RESUMO
The purpose of this pilot study was to evaluate and determine the concentration of prostaglandin GF2α (PGF2α) and isoprostane 8-iso-PGF2α in plasma and intestine of specific pathogen-free (SPF) Leghorn chickens challenged with Eimeria maxima, with or without dietary supplementation of curcumin using solid-phase microextraction and ultra-performance liquid chromatography/tandem mass spectrometry. Eighty 1-day-old male SPF chickens were randomly allocated to one of four groups with four replicates (n = 5 chickens/replicate). Groups consisted of: (1) Control (no challenge), (2) Curcumin (no challenge), (3) Eimeria maxima (challenge), and (4) Eimeria maxima (challenge) + curcumin. At day 28 of age, all chickens in the challenge groups were orally gavaged with 40,000 sporulated E. maxima oocysts. No significant differences (P > 0.05) were observed in the groups regardless of the treatment or challenge with E. maxima. Enteric levels of both isoprostane 8-iso-PGF2α and PGF2α at 7 days and 9 days post-challenge were significantly increased (P < 0.01) compared to the non-challenge control chickens. Interestingly, the enteric levels of both isoprostane 8-iso-PGF2α and PGF2α at 7 days post-challenge were significantly reduced in chickens fed curcumin, compared to control chickens challenge with E. maxima. At 9 days post-challenge, only levels of isoprostane 8-iso-PGF2α in the enteric samples were significantly reduced in chickens challenged with E. maxima supplemented with curcumin, compared with E. maxima challenge chickens. No differences of isoprostane 8-iso-PGF2α or PGF2α were observed in plasma at both days of evaluation. Similarly, no significant differences were observed between the challenge control or chickens challenge with E. maxima and supplemented with curcumin at both times of evaluation. The results of this pilot study suggests that the antioxidant anti-inflammatory properties of curcumin reduced the oxidative damage and subsequent intestinal mucosal over-production of lipid oxidation products. Further studies to confirm and extend these results in broiler chickens are required.
Assuntos
Anti-Inflamatórios/farmacologia , Coccidiose/tratamento farmacológico , Curcumina/farmacologia , Dinoprosta/análogos & derivados , Dinoprosta/antagonistas & inibidores , Eimeria/efeitos dos fármacos , Doenças das Aves Domésticas/tratamento farmacológico , Ração Animal , Animais , Animais Recém-Nascidos , Galinhas/crescimento & desenvolvimento , Galinhas/parasitologia , Coccidiose/metabolismo , Coccidiose/parasitologia , Coccidiose/veterinária , Suplementos Nutricionais , Dinoprosta/metabolismo , Eimeria/crescimento & desenvolvimento , Eimeria/patogenicidade , Inflamação , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/parasitologia , Masculino , Oocistos/efeitos dos fármacos , Oocistos/crescimento & desenvolvimento , Oocistos/patogenicidade , Estresse Oxidativo , Doenças das Aves Domésticas/metabolismo , Doenças das Aves Domésticas/parasitologia , Organismos Livres de Patógenos EspecíficosRESUMO
Eimeria zuernii and E. bovis are host-specific apicomplexan parasites of cattle causing haemorrhagic typhlocolitis in young animals worldwide. During first merogony, both Eimeria species form giant macromeronts (>300⯵m) in host endothelial cells containing >120,000 merozoites I in vivo. During the massive intracellular replication of macromeronts, large amounts of cholesterol and fatty acids are indispensable for enormous merozoite I-derived membrane production. From a metabolic perspective, host endothelial cells might be of advantage to the parasite, as transcription of several genes involved in both, cholesterol de novo biosynthesis and low density lipoprotein (LDL)-mediated uptake, are up-regulated in Eimeria macromeront-carrying host endothelial cells. In order to analyse further influence of E. zuernii/E. bovis infections on the metabolism of cholesterol, fatty acids, and glycolysis of the host endothelial cells, suitable in vitro cell culture systems are necessary. So far, in vitro cell culture systems based on primary bovine umbilical vein endothelial cells (BUVEC) are available for E. bovis-macromeront I formation, but have not been evaluated for E. zuernii. A novel E. zuernii (strain A), initially isolated from naturally infected calves in Antioquia, Colombia, was used for sporozoite isolation. Primary BUVEC monolayers were concomitantly infected with E. zuernii- and E. bovis-sporozoites, resulting in large sized macromeronts whose morphological/morphometric characteristics were compared. BUVEC carrying E. zuernii-macromeronts resulted in the release of viable and highly motile merozoites I. Overall, E. zuernii-merozoites I differed morphologically from those of E. bovis. The new E. zuernii (strain A) will allow detailed in vitro investigations not only on the modulation of cellular cholesterol processing (i. e. cholesterol-25-hydroxylase and sterol O-acyltransferase) but also on the surface expression of LDL receptors during macromeront formation.
