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1.
Sci Rep ; 13(1): 8965, 2023 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-37268693

RESUMO

Fungal strains used in the biocontrol of animal gastrointestinal parasites have been mainly isolated from pasture soil, decaying organic matter, and feces from herbivores and carnivores. However, their isolation from birds and assessment of predatory activity against avian GI parasites has been scarce thus far. This research aimed to isolate filamentous fungi from avian fecal samples and evaluate their predatory activity against coccidia. A pool of 58 fecal samples from chickens, laying hens, and peacocks, previously collected between July 2020-April 2021, were used for isolation of filamentous fungi and assessment of their in vitro predatory activity against coccidian oocysts, using Water-Agar medium and coprocultures. The Willis-flotation technique was also performed to obtain concentrated suspensions of oocysts. A total of seven Mucor isolates was obtained, being the only fungal taxa identified, and all presented lytic activity against coccidia. Isolates FR3, QP2 and SJ1 had significant coccidiostatic efficacies (inhibition of sporulation) higher than 70%, while isolates FR1, QP2 and QP1 had coccidicidal efficacies (destruction of the oocysts) of 22%, 14% and 8%, respectively, after 14 days of incubation, being a gradual and time-dependent process. To our knowledge, this is the first report regarding the isolation of native predatory fungi from avian feces and demonstration of their lytic activity against coccidia.


Assuntos
Galinhas , Coccídios , Animais , Feminino , Oocistos , Fezes/parasitologia , Fungos
2.
BMC Vet Res ; 17(1): 102, 2021 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-33663511

RESUMO

BACKGROUND: In free-ranging reptile populations, bacterial, fungal, viral and parasitic pathogens may affect hosts through impairment in movements, thermoregulation, reproduction, survival, and population dynamics. The speckled dwarf tortoise (Chersobius [Homopus] signatus) is a threatened species that is mostly restricted to the Succulent Karoo biome in South Africa, and little information on pathogens of this species is available yet. We derived baseline parameters for five males and five females that were captured to genetically enhance a conservation breeding program in Europe. Upon collection of the tortoises, ticks were removed and identified. Immediately upon arrival in Europe, ocular, nasal, oral and cloacal swabs were taken for viral, bacteriological and mycological examinations. Fecal samples were collected before and 1 month after fenbendazole treatment, and analyzed for parasites. A panel of PCR, aiming to detect herpesviruses, adenoviruses and iridoviruses, was carried out. RESULTS: Samples were negative for viruses, while bacteriological examination yielded detectable growth in 82.5% of the swabs with a mean load of 16 × 107 ± 61 × 108 colony forming units (CFU) per swab, representing 34 bacterial species. Cloacal and oral swabs yielded higher detectable growth loads than nasal and ocular swabs, but no differences between sexes were observed. Fungi and yeasts (mean load 5 × 103 ± 13 × 103 CFU/swab) were detected in 25% of the swabs. All pre-treatment fecal samples were positive for oxyurid eggs, ranging from 200 to 2400 eggs per gram of feces, whereas after the treatment a significantly reduced egg count (90-100% reduction) was found in seven out of 10 individuals. One remaining individual showed 29% reduction, and two others had increased egg counts. In five tortoises, Nycthocterus spp. and coccidian oocysts were also identified. Soft ticks were identified as Ornithodoros savignyi. CONCLUSIONS: Our baseline data from clinically healthy individuals will help future studies to interpret prevalences of microorganisms in speckled dwarf tortoise populations. The study population did not appear immediately threatened by current parasite presence.


Assuntos
Infestações por Carrapato/veterinária , Tartarugas/microbiologia , Tartarugas/parasitologia , Animais , Antinematódeos/uso terapêutico , Bactérias/classificação , Cilióforos/isolamento & purificação , Coccídios/isolamento & purificação , Feminino , Fenbendazol/uso terapêutico , Fungos/classificação , Masculino , Ornithodoros , Infecções por Oxyurida/tratamento farmacológico , África do Sul/epidemiologia
3.
Zoology (Jena) ; 136: 125709, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31539860

