à família Strongylidae.(AU)


Assuntos
Animais , Infecções por Strongylida/epidemiologia , Estrongilídios , Trato Gastrointestinal/parasitologia , Cavalos/parasitologia , Brasil/epidemiologia , Helmintos
6.
PLoS One ; 15(5): e0226586, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32421720

RESUMO

It is vital to share details of concrete experiences of conducting a nationwide disease survey. By doing so, the global health community could adapt previous experiences to expand geographic mapping programs, eventually contributing to the development of disease control and elimination strategies. A nationwide survey of schistosomiasis and intestinal helminthiases was conducted from December 2016 to March 2017 in Sudan. We aimed to describe details of the key activities and cost components required for the nationwide survey. We investigated which activities were necessary to prepare and conduct a nationwide survey of schistosomiasis and intestinal helminthiases, and the types and amounts of transportation, personnel, survey equipment, and consumables that were required. In addition, we estimated financial and economic costs from the perspectives of the donor and the Ministry of Health. Cash expenditures incurred to implement the survey were defined as financial costs. For economic costs, we considered the true value for society as a whole, and this category therefore accounted for the costs of all goods and services used for the project, including those that were not sold in the market and therefore had no market price (e.g., time spent by head teachers and teachers). We organized costs into capital and recurrent items. We ran one-way sensitivity and probabilistic analyses using Monte-Carlo methods with 10,000 draws to examine the robustness of the primary analysis results. A total of USD 1,465,902 and USD 1,516,238 was incurred for the financial and economic costs, respectively. The key cost drivers of the nationwide survey were personnel and transportation, for both financial and economic costs. Personnel and transportation accounted for around 64% and 18% of financial costs, respectively. If a government finds a way to mobilize existing government officials with no additional payments using the health system already in place, the cost of a nationwide survey could be remarkably reduced.


Assuntos
Trato Gastrointestinal/patologia , Helmintíase/economia , Enteropatias Parasitárias/economia , Esquistossomose/economia , Feminino , Trato Gastrointestinal/parasitologia , Programas Governamentais , Helmintíase/epidemiologia , Helmintíase/parasitologia , Humanos , Enteropatias Parasitárias/epidemiologia , Enteropatias Parasitárias/parasitologia , Masculino , Esquistossomose/epidemiologia , Esquistossomose/parasitologia , Sudão/epidemiologia , Inquéritos e Questionários
7.
Appl Environ Microbiol ; 86(12)2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-32276975

RESUMO

Pollination provided by managed honey bees as well as by all the wild bee species is a crucial ecosystem service contributing to the conservation of biodiversity and human food security. Therefore, it is not only the health status of honey bees but also the health status of wild bees that concerns us all. In this context, recent field studies suggesting interspecies transmission of the microsporidium parasite Nosema ceranae from honey bees (Apis mellifera) to bumblebees (Bombus spp.) were alarming. On the basis of these studies, N. ceranae was identified as an emerging infectious agent (EIA) of bumblebees, although knowledge of its impact on its new host was still elusive. In order to investigate the infectivity, virulence, and pathogenesis of N. ceranae infections in bumblebees, we performed controlled laboratory exposure bioassays with Bombus terrestris by orally inoculating the bees with infectious N. ceranae spores. We comprehensively analyzed the infection status of the bees via microscopic analysis of squash preparations, PCR-based detection of N. ceranae DNA, histology of Giemsa-stained tissue sections, and species-specific fluorescence in situ hybridization. We did not find any evidence for a true infection of bumblebees by N. ceranae Through a series of experiments, we ruled out the possibility that spore infectivity, spore dosage, incubation time, or age and source of the bumblebees caused these negative results. Instead, our results clearly demonstrate that no infection and production of new spores took place in bumblebees after they ingested N. ceranae spores in our experiments. Thus, our results question the classification of N. ceranae as an emerging infectious agent for bumblebees.IMPORTANCE Emerging infectious diseases (EIDs) pose a major health threat to both humans and animals. EIDs include, for instance, those that have spread into hitherto naive populations. Recently, the honey bee-specific microsporidium Nosema ceranae has been detected by molecular methods in field samples of bumblebees. This detection of N. ceranae DNA in bumblebees led to the assumption that N. ceranae infections represent an EID of bumblebees and resulted in speculations on the role of this pathogen in driving bumblebee declines. In order to address the issue of whether N. ceranae is an emerging infectious agent for bumblebees, we experimentally analyzed host susceptibility and pathogen reproduction in this new host-pathogen interaction. Surprisingly, we did not find any evidence for a true infection of Bombus terrestris by N. ceranae, questioning the classification of N. ceranae infections as EIDs of bumblebees and demonstrating that detection of microsporidian DNA does not equal detection of microsporidian infection.