Assuntos
Doenças dos Bovinos/parasitologia , Coccidiose/veterinária , Eimeria/crescimento & desenvolvimento , Células Endoteliais/parasitologia , Técnicas In Vitro/métodos , Animais , Bovinos , Coccidiose/parasitologia , Eimeria/citologia , Eimeria/fisiologia , Merozoítos/citologia , Merozoítos/crescimento & desenvolvimento , Merozoítos/fisiologia , Esporozoítos/citologia , Esporozoítos/crescimento & desenvolvimento , Esporozoítos/fisiologiaRESUMO
The endogenous life cycle of Eimeria caliginosa was studied in experimentally infected dusky rice rats, Melanomys caliginosus. All endogenous stages were located in the epithelial cells of villi in the small intestine. Both Giemsa-stained mucosal scrapings and histological sections were studied for the diagnosis of all the life-cycle stages. Eimeria caliginosa has 3 generations of meronts (M) that differ by size, shape, and number of merozoites (m), which also differ in their size, shape, and location of their nuclei within the cytoplasm of the meronts. The 3 meront types, M1-M3, respectively, had 20-33 (m1), 5-9 (m2), and 13-16 (m3) merozoites. Macrogametocytes and microgametocytes, as well as macrogametes and microgametes, completed the sexual cycle, which concludes with the formation of unsporulated oocysts. This parasite's endogenous development produced severe intestinal lesions in the experimentally infected dusky rice rats. In our ongoing work to understand the biodiversity present in plants and animals of the protected Reserva Biológica Alberto Manuel Brenes (ReBAMB) field station in Costa Rica, we now have discovered 3 new Eimeria species, and this is the second complete life cycle in which we document both the asexual and sexual stages.
Assuntos
Coccidiose/veterinária , Eimeria/crescimento & desenvolvimento , Intestino Delgado/parasitologia , Estágios do Ciclo de Vida , Doenças dos Roedores/parasitologia , Sigmodontinae/parasitologia , Animais , Coccidiose/epidemiologia , Coccidiose/parasitologia , Costa Rica/epidemiologia , Enteropatias Parasitárias/epidemiologia , Enteropatias Parasitárias/parasitologia , Enteropatias Parasitárias/veterinária , Mucosa Intestinal/parasitologia , Doenças dos Roedores/epidemiologiaRESUMO
Endogenous stages of the life cycle of Eimeria melanomytis, infecting the peripheral epithelial cells of villi of the small intestine of experimentally infected young dusky rice rats, Melanomys caliginosus , were studied. Giemsa-stained mucosal scrapings and histological sections were examined for all the stages. Eimeria melanomytis has 3 generations of meronts (M), different in size, shape, and number of merozoites (m); and in size, shape, and location of the nuclei within the cytoplasm of the meronts. The 3 meront types, M1-M3, respectively, had 11-14 (m1), 7-10 (m2), and 20-30 (m3) merozoites. Macrogametocytes and microgametocytes, as well as macrogametes and microgametes, complete the sexual cycle forming the unsporulated oocysts. This parasite's endogenous development produced severe intestinal lesions in experimentally infected dusky rice rats.
