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1.
Microb Pathog ; 139: 103916, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31812772

RESUMO

The objective of this study was to determine whether curcumin and a commercial microencapsulated phytogenic supplement containing thymol, cinnamaldehyde and carvacrol in broiler chicken feed would improve health and meat quality (fatty acid profile), as well as to determine the coccidiostatic and bactericidal potential of the additives. The broiler chickens were divided into five groups: NC - negative control feed; PC - positive control; CU - with 50 mg/kg of curcumin, PHY - 100 mg/kg phytogenic; and PHY + CU, a combination of both additives at 50 mg/kg (curcumin) and 100 mg/kg (phytogenic). We observed significantly higher levels of total proteins associated with increased circulating globulins, as well as lower levels of uric acid, cholesterol and triglycerides in the PHY + CU group than in the NC. There were significantly fewer oocysts in birds supplemented with additives in the NC group on day 21; on day 35, the NC, PHY and PHY + CU groups had significantly lower counts than the PC and CU groups; however, at 44 days, the lowest counts were in PC group. The bacterial counts were significantly lower on day 21 in all groups that received additives than those of the control group; however, at 44 days, the bacterial and Escherichia coli counts in these groups were significantly higher than those of the control. Curcumin with or without phytogenic agent improved meat quality, with increased antioxidant levels and reduction of lipid peroxidation. There were significantly lower total saturated fatty acid levels and significantly greater monounsaturated/polyunsaturated fatty acid levels in broilers that consumed additives individually and in combination. The combination of additives significantly increased the crypt/villus ratio, a marker of improved intestinal health and performance. Additives potentiated their individual effects, suggesting they can replace conventional growth promoters without compromising health, intestinal mucosa or meat quality.


Assuntos
Acroleína/análogos & derivados , Infecções Bacterianas/veterinária , Coccidiose/veterinária , Curcumina/administração & dosagem , Cimenos/administração & dosagem , Carne/análise , Doenças das Aves Domésticas/prevenção & controle , Timol/administração & dosagem , Acroleína/administração & dosagem , Ração Animal/análise , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Bactérias/isolamento & purificação , Infecções Bacterianas/metabolismo , Infecções Bacterianas/microbiologia , Infecções Bacterianas/fisiopatologia , Galinhas/crescimento & desenvolvimento , Galinhas/metabolismo , Galinhas/microbiologia , Galinhas/parasitologia , Coccídios/efeitos dos fármacos , Coccídios/genética , Coccídios/crescimento & desenvolvimento , Coccidiose/metabolismo , Coccidiose/parasitologia , Coccidiose/prevenção & controle , Suplementos Nutricionais/análise , Ácidos Graxos/química , Ácidos Graxos/metabolismo , Doenças das Aves Domésticas/metabolismo , Doenças das Aves Domésticas/microbiologia , Doenças das Aves Domésticas/parasitologia
2.
Genome Biol Evol ; 9(11): 3108-3121, 2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-29126146

RESUMO

Apicomplexans are successful parasites responsible for severe human diseases including malaria, toxoplasmosis, and cryptosporidiosis. For many years, it has been discussed whether these parasites are in possession of peroxisomes, highly variable eukaryotic organelles usually involved in fatty acid degradation and cellular detoxification. Conflicting experimental data has been published. With the age of genomics, ever more high quality apicomplexan genomes have become available, that now allow a new assessment of the dispute. Here, we provide bioinformatic evidence for the presence of peroxisomes in Toxoplasma gondii and other coccidians. For these organisms, we have identified a complete set of peroxins, probably responsible for peroxisome biogenesis, division, and protein import. Moreover, via a global screening for peroxisomal targeting signals, we were able to show that a complete set of fatty acid ß-oxidation enzymes is equipped with either PTS1 or PTS2 sequences, most likely mediating transport of these factors to putative peroxisomes in all investigated Coccidia. Our results further imply a life cycle stage-specific presence of peroxisomes in T. gondii and suggest several independent losses of peroxisomes during the evolution of apicomplexan parasites.