Assuntos
Abelhas/parasitologia , Interações Hospedeiro-Patógeno , Nosema/fisiologia , Animais , Trato Gastrointestinal/parasitologia , Especificidade da Espécie
8.
Virchows Arch ; 477(4): 593-595, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32170449

RESUMO

Microscopic foreign objects are sometimes found in gastrointestinal (GI) tract specimens. Some signify important diagnostic findings, such as parasitic or bacterial organisms and some medication resins. Partially digested fruits and vegetables can also be present, and some have been described in the literature as potential mimickers of clinically important findings. While animal protein appears as skeletal muscle on histologic examination, fruits and vegetables can show a wide variation under the microscope. To our knowledge, a thorough histologic examination of commonly eaten fruits and vegetables has not been published in the pathology literature. Herein, we present key morphologic features of fruits and vegetables that might be found in GI specimens, emphasizing potential mimics of significant pathologic findings.


Assuntos
Digestão , Ingestão de Alimentos , Frutas/citologia , Gastroenteropatias/patologia , Trato Gastrointestinal/patologia , Enteropatias Parasitárias/patologia , Preparações Farmacêuticas/análise , Verduras/citologia , Artefatos , Biópsia , Gastroenteropatias/parasitologia , Trato Gastrointestinal/química , Trato Gastrointestinal/parasitologia , Humanos , Enteropatias Parasitárias/parasitologia , Valor Preditivo dos Testes , Reprodutibilidade dos Testes
9.
BMC Evol Biol ; 20(1): 37, 2020 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-32171235

RESUMO

BACKGROUND: Various ecological groups of earthworms very likely constitute sharply isolated niches that might permit speciation of their symbiotic ciliates, even though no distinct morphological features appear to be recognizable among ciliates originating from different host groups. The nuclear highly variable ITS1-5.8S-ITS2 region and the hypervariable D1/D2 region of the 28S rRNA gene have proven to be useful tools for the delimitation of species boundaries in closely related free-living ciliate taxa. In the present study, the power of these molecular markers as well as of the secondary structure of the ITS2 molecule were tested for the first time in order to discriminate the species of endosymbiotic ciliates that were isolated from the gastrointestinal tract of three ecologically different groups of lumbricid earthworms. RESULTS: Nineteen new ITS1-5.8S-ITS2 region and D1/D2-28S rRNA gene sequences were obtained from five astome species (Anoplophrya lumbrici, A. vulgaris, Metaradiophrya lumbrici, M. varians, and Subanoplophrya nodulata comb. n.), which were living in the digestive tube of three ecological groups of earthworms. Phylogenetic analyses of the rRNA locus and secondary structure analyses of the ITS2 molecule robustly resolved their phylogenetic relationships and supported the distinctness of all five species, although previous multivariate morphometric analyses were not able to separate congeners in the genera Anoplophrya and Metaradiophrya. The occurrence of all five taxa, as delimited by molecular analyses, was perfectly correlated with the ecological groups of their host earthworms. CONCLUSIONS: The present study indicates that morphology-based taxonomy of astome ciliates needs to be tested in the light of molecular and ecological data as well. The use of morphological identification alone is likely to miss species that are well delimited based on molecular markers and ecological traits and can lead to the underestimation of diversity and overestimation of host range. An integrative approach along with distinctly increased taxon sampling would be helpful to assess the consistency of the eco-evolutionary trend in astome ciliates.