Assuntos
Coccidiose/veterinária , Eimeria/crescimento & desenvolvimento , Estágios do Ciclo de Vida , Doenças dos Roedores/parasitologia , Sigmodontinae/parasitologia , Animais , Coccidiose/parasitologia , Costa Rica , Eimeria/isolamento & purificação , Eimeria/fisiologia , Fezes/parasitologia , Intestino Delgado/parasitologia , Intestino Delgado/ultraestrutura , Merozoítos , Microvilosidades/parasitologia , Oocistos , Esporos de Protozoários , TrofozoítosRESUMO
The endogenous life cycle of Eimeria marmosopos was studied in experimentally infected young opossums, Didelphis marsupialis . All the endogenous stages were located in the epithelial cells of villi in the small intestine. Giemsa-stained mucosal scrapings and histological sections were studied for the diagnosis of all the life cycle stages. Eimeria marmosopos has 3 generations of meronts (M) that differ by size, shape, and number of merozoites (m), which also differ in their size, shape, and location of their nuclei within the cytoplasm of the meronts. The 3 meront types, M(1)-M(3), respectively, had 8-15 (m(1)), 4-9 (m(2)), and 22-30 (m(3)) merozoites. Macrogametocytes and microgametocytes, as well as macrogametes and microgametes, completed the sexual cycle, finishing with the formation of unsporulated oocysts. This parasite's endogenous development produced severe intestinal lesions in experimentally infected opossums. There are 56 Eimeria species known from all marsupials worldwide, but this is the first complete life cycle in which both the asexual and sexual stages have been documented.
Assuntos
Coccidiose/veterinária , Didelphis/parasitologia , Eimeria/crescimento & desenvolvimento , Estágios do Ciclo de Vida , Animais , Coccidiose/parasitologia , Costa Rica , Eimeria/fisiologia , Fezes/parasitologia , Intestinos/parasitologia , Esporos de ProtozoáriosRESUMO
Coccidiosis of the domestic fowl is a worldwide disease caused by seven species of protozoan parasites of the genus Eimeria. The genome of the model species, Eimeria tenella, presents a complexity of 55-60MB distributed in 14 chromosomes. Relatively few studies have been undertaken to unravel the complexity of the transcriptome of Eimeria parasites. We report here the generation of more than 45,000 open reading frame expressed sequence tag (ORESTES) cDNA reads of E. tenella, Eimeria maxima and Eimeria acervulina, covering several developmental stages: unsporulated oocysts, sporoblastic oocysts, sporulated oocysts, sporozoites and second generation merozoites. All reads were assembled to constitute gene indices and submitted to a comprehensive functional annotation pipeline. In the case of E. tenella, we also incorporated publicly available ESTs to generate an integrated body of information. Orthology analyses have identified genes conserved across different apicomplexan parasites, as well as genes restricted to the genus Eimeria. Digital expression profiles obtained from ORESTES/EST countings, submitted to clustering analyses, revealed a high conservation pattern across the three Eimeria spp. Distance trees showed that unsporulated and sporoblastic oocysts constitute a distinct clade in all species, with sporulated oocysts forming a more external branch. This latter stage also shows a close relationship with sporozoites, whereas first and second generation merozoites are more closely related to each other than to sporozoites. The profiles were unambiguously associated with the distinct developmental stages and strongly correlated with the order of the stages in the parasite life cycle. Finally, we present The Eimeria Transcript Database (http://www.coccidia.icb.usp.br/eimeriatdb), a website that provides open access to all sequencing data, annotation and comparative analysis. We expect this repository to represent a useful resource to the Eimeria scientific community, helping to define potential candidates for the development of new strategies to control coccidiosis of the domestic fowl.
Assuntos
Eimeria/genética , Perfilação da Expressão Gênica , Aves Domésticas/parasitologia , Animais , Análise por Conglomerados , Eimeria/crescimento & desenvolvimento , Eimeria/isolamento & purificação , Etiquetas de Sequências Expressas , Dados de Sequência Molecular , Análise de Sequência de DNARESUMO
A new species of Eimeria Schneider, 1875 from a cracid bird, Mitu tuberosum Spix, held in captivity is described from Brazil. Oöcysts of Eimeria abmitu n. sp. are ovoid, with a smooth, colourless, bilayered wall, measure 24.2 × 15.5 µm and have a length/width ratio of 1.56. The sporulated oöcysts contain two to five polar granules and four ellipsoidal sporocysts measuring 13.6 × 6.4 µm, each with a small crescent-shaped Stieda body, a sub-Stieda body, a loosely granular sporocyst residuum and two comma-shaped sporozoites each with a spherical refractile body.