Assuntos
Evolução Biológica , Coccídios/citologia , Peroxissomos/genética , Toxoplasma/citologia , Coccídios/crescimento & desenvolvimento , Coccídios/metabolismo , Estágios do Ciclo de Vida , Oxirredutases , Peroxissomos/química , Sinais Direcionadores de Proteínas , Proteínas de Protozoários/química , Toxoplasma/crescimento & desenvolvimento , Toxoplasma/metabolismo
3.
J Eukaryot Microbiol ; 61(6): 637-43, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25041145

RESUMO

Cystoisospora felis is a ubiquitous apicomplexan protozoon of cats. The endogenous development of C. felis was studied in cats after feeding them infected mice. For this, five newborn cats were killed at 24, 48, 72, 96, and 120 h after having been fed mesenteric lymph nodes and spleens of mice that were inoculated with C. felis sporulated sporocysts. Asexual and sexual development occurred in enterocytes throughout the villi of the small intestine. The number of asexual generations was not determined with certainty, but there were different sized merozoites. At 24 h, merogony was seen only in the duodenum and the jejunum. Beginning at 48 h, the entire small intestine was parasitized. At 24 h, meronts contained 1-4 zoites, and at 48 h up to 12 zoites. Beginning with 72 h, the ileum was more heavily parasitized than the jejunum. At 96 and 120 h, meronts contained many zoites in various stages of development; some divided by endodyogeny. The multiplication was asynchronous, thus both immature multinucleated meronts and mature merozoites were seen in the same parasitophorous vacuole. Gametogony occurred between 96 and 120 h, and oocysts were present at 120 h. For the study of the development of C. felis in murine tissues, mice were killed from day 1 to 720 d after having been fed 10(5) sporocysts, and their tissues were examined for the parasites microscopically, and by bioassay in cats. The following conclusions were drawn. (1) Cystoisospora felis most frequently invaded the mesenteric lymph nodes of mice and remained there for at least 23 mo. (2) It also invaded the spleen, liver, brain, lung, and skeletal muscle of mice, but division was not seen based on microscopical examination. (3) This species could not be passed from mouse to mouse.


Assuntos
Coccídios/crescimento & desenvolvimento , Animais , Gatos , Coccídios/citologia , Coccídios/ultraestrutura , Coccidiose/veterinária , Estágios do Ciclo de Vida , Camundongos , Oocistos
4.
Ticks Tick Borne Dis ; 4(6): 542-6, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24209494

RESUMO

Hepatozoon canis is a common apicomplexan parasite of dogs. In Brazil, in addition to Rhipicephalus sanguineus, Amblyomma ovale, Amblyomma cajennense, and Rhipicephalus (Boophilus) microplus have been suggested to act as vectors. The present study aimed to evaluate, under controlled conditions, the acquisition of H. canis by A. ovale, R. sanguineus, and A. cajennense after feeding on naturally infected dogs. Cytological and histophatological examinations were performed to recover oocysts and other sporogonic stages of the protozoan from the experimentally infected nymphs and adults. None of the R. sanguineus (n=30) or A. cajennense nymphs (n=15) that were dissected after feeding on H. canis naturally infected dogs became infected by the hemoparasite. Likewise, none of the R. sanguineus (n=165) and A. cajennense (n=114) adult ticks that were fed as nymphs on dogs demonstrated infection. Additionally, A. cajennense adult ticks were incapable of acquiring the infection, since no parasite was found in 62 adults that fed on H. canis-infected dogs. With regard to A. ovale ticks, 2 different infestations were carried out. Firstly, a dog with naturally occurring hepatozoonosis was infested with A. ovale adults originating from Rondônia, Brazil. Ticks fed to full engorgement. A total of 31 adults was collected from the dog and dissected on the third day after natural detachment. Oocysts were detected in 13 (42%) of the ticks. The second experimental infestation was carried out using adult ticks originating from São Paulo, Brazil. Surprisingly, of the 103 dissected ticks, only one (1%) contained oocysts in the hemocoel. No other sporogonic stage was found. Results indicate that different strains of A. ovale ticks may exist in Brazil with different susceptibilities to pathogens. Furthermore, it is possible that R. sanguineus and A. cajennense have little or no importance in the transmission of H. canis in rural areas of Brazil.