RESUMO

Sexual organisms should be better suited than asexual ones in a context of continuous evolution in response to opposite organisms in changing environments ("Red Queen" hypothesis of sex). However, sex also carries costs associated with the maintenance of males and mating (sex cost hypothesis). Here, both non-mutually excluding hypotheses are tested by analysing the infestation by haemogregarines of mixed communities of Darevskia rock lizards composed of parthenogens generated by hybridisation and their bisexual relatives. Prevalence and intensity were recorded from 339 adult lizards belonging to six species from five syntopic localities and analysed using Generalized Mixed-Models (GLMM). Both infestation parameters depended on host-size (like due to longer exposure with age), sex and, for intensity, species. Once accounting for locality and species, males were more parasitized than conspecific females with bisexual species, but no signal of reproductive mode itself on parasitization was recovered. Essentially, male-male interactions increased haemogregarine intensity while females either sexual or asexual had similar reproductive costs when in the same conditions. These findings deviate from the predictions from "Red Queen" dynamics while asymmetric gender costs are here confirmed. Thus, increased parasitization pressure on males adds to other costs, such as higher social interactions and lower fecundity, to explain why parthenogenetic lizards apparently prevail in the short-term evolutionary scale. How this is translated in the long-term requires further phylogenetic analysis.


Assuntos
Sangue/parasitologia , Coccídios/fisiologia , Lagartos/parasitologia , Doenças Parasitárias em Animais/fisiopatologia , Partenogênese/fisiologia , Animais , Feminino , Masculino , Doenças Parasitárias em Animais/parasitologia , Reprodução
4.
Res Vet Sci ; 97(1): 1-7, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24975324

RESUMO

Caprine besnoitiosis, caused by the cyst-forming protozoal apicomplexan Besnoitia caprae appears to be endemic in Kenya, Nigeria and Iran, but has yet to be detected in other parts of the world. The infection causes an important parasitic disease of goats in affected developing countries. Bovine besnoitiosis, is a widespread disease of cattle in Africa, Asia (but not Iran) and southern Europe. Recent epidemiological data confirm that the incidence and geographical range of bovine besnoitiosis in Europe is increasing, which is why growing attention has been given to the condition during the past decade. This paper reviews pertinent information on the biology, epidemiology, pathology, clinical signs, diagnosis and control of caprine besnoitiosis, together with its similarities to, and differences from, bovine besnoitiosis. The serious economic consequences of besnoitiosis on goat breeding and local meat and hide industries is also considered.


Assuntos
Doenças dos Bovinos/epidemiologia , Coccídios/patogenicidade , Coccidiose/veterinária , Doenças das Cabras/epidemiologia , Cabras/parasitologia , Sarcocystidae/patogenicidade , Animais , Ásia/epidemiologia , Cruzamento/economia , Bovinos , Doenças dos Bovinos/economia , Coccidiose/economia , Coccidiose/epidemiologia , Europa (Continente)/epidemiologia , Doenças das Cabras/economia , Incidência , Irã (Geográfico)/epidemiologia , Quênia/epidemiologia , Produtos da Carne/economia , Produtos da Carne/parasitologia , Nigéria/epidemiologia
5.
J Parasitol ; 99(5): 883-7, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23537006

RESUMO

The Apicomplexa are intracellular pathogens of animals, with the Coccidia being the largest group. Among these are the hemogregarines, which include some of the most common hemoparasites found in reptiles. Several studies have reported a possible pattern of prey-predator transmission for some of these parasites. Snakes from the Mediterranean region have been found to be parasitized with Hepatozoon spp. similar to those in lacertids and gekkonids, supporting the prey-predator transmission hypothesis. Here we analyzed specimens of the saurophagous genus Psammophis from North Africa, an ecologically different region. Through molecular analysis of tissue samples we detected 3 different apicomplexan parasites: Caryospora, Sarcocystis, and Hepatozoon. Caryospora was detected in a Forskål's sand snake Psammophis schokari from Algeria, constituting the first time these parasites have been detected from a tissue sample through molecular screening. The obtained Sarcocystis phylogeny does not reflect the relationships of their final hosts, with the parasites identified from snakes forming at least 3 unrelated groups, indicating that it is still premature to predict definitive host based on the phylogeny of these parasites. Three unrelated lineages of Hepatozoon parasites were identified in Psammophis, each closely related to lineages previously identified from different lizard groups, on which these snakes feed. This once again indicates that diet might be a key element in transmission, at least for Hepatozoon species of saurophagous snakes.