Assuntos
Eimeria/classificação , Eimeria/isolamento & purificação , Galliformes/parasitologia , Animais , Eimeria/citologia , Eimeria/crescimento & desenvolvimento , Fezes/parasitologia , Oocistos/citologiaRESUMO
Purposing to investigate the betaine effect on biology and morphology of developmental stages of Eimeria acervulina, 420 broiler chicks Cobb were experimentally inoculated with 2 x 10(5) sporulated oocysts and housed in battery cages in a block design with five treatments and six replicates each, including a positive control, a group treated with salinomycin and growth promoter plus three levels of betaine as additive in the feed at 0.05, 0.10 and 0.15%. Measurements of oocysts, sporocysts and endogenous stages were performed as morphological parameters, while pre patent and patent periods and sporulation time were taken as biological parameters. Morphology was also associated with the mathematical constant Phi (1.618) to evaluate possible relationship. Betaine was able to cause modifications in both biology and morphology of oocysts and sporocysts, whereas it was weakly able to affect developmental stages based on trophozoites and macrogamonts measurements. According to the measures of sporocysts E. acervulina development was closely related to Phi.
Assuntos
Betaína/farmacologia , Eimeria/efeitos dos fármacos , Eimeria/crescimento & desenvolvimento , Animais , Galinhas/parasitologia , Estágios do Ciclo de VidaRESUMO
Precocious lines of Eimeria acervulina "Cu" and "I" strains were obtained after 25 passages of oocysts in chickens that showed a shortening of the prepatent period for first oocyst output from 96 h to 81 and 82 h, respectively. Both precocious lines were evaluated for pathogenicity using as criteria weight gain, lesion score and total oocyst production. Infection of the "Cu" precocious line in chickens showed a high weight gain, low lesion score and low oocyst production, when compared to parent strain infected chickens. However, the results did not show a significant difference in relation to the criteria used above for the E. acervulina "I" precocious line when compared to its parent strain. This suggests a low degree of attenuation for the "I" strain but good attenuation for the precocious "Cu" line. The histopathological observations of chickens infected with the E. acervulina "Cu" parent strain and precocious line, comparing life cycle and intestinal lesions, showed: (1) parasite stages only in the border cells of infected chicken intestinal villi, for the precocious line; (2) parasite stages in the border cells of the intestinal villi and submucosa cells near the Lieberkühn glands of the intestine; and (3) high degree of inflammatory cells around the parasites in chickens infected with the parent strain. The "Cu" strain was also characterized for sensitivity against eight anticoccidial drugs. Sensitivity was observed for four anticoccidial drugs and partial resistance for four other drugs, although the strain had never had previous contact with anticoccidial drugs, suggesting the presence of a natural resistance factor. This Brazilian E. acervulina "Cu" precocious line showed attenuation for pathogenicity in chickens, suggesting that it could be a suitable strain for use as a live vaccine in Brazil.
Assuntos
Galinhas , Coccidiose/veterinária , Eimeria/crescimento & desenvolvimento , Enteropatias Parasitárias/veterinária , Doenças das Aves Domésticas/parasitologia , Animais , Peso Corporal , Brasil , Coccidiose/imunologia , Coccidiose/parasitologia , Coccidiose/patologia , Coccidiostáticos/farmacologia , Resistência a Medicamentos , Eimeria/metabolismo , Eimeria/patogenicidade , Fezes/parasitologia , Histocitoquímica/veterinária , Enteropatias Parasitárias/imunologia , Enteropatias Parasitárias/parasitologia , Enteropatias Parasitárias/patologia , Intestinos/imunologia , Intestinos/parasitologia , Intestinos/patologia , Contagem de Ovos de Parasitas/veterinária , Doenças das Aves Domésticas/imunologia , Doenças das Aves Domésticas/patologia , Distribuição Aleatória , Organismos Livres de Patógenos Específicos , VirulênciaRESUMO
This study reports the development of a novel multiplex PCR assay based on SCAR (Sequence-Characterised Amplified Region) markers for the simultaneous diagnosis of the 7 Eimeria species that infect domestic fowl. Primer pairs specific for each species were designed in order to generate a ladder of amplification products ranging from 200 to 811 bp. Sensitivity tests for each species were carried out, showing a detection threshold of 1-5 pg, which corresponds approximately to 2-8 sporulated oocysts. Distinct isolates of the 7 Eimeria species from different geographical sources were tested and successfully detected by the assay. All the species were amplified homogeneously, whether or not one of them was present in a high quantity, indicating that there was no cross-interference. The assay was also tested with different sources of Taq DNA polymerase and thermocycler models, confirming the high reproducibility of the reaction. The economy of consumables and labour represented by a single-tube reaction greatly facilitates the molecular diagnosis of a large number of samples, making it appropriate for field epizootiological surveys. We propose the use of this multiplex PCR assay as a rapid and cost-effective diagnostic method for the detection and discrimination of the 7 Eimeria species that infect domestic fowl.