Assuntos
Vetores Aracnídeos/parasitologia , Coccídios/isolamento & purificação , Coccidiose/veterinária , Doenças do Cão/transmissão , Ixodidae/parasitologia , Rhipicephalus sanguineus/parasitologia , Animais , Brasil , Coccídios/genética , Coccídios/crescimento & desenvolvimento , Coccidiose/parasitologia , Coccidiose/transmissão , Doenças do Cão/parasitologia , Cães , Feminino , Masculino , Ninfa , Oocistos
5.
Parasitol Res ; 112(7): 2533-42, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23620221

RESUMO

Developmental stages of Hepatozoon seurati (Laveran and Pettit 1911) comb. nov. are described from the tissues of the corned viper Cerastes cerastes, and from the vector Culex pipiens. The parasite described in the present study is firstly recorded as Haemogregarina seurati (Laveran and Pettit 1911) in the same host. After demonstration of the sporogonous development in the mosquito vector (C. pipiens) which showed all characteristics of the genus Hepatozoon (large oocysts containing many sporocysts producing numerous sporozoites), the parasite should be transferred into the genus Hepatozoon. The infected erythrocytes measured 20 ± 0.95 × 7.3 ± 0.85 µm; while uninfected cells measured 13.3 ± 1.04 × 7.5 ± 0.16 µm. Hypertrophy and faintly stained cytoplasm are mostly occurred in infected erythrocytes. Blood stages of the parasite were found exclusively in the erythrocytes in two forms: (1) small trophozoites (10.0 ± 0.52 × 3.0 ± 0.4 µm) and (2) long (mature) sausage-shaped (16.5 ± 1.5 × 3.5 ± 0.4 µm). Merogony occurred in the endothelial cells of the blood capillaries of lung, liver, and spleen. Mature meronts was 27.6 ± 0.7 × 17.5 ± 0.5 µm in diameter and contained 20-35 merozoites (averaged in 26). These merozoites measured 16.5 ± 1.5 × 3.5 ± 0.4 µm. Syzygy and gamogony occurred in the mosquito myxocoel till the 5th day post-infection (p.i.) while sporogony took place after 15 days p.i. On the third day p.i., a large spherical macrogamete of 29.0 ± 0.8 × 20.5 ± 0.6 µm containing a distinct nucleus in association with a single microgamete were observed. The microgamete was pyriform measured 8 ± 02 µm in length. It had a prominent nucleus and a long flagellum of at least 20.4 ± 1.3 µm in length. Fertilization occurred on the 3rd to the 4th days p.i. and the formed zygote developed into an oocyst in which repeated mitotic divisions with centripetal invaginations occurred producing sporoblasts. After sporulation, each sporoblast termed as sporocyst, and contained 18 banana-shaped sporozoites measured 14.0 ± 1.6 × 3.2 ± 0.6 µm. Experimental transmission was successful by intraperitoneal inoculation of the infective stages (sporozoites) to uninfected vipers and led to the appearance of blood stages after 5-6 weeks.


Assuntos
Coccídios/classificação , Coccídios/crescimento & desenvolvimento , Culex/parasitologia , Viperidae/parasitologia , Animais , Coccídios/citologia , Egito , Células Endoteliais/parasitologia , Eritrócitos/parasitologia , Feminino , Masculino , Microscopia
6.
Poult Sci ; 90(7): 1416-26, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21673156

RESUMO

The effectiveness of diatomaceous earth (DE) as a treatment against parasites and to increase feed efficiency and egg production of organically raised free-range layer hens was evaluated in 2 breeds of commercial egg layers [Bovan Brown (BB) and Lowmann Brown (LB)] that differ in their resistance to internal parasitic infections. Half the hens of each breed were fed diets supplemented with DE (2%). Their internal parasite loads were assessed by biweekly fecal egg counts (FEC) and by postmortem examination of the gastrointestinal tract. Supplementing DE in diets of LB hens, the more parasite-resistant breed, did not significantly affect their FEC and adult parasite load. However, BB hens treated with dietary DE had significantly lower Capillaria FEC, slightly lower Eimeria FEC, fewer birds infected with Heterakis, and significantly lower Heterakis worm burden than control BB hens. Both BB and LB hens fed the diet containing DE were significantly heavier, laid more eggs, and consumed more feed than hens fed the control diet, but feed efficiency did not differ between the 2 dietary treatments. Additionally, BB hens consuming the DE diet laid larger eggs containing more albumen and yolk than hens consuming the control diet. In a subsequent experiment, the effectiveness of DE to treat a Northern fowl mite (Ornithonyssus sylviarum) infestation was tested. Relative to controls, both breeds of hens that were dusted with DE had reduced number of mites. The results of this study indicate the DE has the potential to be an effective treatment to help control parasites and improve production of organically raised, free-range layer hens.