Assuntos
Cilióforos/classificação , Cilióforos/isolamento & purificação , DNA Espaçador Ribossômico/genética , Trato Gastrointestinal/parasitologia , Oligoquetos/parasitologia , RNA Ribossômico 28S/genética , Animais , Cilióforos/genética , DNA Espaçador Ribossômico/análise , Ecologia , Genes de RNAr/genética , Interações Hospedeiro-Parasita/fisiologia , Oligoquetos/classificação , Oligoquetos/genética , Filogenia , RNA Ribossômico , RNA Ribossômico 28S/análise , Análise de Sequência de DNA
10.
J Helminthol ; 94: e135, 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32127057

RESUMO

Haemonchus contortus is a haematophagous gastrointestinal nematode (GIN) that causes severe anaemia and even death in small ruminants, negatively impacting the economic viability of farms. Traditionally, this parasite has been controlled with chemical compounds; however, inadequate use of these types of products has favoured the emergence of anthelmintic resistance. Therefore, it is necessary to search for alternatives for GIN control. Previous studies have reported the anthelmintic activity of edible mushroom extracts against H. contortus. A recent study reported that a fraction constituted of different fatty acids and ß-sitosterol isolated from the basidiomata of the edible mushroom Pleurotus djamor ECS-123 has ovicidal and larvicidal activity against H. contortus. Thus, this study aimed to assess the anthelmintic activity of the pure molecules: pentadecanoic acid, palmitic acid, ß-sitosterol, stearic acid and linoleic acid. For this purpose, an egg-hatching inhibition test was carried out in which the compounds were evaluated individually and in combination at a final concentration of 20 mg mL-1. Furthermore, larval mortality was assessed using a combination of the five commercial compounds previously mentioned at different concentrations (1.25-20 mg mL-1). Palmitic acid and stearic acid, in some combinations, inhibited H. contortus egg hatching by 100%. On the other hand, in the larval mortality test, the combination of the five compounds showed dose-dependent behaviour, and 100% mortality was obtained 24 h post-incubation. Pure molecules and their combinations have anthelmintic-like activity against the eggs and larvae of H. contortus.


Assuntos
Antinematódeos/farmacologia , Ácidos Graxos/farmacologia , Haemonchus/efeitos dos fármacos , Sitosteroides/farmacologia , Agaricales/química , Animais , Bioensaio , Ácidos Graxos/química , Ácidos Graxos/classificação , Trato Gastrointestinal/parasitologia , Larva/efeitos dos fármacos , Masculino , Extratos Vegetais/farmacologia , Ovinos/parasitologia
11.
PLoS Negl Trop Dis ; 14(3): e0008014, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32126078

RESUMO

BACKGROUND: Leishmaniasis is a vector-borne neglected disease. Inside the natural sand fly vector, the promastigote forms of Leishmania undergo a series of extracellular developmental stages to reach the infectious stage, the metacyclic promastigote. There is limited information regarding the expression profile of L. infantum developmental stages inside the sand fly vector, and molecular markers that can distinguish the different parasite stages are lacking. METHODOLOGY/PRINCIPAL FINDINGS: We performed RNAseq on unaltered midguts of the sand fly Lutzomyia longipalpis after infection with L. infantum parasites. RNAseq was carried out at various time points throughout parasite development. Principal component analysis separated the transcripts corresponding to the different Leishmania promastigote stages, the procyclic, nectomonad, leptomonad and metacyclics. Importantly, there were a significant number of differentially expressed genes when comparing the sequential development of the various Leishmania stages in the sand fly. There were 836 differentially expressed (DE) genes between procyclic and long nectomonad promastigotes; 113 DE genes between nectomonad and leptomonad promastigotes; and 302 DE genes between leptomonad and metacyclic promastigotes. Most of the DE genes do not overlap across stages, highlighting the uniqueness of each Leishmania stage. Furthermore, the different stages of Leishmania parasites exhibited specific transcriptional enrichment across chromosomes. Using the transcriptional signatures exhibited by distinct Leishmania stages during their development in the sand fly midgut, we determined the genes predominantly enriched in each stage, identifying multiple potential stage-specific markers for L. infantum. CONCLUSIONS: Overall, these findings demonstrate the transcriptional plasticity of the Leishmania parasite inside the sand fly vector and provide a repertoire of potential stage-specific markers for further development as molecular tools for epidemiological studies.