Assuntos
Galinhas , Coccidiose/veterinária , Eimeria/genética , Reação em Cadeia da Polimerase/veterinária , Doenças das Aves Domésticas/parasitologia , Animais , Coccidiose/diagnóstico , Coccidiose/parasitologia , DNA de Protozoário/química , DNA de Protozoário/genética , Eimeria/crescimento & desenvolvimento , Marcadores Genéticos , Variação Genética , Reação em Cadeia da Polimerase/instrumentação , Reação em Cadeia da Polimerase/métodos , Técnica de Amplificação ao Acaso de DNA Polimórfico/veterinária , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
Eimeria carmelinoi n.sp., is described in the teiid lizard Kentropyx calcarata Spix, 1825 from north Brazil. Oocysts subspherical to spherical, averaging 21.25 x 20.15 micro m. Oocyst wall smooth, colourless and devoid of striae or micropyle. No polar body or conspicuous oocystic residuum, but frequently a small number of fine granules in Brownian movement. Sporocysts, averaging 10.1 x 9 microm, are without a Stieda body. Endogenous stages characteristic of the genus: intra-cytoplasmic, within the epithelial cells of the ileum and above the host cell nucleus. A re-description is given of a parasite previously described as Eimeria cnemidophori, in the teiid lizard Cnemidophorus lemniscatus lemniscatus. A study of the endogenous stages in the ileum necessitates renaming this coccidian as Acroeimeria cnemidophori (Carini, 1941) nov.comb., and suggests that Acroeimeria pintoi Lainson & Paperna, 1999 in the teiid Ameiva ameiva is a synonym of A. cnemidophori. A further intestinal coccidian, Acroeimeria paraensis n.sp. is described in C. l. lemniscatus, frequently as a mixed infection with A. cnemidophori. Mature oocysts, averaging 24.4 x 21.8 microm, have a single-layered, smooth, colourless wall with no micropyle or striae. No polar body, but the frequent presence of a small number of fine granules exhibiting Brownian movements. Sporocysts 9 x 8, without a Stieda body. Endogenous stages epicytoplasmic, characteristic of the genus, in the upper ileum. The importance of a study of the endogenous stages of eimeriid coccidia is discussed.
Assuntos
Eimeria/classificação , Lagartos/parasitologia , Animais , Brasil , Eimeria/citologia , Eimeria/crescimento & desenvolvimento , Fezes/parasitologia , OócitosRESUMO
In the present work, we describe the discovery of PW2, a novel peptide presenting in vitro activity against Eimeria acervulina and E. tenella sporozoites. PW2 was selected from phage display (Ph.D.) peptide libraries by an alternative method of panning using living purified E. acervulina sporozoites as targets. Our results showed that the peptide disrupts the sporozoite pellicle, resembling the effect caused by most natural antimicrobial peptides. PW2 peptide was also effective against fungi and showed low activity against Toxoplasma gondii tachyzoites, but no activity against Trypanosoma cruzi, Crithidia fasciculata epimastigotes, and bacteria. Additionally, the parasiticidal concentrations of PW2 produced a very low lytic effect on mammalian and avian cells. The effectiveness against Eimeria sporozoites and the absence of adverse effects to host cells indicates that PW2 may be used as a model to generate new drugs for the control of avian coccidiosis.