Assuntos
Coccídios/classificação , Coccidiose/veterinária , Dieta/veterinária , Serpentes/parasitologia , Animais , Teorema de Bayes , Coccídios/genética , Coccidiose/parasitologia , DNA de Protozoário/química , DNA de Protozoário/isolamento & purificação , Interações Hospedeiro-Parasita , Funções Verossimilhança , Lagartos/parasitologia , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 18S/genética , RNA Ribossômico 28S/genética , Sarcocystis/classificação , Sarcocystis/genética , Sarcocistose/parasitologia , Sarcocistose/veterinária
6.
Trans R Soc Trop Med Hyg ; 102(6): 520-1, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18405928

RESUMO

In many resource-poor countries, diagnosis of tuberculosis is based on microscopy of Ziehl-Neelsen-stained smears. However, the fluorescent stain auramine performs better and allows the detection of more positive smears. The limitation for its widespread use has been the high cost for fluorescent microscopes, especially the frequent replacement of the expensive light source, which lasts only 200-300 h. Novel light-emitting diodes (LED) are alternatives and last ten thousands of hours. Based on LEDs, rather inexpensive solutions for fluorescent microscopes are now available and thus auramine may be a cost-effective step to improve the diagnosis of tuberculosis in resource-poor countries.


Assuntos
Benzofenoneídio , Coccidiose/diagnóstico , Corantes , Microscopia de Fluorescência/métodos , Mycobacterium tuberculosis/isolamento & purificação , Tuberculose Pulmonar/diagnóstico , Animais , Coccídios/isolamento & purificação , Custos e Análise de Custo , Desenho de Equipamento , Humanos , Microscopia de Fluorescência/normas , Coloração e Rotulagem/métodos
7.
Bull Math Biol ; 66(5): 1285-311, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15294426

RESUMO

We have developed a classification function that is capable of discriminating between anticoccidial and nonanticoccidial compounds with different structural patterns. For this purpose, we calculated the Markovian electron delocalization negentropies of several compounds. These molecular descriptors, which act as molecular fingerprints, are derived from an electronegativity-weighted stochastic matrix (1Pi). The method attempts to describe the delocalization of electrons with time during the process of molecule formation by considering the 3D environment of the atoms. Accordingly, the entropies of this random process are used as molecular descriptors. The present study involves a stochastic generalization of the original idea described by Kier, which concerned the use of molecular negentropies in QSAR. Linear discriminant analysis allowed us to fit the discriminant function. This function has given rise to a good classification of 82.35% (28 anticoccidials out of 34) and 91.8% of inactive compounds (56/61) in training series. An overall classification of 88.42% (84/95) was achieved. Validation of the model was carried out by means of an external predicting series and this gave a global predictability of 93.1%. Finally, we report the experimental assay (more than 95% of lesion control) of two compounds selected from a large data set through virtual screening. We conclude that the approach described here seems to be a promising 3D-QSAR tool based on the mathematical theory of stochastic processes.


Assuntos
Coccídios/crescimento & desenvolvimento , Coccidiose/tratamento farmacológico , Coccidiostáticos/farmacologia , Modelos Biológicos , Animais , Coccidiostáticos/química , Desenho de Fármacos , Humanos , Cadeias de Markov , Relação Quantitativa Estrutura-Atividade , Processos Estocásticos
8.
Parasitol Res ; 87(11): 973-5, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11728025

RESUMO

Progress in the treatment and prophylaxis of cyst-forming coccidial infections (Neospora, Sarcocystis Toxoplasma) and Cryptosporidium infections has been limited (Table 1: Haberkorn 1996: Croft 1997: Wang 1997). However, new possibilities have been opened up in the treatment of Eimeria-induced coccidiosis in poultry and mammals. due to improvements in treatment and, or metaphylaxis. A new polyether antibiotic. semduramycin, has recently been added to the range of effective prophylactic preparations. The development of resistance to anticoccidial agents is now posing similar problems to those encountered with malaria, coccidiosis in poultry being particularly affected. Because no new active ingredient from a new family of chemical substances has been developed for more than 10 years, the following approaches are being adopted to get round this problem: the use of older preparations which have not been used for a long time, the introduction of combinations such as narasin nicarbazin or methyl benzoquate clopidol and the alternating use of anticoccidial agents in rotation and shuttle programmes. The goal of a real alternative, i.e. vaccination, has been achieved to a certain extent in the form of live vaccines for laying hens and broiler breeders and is being practiced in some countries.