Assuntos
Expressão Gênica , Marcadores Genéticos , Leishmania infantum/crescimento & desenvolvimento , Leishmania infantum/genética , Psychodidae/parasitologia , Animais , Feminino , Trato Gastrointestinal/parasitologia , Perfilação da Expressão Gênica , Análise de Sequência de RNA
12.
Vet Clin North Am Food Anim Pract ; 36(1): 1-15, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32029177

RESUMO

This article reviews the basics of gastrointestinal nematode biology and pathophysiology in cattle and describes how gastrointestinal nematode epidemiology is driven by environmental, host, and farm economic determinants. Adverse effects from gastrointestinal nematodes on their hosts are caused by tissue damage, nutrient absorption, immunopathologic effects, and reduced food intake induced by hormonal changes. Weather and microenvironmental factors influence the development and survival of free-living parasitic stages. A holistic control approach entails the consideration of environmental, immunologic, and socioeconomic aspects of nematode epidemiology and is key for the development and communication of sustainable control strategies.


Assuntos
Doenças dos Bovinos/parasitologia , Gastroenteropatias/veterinária , Infecções por Nematoides/veterinária , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Indústria de Laticínios/estatística & dados numéricos , Fezes/parasitologia , Feminino , Gastroenteropatias/parasitologia , Trato Gastrointestinal/parasitologia , Nematoides/isolamento & purificação , Infecções por Nematoides/epidemiologia
13.
Vet Clin North Am Food Anim Pract ; 36(1): 59-71, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32029189

RESUMO

Parasite species infecting cattle throughout northern North American are generally the same as those found throughout North America. Throughout Canada, cattle are primarily infected with Ostertagia ostertagi and Cooperia oncophora, whose larvae survive cold winters within soil of pastures. Overwintering larvae of these species maintain a temporary population of refugia available in spring to grazing cattle. Cattle from northern United States are also infected with Cooperia punctata and Haemonchus placei, whose larvae cannot survive cold winters within pastures. Anthelmintics with persistent activity are used during spring to recover some of these losses; however, anthelmintic resistance limits effectiveness of this strategy.


Assuntos
Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/prevenção & controle , Infecções por Nematoides/veterinária , Animais , Anti-Helmínticos/administração & dosagem , Bovinos , Doenças dos Bovinos/tratamento farmacológico , Doenças dos Bovinos/parasitologia , Indústria de Laticínios/métodos , Feminino , Trato Gastrointestinal/parasitologia , Nematoides/isolamento & purificação , Infecções por Nematoides/tratamento farmacológico , Infecções por Nematoides/epidemiologia , Infecções por Nematoides/prevenção & controle , América do Norte/epidemiologia , Estações do Ano
14.
Vet Clin North Am Food Anim Pract ; 36(1): 45-57, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32029188

RESUMO

Control of gastrointestinal nematodes (GIN) can have both economic and health benefits for cattle operations in the southern United States. In the past several decades, GIN control has relied almost exclusively on the use of anthelmintics. With the increase in anthelmintic resistance new strategies must be developed. Anthelmintic use should be minimized by integrating grazing management and a good herd health program into GIN control programs. This takes knowledge of GIN biology and epidemiology in the region (climate and weather) combined with specific information from the ranch.