Assuntos
Permeabilidade da Membrana Celular/efeitos dos fármacos , Galinhas/parasitologia , Coccidiostáticos/farmacologia , Eimeria/efeitos dos fármacos , Biblioteca de Peptídeos , Peptídeos/farmacologia , Sequência de Aminoácidos , Animais , Células Cultivadas , Eimeria/crescimento & desenvolvimento , Eimeria/patogenicidade , Eritrócitos , Hemólise , Humanos , Peptídeos e Proteínas de Sinalização Intercelular , Rim/citologia , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Testes de Sensibilidade Parasitária , Peptídeos/genética , CoelhosRESUMO
Of 163 fecal samples collected between March 1997 and February 1999 from the plains vizcacha, Lagostomus maximus (Rodentia: Chinchillidae), 19 (12%) were found to be positive for coccidia. All species are from the genus Eimeria and 2 are described here as new. The third species is consistent with the description of Eimeria chinchillae De Vos and Van der Westhuizen, 1968. Sporulated oocysts of Eimeria lagostomi n. sp. are ellipsoidal to subspheroidal, 35.7 x 30.9 (26-36 x 30-41), with a length:width (L/W) ratio of 1.2 (1.0-1.3), without a micropyle (M) or polar granule (PG), but with an oocyst residuum (OR) comprised of a round, compact mass of many small granules. The sporocysts are lemon-shaped, 14.2 x 10.2 (9-11 x 11-16), with an L/W ratio of 1.4 (1.2-1.7) and have a Stieda body (SB) and sporocyst residuum (SR). Eimeria vizcacho n. sp. has sporulated oocysts that are subspheroidal, 26.4 x 23.4 (21-27 x 23-31), with an L/W ratio of 1.1 (1.1-1.2), lack an M and OR, but have 1-2 PGs. Sporocysts are elongate-ellipsoidal, 14.3-9.0 (8-10 x 13-15), with an L/W ratio of 1.6 (1.4-1.8), lack an SB, but have 2 SR; the first a small mass of granules lying between the sporozoites in the middle or at 1 end, and the second also of many small granules, always at the opposite end. Sporulated oocysts of the E. chinchillae-like organism are ellipsoidal to subspheroidal, 20.7 x 17.5 (15-22 x 17-24) with an L/W ratio of 1.2 (1.0-1.3), lack an M and OR, but have 0-3 PGs. Sporocysts are ellipsoidal, 10.7-6.9 (6-8 x 8-13) with an L/W ratio of 1.55 (1.3-1.8) and have an SB and SR.
Assuntos
Coccidiose/veterinária , Eimeria/classificação , Eimeria/crescimento & desenvolvimento , Roedores/parasitologia , Animais , Argentina , Coccidiose/parasitologia , Eimeria/ultraestrutura , Doenças dos Roedores/parasitologiaRESUMO
The endogenous development of Eimeria minasensis was studied in 9 coccidia-free goat kids inoculated with 10(5) sporulated oocysts/kg body weight. Kids were killed 4, 7 (2 animals), 10, 13, 16, 18, 19, and 22 days after inoculation (DAI). In tissue sections of the intestines stained with hematoxylin and eosin and examined by light microscopy, 2 generations of meronts, gamonts, gametes, and oocysts were found. The first generation of meronts developed in cells deep in the lamina propria of the jejunum and ileum. Mature giant meronts (299.4x243.8 microm) found 16 DAI were visible to the naked eye and contained a large number of crescent-shaped merozoites. The second generation of meronts developed in the epithelial cells of crypts of the ileum and above the host cell nuclei. Mature meronts (11.5x10.1 microm) with 18-28 comma-shaped merozoites were first seen 16 DAI. Gametogenesis took place in epithelial cells of the crypts and villi of the terminal part of the ileum, cecum, and colon. Macrogametes (27.8x17.6 microm), mature microgamonts (21.3x17.0 microm), microgametes, and oocysts (30.5x19.4 microm) were found 19 DAI. Sexual stages were below the host cell nucleus.
Assuntos
Coccidiose/veterinária , Eimeria/crescimento & desenvolvimento , Doenças das Cabras/parasitologia , Enteropatias Parasitárias/veterinária , Intestino Delgado/parasitologia , Animais , Brasil , Coccidiose/parasitologia , Células Epiteliais/parasitologia , Cabras , Enteropatias Parasitárias/parasitologia , Organismos Livres de Patógenos EspecíficosRESUMO
The ultrastructure of intracytoplasmic meronts and macrogamonts of Eimeria s.l. boveroi in the small intestine of the gekkonid lizard Hemidactylus mabouia from Belem, Para north Brazil is described. Young meronts, and some of the fully grown macrogamonts, are coated with a glycocalyx which, in cross-section, has the appearance of a series of fine tubules. The wall of the parasitophorous vacuole (PV) is a single membrane, lined on the host-cytoplasm side with an endoplasmic reticulum (ER) which sometimes expands into large cisternae filled with electron-lucent, globular material. The membranal edges of the ER, canaliculi and cisternae have regularly spaced indentations filled with an electron-dense substance. Vesicular mitochondria are present in addition to those of the conventional type. Macrogamonts develop the characteristic type 1 and type 2 wall-forming bodies, and in some zygotes the cisternae containing the latter are grossly expanded. Both types of wall-forming bodies persist in young oocysts that have a distinct oocyst wall.