Assuntos
Coccídios/crescimento & desenvolvimento , Coccidiose/veterinária , Terra de Diatomáceas/administração & dosagem , Enteropatias Parasitárias/veterinária , Infestações por Ácaros/veterinária , Doenças das Aves Domésticas/prevenção & controle , Doenças das Aves Domésticas/parasitologia , Animais , Galinhas , Coccidiose/parasitologia , Coccidiose/prevenção & controle , Ovos/parasitologia , Fezes/parasitologia , Feminino , Enteropatias Parasitárias/parasitologia , Enteropatias Parasitárias/prevenção & controle , Infestações por Ácaros/parasitologia , Infestações por Ácaros/prevenção & controle , Contagem de Ovos de Parasitas/veterinária , Distribuição Aleatória
7.
Parasitol Res ; 108(4): 845-51, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20972580

RESUMO

Three specimens of Caudisoma durissa terrifica infected with Hepatozoon spp. were studied. One was parasitized by one type of gamont and the other two were each infected by two morphologically different gamonts. Utilizing morphology and morphometry analysis, we concluded that three types of gamonts were very similar and may represent the same Hepatozoon species, but at least three different Hepatozoon species were infecting the C. durissa terrifica snakes in this study. Some of this species caused erythrocyte modifications. The sporogonic development of Hepatozoon sp. was observed from 12 h to the 20th day after female Culex quinquefasciatus blood meals.


Assuntos
Coccídios/crescimento & desenvolvimento , Coccídios/isolamento & purificação , Viperidae/parasitologia , Animais , Biometria/métodos , Coccídios/citologia , Culex/parasitologia , Eritrócitos/parasitologia , Microscopia/métodos
8.
Syst Parasitol ; 75(1): 75-9, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20012520

RESUMO

In Iberian and Canarian lizards, haemogregarines have been recorded infecting erythrocytes, but most of the records correspond to mature gametocytes. We analysed blood smears from 75 specimens of Podarcis bocagei (Seoane) and 33 specimens of P. carbonelli (Pérez-Mellado) from localities of north-western Portugal. We found haemogregarines in 74.7% of P. bocagei and 69.7% of P. carbonelli. Our observations show characteristics of the haemogregarines other than the morphology of the mature gametocytes. In histological sections of the liver of four hosts latent cysts with sporozoites and meronts with merozoites were detected. Both traits have been described as typical of the genera Hepatozoon Miller, 1908 and Hemolivia Petit, Landau, Baccam & Lainson, 1990. We suggest that not only P. bocagei and P. carbonelli from Portugal but other species of Iberian and Canarian lacertids might also be infected by species belonging to one or both genera.


Assuntos
Coccídios/classificação , Coccídios/crescimento & desenvolvimento , Coccidiose/veterinária , Eritrócitos/parasitologia , Estágios do Ciclo de Vida , Lagartos/parasitologia , Animais , Coccídios/isolamento & purificação , Coccidiose/parasitologia , Interações Hospedeiro-Parasita , Fígado/parasitologia , Portugal , Especificidade da Espécie
9.
Folia Parasitol (Praha) ; 56(1): 1-5, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19391326

RESUMO

A series of experiments have been undertaken to determine the effect of water extracts from pine bark (Pinus radiata) on the inhibition of the sporulation of oocysts of three species of avian coccidia. Tubes containing coccidian oocysts isolated from droppings of coccidia-infected chickens were randomly assigned to 0, 250, 500 and 1000 microg/ml pine bark extract (PBE). The tubes were incubated at 25-29 degrees C for 48 h depending on the species of Eimeria. Sporulation inhibition bioassay was used to evaluate the activity of PBE on the sporulation of coccidian oocysts. The oocysts were gently aerated with an air pump away from sun light. The results show for the first time that water-soluble extracts from pine bark containing 35% condensed tannins have anticoccidial activity as evidenced by their ability to decrease significantly the sporulation of the oocysts of three species of Eimeria, namely Eimeria tenella (Railliet et Lucet, 1891), E. maxima Tyzzer, 1929 and E. acervulina Tyzzer, 1929, under laboratory conditions. Incubation of unsporulated oocysts of these parasites in water containing 500 microg PBE per ml resulted in inhibition of sporulation of these oocysts by about 28-84% relative to the oocysts in the control incubations. In addition, up to 12% of E. maxima oocysts exposed to 500-1000 microg pine bark/ml were containing abnormal sporocysts in terms of size, number and shape.