Assuntos
Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/prevenção & controle , Gastroenteropatias/veterinária , Infecções por Nematoides/veterinária , Animais , Anti-Helmínticos/administração & dosagem , Canadá/epidemiologia , Bovinos , Doenças dos Bovinos/parasitologia , Clima , Fezes/parasitologia , Gastroenteropatias/epidemiologia , Gastroenteropatias/parasitologia , Gastroenteropatias/prevenção & controle , Trato Gastrointestinal/parasitologia , Nematoides/isolamento & purificação , Infecções por Nematoides/epidemiologia , Infecções por Nematoides/parasitologia , Infecções por Nematoides/prevenção & controle , Estados Unidos/epidemiologia
15.
Vet Clin North Am Food Anim Pract ; 36(1): 73-87, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32029190

RESUMO

Strongylid gastrointestinal nematodes are an important cause of disease and economic loss in small ruminants. These parasites are important in most of the United States, with the bloodsucking parasite Haemonchus contortus being the predominant species of concern. Sheep and goats are infected while grazing, and the biology of infective larvae on pastures is important in the design of parasite management programs. Widespread resistance to anthelmintics requires strategies designed to preserve remaining drug activity; these include combination treatments with multiple classes of anthelmintics and targeted treatments.


Assuntos
Doenças das Cabras/epidemiologia , Doenças das Cabras/prevenção & controle , Infecções por Nematoides/veterinária , Doenças dos Ovinos/epidemiologia , Doenças dos Ovinos/prevenção & controle , Animais , Anti-Helmínticos/administração & dosagem , Trato Gastrointestinal/parasitologia , Doenças das Cabras/tratamento farmacológico , Doenças das Cabras/parasitologia , Cabras , Nematoides/isolamento & purificação , Infecções por Nematoides/tratamento farmacológico , Infecções por Nematoides/epidemiologia , Infecções por Nematoides/prevenção & controle , Ovinos , Doenças dos Ovinos/tratamento farmacológico , Doenças dos Ovinos/parasitologia
16.
Rev Bras Parasitol Vet ; 29(1): e013119, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32049139

RESUMO

The objective of this study was to evaluate the efficacy of carvacryl acetate (CVA) and nanoencapsulated CVA (nCVA) on gastrointestinal nematodes of sheep. The CVA was nanoencapsulated with chitosan/gum arabic and the efficacy of nanoencapsulation (EE), yield, zeta potential, nanoparticle morphology and release kinetics at pH 3 and 8 were analyzed. Acute and subchronic toxicity were evaluated in rodents and reduction of egg counts in the faeces (FECRT) of sheep. The sheep were divided into four groups (n = 10): G1, 250 mg/kg CVA; G2, 250 mg/kg nCVA; G3, polymer matrix and G4: 2.5 mg/kg monepantel. EE and nCVA yield were 65% and 57%, respectively. The morphology of the nanoparticles was spherical, size (810.6±286.7 nm), zeta potential in pH 3.2 (+18.3 mV) and the 50% release of CVA at pHs 3 and 8 occurred at 200 and 10 h, respectively. nCVA showed LD50 of 2,609 mg/kg. CVA, nCVA and monepantel reduced the number of eggs per gram of faeces (epg) by 57.7%, 51.1% and 97.7%, respectively. The epg of sheep treated with CVA and nCVA did not differ from the negative control (P>0.05). Nanoencapsulation reduced the toxicity of CVA; however, nCVA and CVA presented similar results in the FECRT.