Assuntos
Eimeria/ultraestrutura , Intestino Delgado/parasitologia , Lagartos/parasitologia , Animais , Eimeria/crescimento & desenvolvimento , Mucosa Intestinal/parasitologia , Estágios do Ciclo de Vida , Microscopia EletrônicaRESUMO
Faecal samples collected from 300 Bolivian marsupials (Didelphimorphia: Didelphidae) between 1984 and 1993 were examined for coccidian parasites. Sporulated oocysts were present in the faeces of 50 (17%) marsupials representing 11 genera and 22 species. Three new species of Eimeria are described and named from six host species. One species occurred in Marmosops dorothea, Monodelphis domestica and Thylamys venustus, another in Micoureus constantiae constantiae and Micoureus constantiae budini and a third in Marmosops dorothea. A discriminant analysis performed on five quantitative oocyst measurements revealed similarities between the first and third Eimeria species because of similar sizes and shapes of the oocysts, whereas the second Eimeria species was structurally discrete. The Eimeria that infects multiple hosts may be a common widespread species. Future surveys are advised for a thorough assessment of the coccidian biodiversity within Bolivian marsupials.
Assuntos
Coccidiose/veterinária , Eimeria/classificação , Eimeria/isolamento & purificação , Gambás/parasitologia , Animais , Bolívia/epidemiologia , Coccidiose/epidemiologia , Coccidiose/parasitologia , Eimeria/crescimento & desenvolvimento , Fezes/parasitologia , Gambás/classificaçãoRESUMO
The oocyst is described of Eimeria peltocephali n.sp. from faeces of the freshwater turtle Peltocephalus dumerilianus from Barcelos, State of Amazonas, Brazil. Sporulation is exogenous and fully developed oocysts are elongate, ellipsoidal or cylindrical, frequently curved to a banana-shape, 54.4 x 19.1 (37.5-68.7 x 18.7-20.0 microns), shape-index 2.8 (1.8-3.9). The oocyst wall is a single thin, colourless layer about 1 micron thick, with no micropyle. There is a bulky oocyst residuum, at first spherical to ellipsoidal, 19 x 16 (16.2-26.2 x 16-21.5 microns), but becoming dispersed on maturation. There are no polar bodies. The sporocysts, 19.1 x 6.8 (17.5-21.2 x 6.2-7.5 microns), shape-index 2.8 (2.3-3.2), are usually disposed in pairs at each end of the oocyst, and bear an inconspicuous Stieda body in the form of a flat cap. The sporozoites are elongate and slightly curved around the residuum. No refractile bodies were seen. Eimeria molossi n.sp., is described from the molossid bat Molossus ater. Sporulation is exogenous and the mature oocysts are predominantly broadly ellipsoidal, 23.4 x 17.5 (18-30 x 15-22.5 microns), shape-index 1.3 (1-1.6). The oocyst wall is about 2 microns thick, and of three layers: an inner thin, colourless one and two outer layers which are thicker, yellowish-brown, prominently striated and in close apposition. There is no micropyle or oocyst residuum, but one and occasionally two polar bodies are usually present. Sporocysts are ellipsoidal, 10.2 x 7.5 (10-12.5 x 7.5 microns), shape-index 1.4 (1.3-1.7) with an inconspicuous Stieda body. Endogenous stages are described in the epithelial cells of the small intestine.