Assuntos
Coccídios/efeitos dos fármacos , Coccídios/crescimento & desenvolvimento , Pinus/química , Casca de Planta/química , Extratos Vegetais/farmacologia , Animais , Oocistos/efeitos dos fármacos , Oocistos/crescimento & desenvolvimento
10.
Parasitology ; 136(12): 1469-75, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19366482

RESUMO

Before the discovery of Toxoplasma gondii as a coccidium of the cat in 1970, cat and dog coccidia were classified in the genus Isospora and considered of little clinical or zoonotic significance. Since 1970, several new (Hammondia sp., Neospora sp.) and previously described species, including Sarcocystis, Besnoitia, and Cryptosporidium have been found as coccidians of cats and dogs with clinical and zoonotic significance. In the present paper I review salient features of the evolution of cat and dog coccidia.


Assuntos
Doenças do Gato/parasitologia , Coccídios , Coccidiose/veterinária , Doenças do Cão/parasitologia , Animais , Gatos , Coccídios/classificação , Coccídios/crescimento & desenvolvimento , Coccídios/isolamento & purificação , Coccídios/patogenicidade , Coccidiose/parasitologia , Cryptosporidium/crescimento & desenvolvimento , Cryptosporidium/isolamento & purificação , Cães , Neospora/crescimento & desenvolvimento , Neospora/isolamento & purificação , Sarcocystidae/crescimento & desenvolvimento , Sarcocystidae/isolamento & purificação , Toxoplasma/crescimento & desenvolvimento , Toxoplasma/isolamento & purificação
11.
Parasitol Int ; 57(3): 287-94, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18329332

RESUMO

Morphological and genetic features of a new Hepatozoon species, Hepatozoon ursi n. sp., in Japanese black bear (Ursus thibetanus japonicus) were studied. Schizogonic developmental stages were observed in the lungs of Japanese black bears. The schizonts were sub-spherical in shape and 45.7+/-4.6 x 42.7+/-4.5 microm in size. Each mature schizont contained approximately 80-130 merozoites and 0-5 residual bodies. The merozoites were 7.0+/-0.7 x 1.8+/-0.3 microm in size. Intraleukocytic gametocytes were slightly curved, cigar-like in shape and had a beak-like protrusion at one end. The size of the gametocytes was 10.9+/-0.3 x 3.3+/-0.2 microm. The analyses of the18S rRNA gene sequences supported the hypothesis that H. ursi n. sp. is different from other Hepatozoon species. Mature Hepatozoon oocysts were detected in two species of ticks (Haemaphysalis japonica and Haemaphysalis flava) collected on the bears infected with H. ursi n. sp. Two measured oocysts were 263.2 x 234.0 microm and 331.8 x 231.7 microm, respectively. The oocysts contained approximately 40 and 50 sporocysts, respectively. The sporocysts were sub-spherical in shape and 31.2+/-2.5 x 27.0+/-2.9 microm in size. Each sporocyst contained at least 8-16 sporozoites, with the sporozoites being 12.2+/-1.4 x 3.5+/-0.5 microm in size. H. ursi n. sp. is the first Hepatozoon species recorded from the family Ursidae.


Assuntos
Coccídios/classificação , Coccídios/crescimento & desenvolvimento , Coccidiose/veterinária , Ursidae/parasitologia , Animais , Coccídios/genética , Coccídios/ultraestrutura , Coccidiose/parasitologia , Coccidiose/patologia , Japão , Pulmão/parasitologia , Pulmão/patologia , Merozoítos/ultraestrutura , Dados de Sequência Molecular , Oocistos/ultraestrutura , Filogenia , RNA Ribossômico 16S/genética , Esquizontes/ultraestrutura , Análise de Sequência de DNA , Especificidade da Espécie , Carrapatos/parasitologia
12.
Parasitol Res ; 102(2): 233-41, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17885764