Assuntos
Anti-Helmínticos/administração & dosagem , Trato Gastrointestinal/parasitologia , Monoterpenos/administração & dosagem , Nanocápsulas/administração & dosagem , Nematoides/efeitos dos fármacos , Infecções por Nematoides/tratamento farmacológico , Doenças dos Ovinos/tratamento farmacológico , Animais , Anti-Helmínticos/toxicidade , Fezes/parasitologia , Feminino , Camundongos , Monoterpenos/toxicidade , Nanocápsulas/toxicidade , Nematoides/classificação , Nematoides/isolamento & purificação , Infecções por Nematoides/parasitologia , Contagem de Ovos de Parasitas , Testes de Sensibilidade Parasitária , Reação em Cadeia da Polimerase em Tempo Real , Roedores , Ovinos , Doenças dos Ovinos/parasitologia , Testes de Toxicidade
17.
J Helminthol ; 94: e125, 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-32036795

RESUMO

Our objective was to measure the efficacy of ivermectin (IVM) and benzimidazoles (BZ, i.e. fenbendazole and albendazole) in 15 cattle farms in western France and southern Italy. A total of 11 groups were treated with IVM and 11 with BZ. Efficacy was assessed by calculating the percentage of faecal egg count reduction (%FECR) using the pre- and post-treatment arithmetic means. Anthelmintic resistance was considered to be present when the %FECR was <95% and the lower limit of the 95% confidence interval <90%. For IVM, the percentages of FECR ranged from 73% to 100%. Lack of efficacy to IVM was detected in two farms out of four in France, but was not detected in any of the seven farms in Italy. For BZ, the percentages of FECR ranged from 95% to 100%. No case of BZ resistance was detected in the five farms in France and the six farms in Italy.


Assuntos
Anti-Helmínticos/uso terapêutico , Doenças dos Bovinos/tratamento farmacológico , Gastroenteropatias/veterinária , Nematoides/efeitos dos fármacos , Infecções por Nematoides/veterinária , Animais , Benzimidazóis/uso terapêutico , Bovinos , Doenças dos Bovinos/parasitologia , Fazendas , Fezes/parasitologia , França , Gastroenteropatias/tratamento farmacológico , Gastroenteropatias/parasitologia , Trato Gastrointestinal/parasitologia , Itália , Ivermectina/uso terapêutico , Infecções por Nematoides/tratamento farmacológico , Contagem de Ovos de Parasitas
18.
Acta Vet Scand ; 62(1): 9, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-32024529

RESUMO

The study aimed to compare the gastrointestinal helminthofauna of free-ranging wild boars from arable lands and forests, which are the natural habitats for wild boar in Poland and further to investigate if wild boars living in agricultural environments could acquire helminths commonly detected in domestic pigs. In 2011-2014, a total of 57 wild boars were examined post-mortem for the presence of gastrointestinal nematodes. Altogether, all but two of the animals were infected, and seven nematode species were found. The mean infection burden was 68.9 parasites, ranging from 1 to 381 worms. In forest areas, Ascarops strongylina, Physocephalus sexalatus, and Globocephalus urosubulatus were common, whereas on arable lands, the animals were more frequently infected (P < 0.05) by Ascaris suum and Trichuris suis, which are parasites that commonly occur in domestic pigs. Oesophagostomum dentatum was observed only in wild boars on arable lands, and Bourgelatia diducta, which is alien to European suids, appeared irrespective of habitat type. These results show significant differences in parasite spectra among wild boars living in forests or arable lands in Poland and indicates the risks of parasite transfer from domestic pigs to free-ranging wild boars. Furthermore, in farmed game, organic farming, or in the case of agritourism farms, one should be aware of the risk of related animals acquiring new and alien parasite infections by being kept outdoors.