Assuntos
Antiprotozoários/uso terapêutico , Coccídios/efeitos dos fármacos , Coccidiose/veterinária , Desenho de Fármacos , Indústria Farmacêutica/tendências , Animais , Antiprotozoários/classificação , Coccídios/genética , Coccídios/metabolismo , Coccidiose/tratamento farmacológico , Coccidiose/prevenção & controle
9.
Parasitol. día ; 20(3/4): 118-24, jul.-dic. 1996. tab
Artigo em Espanhol | LILACS | ID: lil-202471

RESUMO

Orientado hacia la promoción de nuevos productos de actividad anticoccidial, entre otras acciones se evaluó la eficacia de dos productos, Salstop y Digestor Broilers (Citrade CA) para el control de la coccidiosis aviar, en un ensayo en piso con pollos de engorde. Se utilizaron 240 pollitos de 1 día de edad, distribuidos al azar en 6 grupos experimentales, con 4 réplicas c/u de 10 pollitos-réplica: I= Salstop-Inoculado; II= Salstop-No inoculado; III= Digestor Broilers-Inoculado; IV= Digestor Broilers-No Inoculado; V= No medicado-Inoculado (control+) y VI= No Medicado-No Inoculado (control-). Las aves se medicaron vía alimento desde el 1 día de edad, a la dosis de: Salstop 50 g/ton (grupos I y II) y Digestor Broilers 1 kg/ton (grupos III y IV), realizándose el reto parasitario al día 15 de edad de las aves, de manera individual (grupos I, III y V). Se registró datos y cálculos de pesos semanales, ganancias de peso, consumo de alimento, conversión alimenticia, producción e índice de oocystos, score e índice de lesiones, mortalidad, cuadro clínico, índice anticoccidial e índice de productividad Salstop y Digestor Broilers, resultaron con una eficacia moderada contra la coccidiosis aviar al evaluar los índices anticoccidiales y de productividad. Por evidenciarse lesiones severas en el ciego se deduce una nula actividad contra la E. tenella; ambas tuvieron un efecto como promotores del crecimiento


Assuntos
Animais , Bebidas , Citrus , Coccidiose/tratamento farmacológico , Coccidiostáticos/uso terapêutico , Galinhas/parasitologia , Coccídios/efeitos dos fármacos , Coccidiose , Eimeria tenella/efeitos dos fármacos , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
10.
J Clin Pathol ; 45(11): 968-74, 1992 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1452791

RESUMO

AIMS: To assess the results from parasitology laboratories taking part in a quality assessment scheme between 1986 and 1991; and to compare performance with repeat specimens. METHODS: Quality assessment of blood parasitology, including tissue parasites (n = 444; 358 UK, 86 overseas), and faecal parasitology, including extra-intestinal parasites (n = 205; 141 UK, 64 overseas), was performed. RESULTS: Overall, the standard of performance was poor. A questionnaire distributed to participants showed that a wide range of methods was used, some of which were considered inadequate to achieve reliable results. Teaching material was distributed to participants from time to time in an attempt to improve standards. CONCLUSIONS: Since the closure of the IMLS fellowship course in 1972, fewer opportunities for specialised training in parasitology are available: more training is needed. Poor performance in the detection of malarial parasites is mainly attributable to incorrect speciation, misidentification, and lack of equipment such as an eyepiece graticule.


Assuntos
Parasitologia/normas , Patologia Clínica/normas , Animais , Sangue/parasitologia , Cestoides/isolamento & purificação , Coccídios/isolamento & purificação , Eucariotos/isolamento & purificação , Fezes/parasitologia , Humanos , Nematoides/isolamento & purificação , Parasitologia/educação , Controle de Qualidade , Trematódeos/isolamento & purificação , Reino Unido
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