RESUMO

Obviously, the present study reports the coccidian parasite so-called Goussia cichlidarum for the first time in Egypt. Altogether, 25 exogenous stages were clearly distinguished from specimens of naturally infected fishes of Oreochromis niloticus, O. auraeus, and Tilapia zillii from different locations. The total prevalence of infection was about 41%. Mostly, infected fish grossly seemed with a healthy body, although severe lesions have been detected microscopically in massive infection. Portions of thick wall swim bladder have been placed in vitro. The released parasitic stages have been photographed, sketched, measured, described, and compared with previously described species. Oocysts, sporocysts, and sporozoites have also been differentiated morphologically and morphometrically. Maturity stages of sporozoites containing sporocysts within either an oocyst or those released and sporulated outside the oocyst were considerably discernible. In addition, endogenous stages have also been investigated in histological sections included gamonts, merozoites, oocysts, and different stages of sporozoites.


Assuntos
Sacos Aéreos/parasitologia , Coccídios , Coccidiose/veterinária , Doenças dos Peixes/parasitologia , Interações Hospedeiro-Parasita , Tilápia/parasitologia , Sacos Aéreos/ultraestrutura , Animais , Coccídios/crescimento & desenvolvimento , Coccídios/isolamento & purificação , Coccídios/fisiologia , Coccídios/ultraestrutura , Coccidiose/parasitologia , Egito , Estágios do Ciclo de Vida , Oocistos/crescimento & desenvolvimento , Oocistos/ultraestrutura , Esporos de Protozoários/crescimento & desenvolvimento , Esporos de Protozoários/ultraestrutura , Esporozoítos/crescimento & desenvolvimento , Esporozoítos/ultraestrutura
13.
J Invertebr Pathol ; 96(3): 261-4, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17603071

RESUMO

Aggregata octopiana (Apicomplexa, Aggregatidae) is the most prevalent coccidian in the wild common octopus (Octopus vulgaris), whose heteroxenous life cycle includes gamogony and sporogony undergoing in the octopus digestive tract. In the infected reared octopi, we observed an unusual extraintestinal distribution of the coccidian, with both gamogony and sporogony ongoing in dermal and gill tissue. Oocysts and macrogamonts were embedded in the dermal connective tissue of octopian arms, demarcated by a thin cyst wall or multilayered dark membrane. In gill connective and epithelial tissue all developmental stages were observed, eliciting hemocytic infiltration. Sometimes a complete substitution of the tissue by cysts and developmental stages occurred, resulting in necrosis of gill tissue.


Assuntos
Coccídios/crescimento & desenvolvimento , Coccidiose/veterinária , Octopodiformes/parasitologia , Animais , Estágios do Ciclo de Vida
14.
Exp Parasitol ; 116(4): 375-84, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17399705

RESUMO

The apicoplast is a recently discovered, plastid-like organelle present in most apicomplexa. The methylerythritol phosphate (MEP) pathway involved in isoprenoid biosynthesis is one of the metabolic pathways associated with the apicoplast, and is a new promising therapeutic target in Plasmodium falciparum. Here, we check the presence of isoprenoid genes in four coccidian parasites according to genome database searches. Cryptosporidium parvum and C. hominis, which have no plastid genome, lack the MEP pathway. In contrast, gene expression studies suggest that this metabolic pathway is present in several development stages of Eimeria tenella and in tachyzoites of Toxoplasma gondii. We studied the potential of fosmidomycin, an antimalarial drug blocking the MEP pathway, to inhibit E. tenella and T. gondii growth in vitro. The drug was poorly effective even at high concentrations. Thus, both fosmidomycin sensitivity and isoprenoid metabolism differs substantially between apicomplexan species.