Assuntos
Trato Gastrointestinal/parasitologia , Infecções por Nematoides/veterinária , Sus scrofa/parasitologia , Doenças dos Suínos/parasitologia , Agricultura , Animais , Biodiversidade , Florestas , Nematoides/classificação , Nematoides/isolamento & purificação , Infecções por Nematoides/parasitologia , Contagem de Ovos de Parasitas/veterinária , Polônia , Suínos
19.
Zoolog Sci ; 37(1): 31-41, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32068372

RESUMO

Immune defense is costly to maintain and deploy, and the optimal investment into immune defense depends on risk of infection. Altitude is a natural environmental factor that is predicted to affect parasite abundance, with lower parasite abundance predicted at higher altitudes due to stronger environmental stressors, which reduce parasite transmission. Using high and low altitude populations of the Turkish blind mole-rat (TBMR) Nannospalax xanthodon, we tested for effects of altitude on constitutive innate immune defense. Field studies were performed with 32 wild animals in 2017 and 2018 from two low- and one high-altitude localities in the Central Taurus Mountains, at respective altitudes of 1010 m, 1115 m, and 2900 m above sea level. We first compared innate standing immune defense as measured by the bacteria-killing ability of blood serum. We then measured corticosterone stress hormone levels, as stressful conditions may affect immune response. Finally, we compared prevalence and intensity of gastrointestinal parasites of field-captured TBMR. We found that the bacteria-killing ability of serum is greater in the mole-rat samples from high altitude. There was no significant difference in stress (corticosterone) levels between altitude categories. Coccidian prevalence and abundance were significantly higher in 2017 than 2018 samples, but there was no significant difference in prevalence, abundance, or intensity between altitudes, or between sexes. Small sample sizes may have reduced power to detect true differences; nevertheless, this study provides support that greater standing innate immunity in high altitude animals may reflect greater investment into constitutive defense.


Assuntos
Altitude , Imunidade Inata , Ratos-Toupeira/imunologia , Animais , Coccídios/isolamento & purificação , Corticosterona/sangue , Feminino , Trato Gastrointestinal/parasitologia , Masculino , Nematoides/isolamento & purificação , Contagem de Ovos de Parasitas/métodos , Contagem de Ovos de Parasitas/veterinária , Teste Bactericida do Soro/métodos , Teste Bactericida do Soro/veterinária
20.
Int J Parasitol ; 50(2): 161-169, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32004511

RESUMO

Marshallagia marshalli is a multi-host gastrointestinal nematode that infects a variety of artiodactyl species from temperate to Arctic latitudes. Eggs of Marshallagia are passed in host faeces and develop through three larval stages (L1, L2, and L3) in the environment. Although eggs normally hatch as L1s, they can also hatch as L3s. We hypothesised that this phenotypic plasticity in hatching behaviour may improve fitness in subzero and highly variable environments, and this may constitute an evolutionary advantage under current climate change scenarios. To test this, we first determined if the freeze tolerance of different free-living stages varied at different temperatures (-9 °C, -20 °C and -35 °C). We then investigated if there were differences in freeze tolerance of M. marshalli eggs sourced from three discrete, semi-isolated, populations of wild bighorn and thinhorn sheep living in western North America (latitudes: 40°N, 50°N, 64°N). The survival rates of eggs and L3s were significantly higher than L1s at -9 °C and -20 °C, and survival of all three stages decreased significantly with increasing freeze duration and decreasing temperature. The survival of unhatched L1s was significantly higher than the survival of hatched L1s. There was no evidence of local thermal adaptation in freeze tolerance among eggs from different locations. We conclude that developing to the L3 in the egg may result in a fitness advantage for M. marshalli, with the egg protecting the more vulnerable L1 under freezing conditions. This phenotypic plasticity in life-history traits of M. marshalli might be an important capacity, a potential exaptation capable of enhancing parasite fitness under temperature extremes.


Assuntos
Carneiro da Montanha/parasitologia , Ovinos/parasitologia , Infecções por Strongylida/veterinária , Trichostrongyloidea/fisiologia , Aclimatação , Adaptação Fisiológica , Animais , Mudança Climática , Ovos , Fezes/parasitologia , Congelamento , Trato Gastrointestinal/parasitologia , Nematoides/parasitologia , Nematoides/fisiologia , América do Norte , Dinâmica Populacional , Ruminantes , Doenças dos Ovinos/parasitologia , Temperatura , Trichostrongyloidea/parasitologia
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