Assuntos
Quirópteros/parasitologia , Eimeria/crescimento & desenvolvimento , Tartarugas/parasitologia , Animais , Brasil , Eimeria/citologia , Fezes , Formaldeído , Intestino Delgado , Microtomia , Dicromato de Potássio , Esporos , Fixação de TecidosRESUMO
Three new species of Eimeria are described from iguanid lizards of Central and South America. The oocysts of each species have no micropyles or residua and the sporocysts lack Stieda bodies, but all have a sporocyst residuum. Eimeria sanctaluciae n.sp. was found in the St. Lucia tree lizard, Anolis luciae, collected from the Maria Islands, Lesser Antilles. The oocysts are spherical to subspherical, averaging 17.3 x 16.5 microns, with a single layered colourless wall; about 60% contain polar granules. The sporocysts are ellipsoidal and average 7.7 x 5.5 microns. Eimeria liolaemi n.sp. was recovered from the blue-gold swift, Liolaemus taenius, from Chile. The oocysts are spherical to subspherical, measuring 21 x 20.1 microns with a single-layered colourless wall. The sporocysts are subspherical and average 7.4 x 6.8 microns. Eimeria caesicia n.sp. is described from the Brazilian collared iguanid, Tropidurus torquatus. The oocysts measure 27.4 x 23.7 microns, are spherical to subspherical, with a bilayered wall, the outer surface of which appears pale blue in colour, the thin, inner wall appearing brown, when viewed by direct light under the optical microscope. The sporocysts are subspherical and average 9.4 x 7.2 microns. Unnamed polysporocystid oocysts with dizoic sporocysts are reported from the faeces of the lesser St. Vincent tree lizard, Anolis trinitatis and the possibility of spurious parasitism briefly discussed. In addition, oocysts of an unnamed Isospora sp. with a smooth oocyst wall which closely resembles I. reui were recovered from A. trinitatis.
Assuntos
Coccidiose/veterinária , Eimeria/isolamento & purificação , Iguanas/parasitologia , Animais , América Central , Eimeria/classificação , Eimeria/crescimento & desenvolvimento , América do SulRESUMO
Eimeria minasensis n. sp. is described in the domestic goat Capra hircus from Brazil. Oocysts ellipsoidal are 35 x 24.5 (32-37.7 x 20.9-27.9) microns. Sporocysts elongate-ellipsoid are 15.2 x 9 (12.3-18.4 x 7.8-10.2) microns, with a Stieda body at the narrow end. Oocyst wall smooth and bilayered; outer layer about 1.2 (0.8-1.6) microns and colorless; inner layer about 0.5 (0.4-0.8) micron and dark-brown. Micropyle, a mound-shaped micropylar cap 1.6 x 8.9 (0.8-2 x 7-10.2) easily dislodged; one or more oocyst polar granules present. Oocyst residuum absent. Sporocyst residuum present, composed of many scattered granules. Sporozoites elongate, lying lengthwise, "head to tail" in the sporocysts; one or two refractile globules are usually visible. Sporulation time was 120 hr at 27 degrees C, prepatent period, 19 to 20 days and patent period 15 to 25 days. Gamonts, gametes and oocysts present in cecum and colon. Prevalence was 12.8% (6/47) in goats from Minas Gerais, Brazil.
Assuntos
Coccidiose/veterinária , Eimeria/isolamento & purificação , Doenças das Cabras/parasitologia , Animais , Brasil , Coccidiose/parasitologia , Eimeria/classificação , Eimeria/crescimento & desenvolvimento , CabrasRESUMO
The endogenous development and prepatent and patent periods of Eimeria ninakohlyakimovae were studied in 43 1-3-wk-old coccidia-free kids inoculated with 5.0 x 10(4), 1.5 x 10(5), 2.0 x 10(5), or 9.0 x 10(5) sporulated oocysts/kg. Twenty-five kids were killed at 24- or 48-hr intervals, 2-18 days after inoculation (DAI). Two generations of meronts, gamonts, gametes, and oocysts were found in sections stained with hematoxylin and eosin and examined using under light microscopy. The first generation of meronts developed in the endothelium of the lacteals, in the lamina propria, and in the lymphatic vessels of the ileum submucosa. Mature, first-generation meronts, 165.5 x 123.6 microm, were first found 10 DAI. Second-generation merogony developed in the crypt epithelial cells of the cecum and colon; mature meronts, 16.8 x 11.6 microm, were first seen 12 DAI. Gametogenesis occurred in the cecum and colon epithelium; mature microgamonts (16.1 x 13.0 microm), microgametes, macrogametes (14.7 x 12.5 microm), and oocysts (18.3 x 13.3 microm) were seen at 13 DAI. The course of the infection was followed in 18 kids examined every day until 24 DAI. The prepatent period was 14.7 (13-17) days and the patent period 6.8 (4-10) days. The sporulation time at 30 C, with constant aeration, was 2-3 days.