Assuntos
Coccídios/metabolismo , Eritritol/metabolismo , Fosfomicina/análogos & derivados , Terpenos/metabolismo , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Galinhas , Coccídios/efeitos dos fármacos , Coccídios/genética , Coccídios/crescimento & desenvolvimento , Cryptosporidium/efeitos dos fármacos , Cryptosporidium/genética , Cryptosporidium/crescimento & desenvolvimento , Cryptosporidium/metabolismo , Cryptosporidium parvum/efeitos dos fármacos , Cryptosporidium parvum/genética , Cryptosporidium parvum/crescimento & desenvolvimento , Cryptosporidium parvum/metabolismo , Eimeria tenella/efeitos dos fármacos , Eimeria tenella/genética , Eimeria tenella/crescimento & desenvolvimento , Eimeria tenella/metabolismo , Eritritol/genética , Fosfomicina/farmacologia , Regulação da Expressão Gênica no Desenvolvimento/genética , Genoma de Protozoário , Herbicidas/farmacologia , Isoxazóis/farmacologia , Camundongos , Camundongos Endogâmicos CBA , Oxazolidinonas/farmacologia , Toxoplasma/efeitos dos fármacos , Toxoplasma/genética , Toxoplasma/crescimento & desenvolvimento , Toxoplasma/metabolismo
15.
J Parasitol ; 93(1): 89-92, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17436946

RESUMO

Previous studies have described a range of Klossiella species parasitic in marsupial hosts. Klossiella quimrensis is the etiologic agent of renal coccidiosis in the peramelid marsupial hosts Isoodon obesulus and Perameles gunnii in Eastern Australia, but there is no previous report of klossiellosis in Western Australian peramelids. This study describes klossiellosis diagnosed by histology of renal tissue sections collected during necropsy of 20 Perameles bougainville between 2000 and 2005. Sporonts, sporoblasts, and macrogametes were identified within parasitophorous vacuoles of epithelial cells located near the renal corticomedullary junction. The prevalence of renal coccidiosis in P. bougainville diagnosed by renal histology is estimated at 30%. Only a single unsporulated sporocyst was detected by examination of cystocentesis-collected urine, indicating that microscopic evaluation of urine samples is an insensitive diagnostic test for detection of K. quimrensis in P. bougainville. This infection in P. bougainville is indirectly associated with mild multifocal interstitial lymphohistiocytic nephritis and is likely to be only minimally pathogenic in otherwise healthy individuals. Our study also extends the host and geographic range of K. quimrensis to include P. bougainville and Western Australia.


Assuntos
Coccídios/fisiologia , Coccidiose/veterinária , Nefropatias/veterinária , Marsupiais/parasitologia , Animais , Coccídios/crescimento & desenvolvimento , Coccídios/ultraestrutura , Coccidiose/epidemiologia , Coccidiose/parasitologia , Rim/parasitologia , Rim/patologia , Nefropatias/epidemiologia , Nefropatias/parasitologia , Estágios do Ciclo de Vida/fisiologia , Prevalência , Vacúolos/parasitologia , Austrália Ocidental/epidemiologia
16.
J Parasitol ; 93(5): 1189-98, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18163356

RESUMO

Hepatozoon ayorgbor n. sp. is described from specimens of Python regius imported from Ghana. Gametocytes were found in the peripheral blood of 43 of 55 snakes examined. Localization of gametocytes was mainly inside the erythrocytes; free gametocytes were found in 15 (34.9%) positive specimens. Infections of laboratory-reared Culex quinquefasciatus feeding on infected snakes, as well as experimental infection of juvenile Python regius by ingestion of infected mosquitoes, were performed to complete the life cycle. Similarly, transmission to different snake species (Boa constrictor and Lamprophis fuliginosus) and lizards (Lepidodactylus lugubris) was performed to assess the host specificity. Isolates were compared with Hepatozoon species from sub-Saharan reptiles and described as a new species based on the morphology, phylogenetic analysis, and a complete life cycle.


Assuntos
Boidae/parasitologia , Coccídios/classificação , Coccídios/crescimento & desenvolvimento , Coccidiose/veterinária , Culex/parasitologia , Insetos Vetores/parasitologia , Animais , Coccídios/patogenicidade , Coccidiose/parasitologia , Coccidiose/transmissão , DNA de Protozoário/análise , DNA de Protozoário/isolamento & purificação , Eritrócitos/parasitologia , Estágios do Ciclo de Vida , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Especificidade da Espécie
17.
J Egypt Soc Parasitol ; 37(3 Suppl): 1199-212, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18431994

RESUMO

The bean skink lizard Mabuya quinquetaeniata quinquetaeniata (Family: Scincidae) collected from Abu-Rawash, Giza was infected with the protozoon Hepatozoon gracilis. The mean percent of infection rate all over the year was 12.57% with the highest peak was in October (33%), meanwhile the lowest infection rate was detected in June (2.1%) and no infection was detected in February. Microscopical examination of experimentally infected Culex (C.) pipiens L smears revealed the presence of gamogony and sporogony stages of H. gracilis in their haemoceal. Cx. pipiens was capable to transmit H. gracilis to non-infected M. q. quinquetaeniata under laboratory conditions (21 +/- 1 & 60-70% R.H) after a prepatent period of 32 +/- 1 days from the infective bite. Various developmental schizogony stages were detected both in the lung endothelial cells and liver parenchymal cells. Developmental stages of H. gracilis in both vector or vertebrate host were described. Cx. pipiens was unable to transmit H. gracilis to snake, Psammophis schokari present in the same area of the bean skink lizard.


Assuntos
Coccídios/crescimento & desenvolvimento , Coccidiose/transmissão , Culex/parasitologia , Insetos Vetores/parasitologia , Lagartos/parasitologia , Animais , Mordeduras e Picadas , Egito , Humanos , Estágios do Ciclo de Vida , Estações do Ano
18.
J Wildl Dis ; 42(2): 386-90, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16870862

RESUMO

In searching for an invertebrate host for Hepatozoon sp. infecting the montane vole (Microtus montanus), we collected fleas, ticks, and mites from live-trapped voles and searched squash preparations for Hepatozoon oocysts. From 1989 through 1996, we identified six species of fleas in Grand Teton National Park: Megabothris abantis, Megabothris asio megacolpus, Aetheca wagneri, Peromyscopsylla selenis, Peromyscopsylla. hesperomys, and Hystrichopsylla dippiei dippiei. We found Hepatozoon oocysts only in M. abantis; we found no oocysts in mites or ticks. We conclude that M. abantis is an invertebrate host of Hepatozoon sp. and is likely to be the definitive host for theHepatozoon spp. of M. montanus.


Assuntos
Arvicolinae/parasitologia , Coccídios/crescimento & desenvolvimento , Coccidiose/veterinária , Sifonápteros/parasitologia , Animais , Coccídios/isolamento & purificação , Coccidiose/transmissão , Reservatórios de Doenças/veterinária , Interações Hospedeiro-Parasita , Montana/epidemiologia , Oocistos/isolamento & purificação , Especificidade da Espécie
19.
J Egypt Soc Parasitol ; 36(1): 241-50, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16605113

RESUMO

A successful experimental infection of Psammophis schokari snake with Hepatozoon matruhensis through Culex (Culex) pipiens bites was carried out under laboratory condition of 20 +/- 1 degrees C and 60-70 % R.H. The period monitored for gametocyte maturation ranged from 38 to 42 days while the recorded prepatent period ranged from 28 to 35 days. The effect of infection was nonsignificant on longevity, incubation period and percenttage of egg hatching (P>0.05). Meanwhile a significant increase (P<0.05) in the preoviposition period together with a significant reduction (P<0.001) in the number of eggs deposited of infected females were recorded.


Assuntos
Coccídios/crescimento & desenvolvimento , Coccidiose/veterinária , Culex/parasitologia , Insetos Vetores/parasitologia , Serpentes/parasitologia , Animais , Mordeduras e Picadas , Coccidiose/parasitologia , Coccidiose/transmissão , Egito , Feminino , Temperatura , Fatores de Tempo
20.
J Egypt Soc Parasitol ; 36(1): 251-8, following 258, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16605114

RESUMO

Laboratory observations revealed that both C. pipiens and C. quinquefasciatus could harbour the parasitic Hepatozoon, while only Cx. pipiens succeeded to induce infection to the recipient lizard Uromastyx microlepis. A significant reduction in egg production together with a significant increase in the pre-oviposition period of C. pipiens was recorded. Incubation period and percentage of egg hatching showed no significant changes. Infection had no effect on the reproductive fitness of C. quinquefasciatus. Haematin excretion was normally distributed for all both species. No size difference was recorded between infected and uninfected ones. Infection did not affect longevity.


Assuntos
Coccídios/crescimento & desenvolvimento , Coccidiose/veterinária , Culex/parasitologia , Insetos Vetores/parasitologia , Lagartos/parasitologia , Animais , Coccidiose/parasitologia , Coccidiose/transmissão , Egito , Feminino , Longevidade , Oviposição
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