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1.
The gross pathological and histopathological changes associated with parasitic infection in the European eel (Anguilla anguilla Linnaeus, 1758) was investigated. A total of 65 eels collected from three sampling localities in Eastern Delta, Egypt were examined over the period of January–May 2008. The fish were subjected to standard procedures for parasitological and pathological examinations. Overall, 22 (33.8%) of the 65 fish examined were found to have parasitic infections. The eels harbored a total of six parasite species; among them, the nematode Anguillicoloides crassus was the most prevalent species (10.7%), followed by the Monogenea Pseudodactylogyrus anguillae (7.7%) and Dactylogyrus species (6.1%), the ciliate Trichodinella epizootica (4.6%), the Myxozoa Myxidium giardi (3.1%), and the cestode Proteocephalus macrocephalus (1.5%). Affected fish showed varying levels of tissue damage and pathological alterations including mild to severe degenerative, necrotic, and inflammatory changes in the affected organs.  相似文献   

2.
A new species of parasitic nematode, Procamallanus (Spirocamallanus) anguillae sp. n. (family Camallanidae), is described based on specimens recovered from the intestine of the Indonesian eel Anguilla bicolor McClelland (type host) from southern Thailand (type locality Phuket Island). It is characterized mainly by the presence of 10–13 spiral ridges in the buccal capsule, length of spicules (366–372 μm and 198–216 μm), presence of a gubernaculum, arrangement of caudal papillae, and by the broad female tail with a digit-like projection bearing two cuticular spikes. In addition, two species of larval nematodes, Physalopteridae gen. sp. and Anisakis cf. simplex (Rudolphi 1809), were recorded from A. bicolor. All species are briefly described and illustrated.  相似文献   

3.
The objective of the present study was to determine the prevalence and associated determinants (e.g., sex, age, on-farm management and husbandry) of gastrointestinal (GI) helminths in the domestic animals of district Toba Tek Singh, Punjab, Pakistan. For this purpose, 1,140 cattle, 1,140 buffaloes, 660 goats, 840 sheep, and 156 camels were randomly selected and their fecal samples were screened every other week for a year using a modified floatation technique. The samples positive for strongyle-type eggs had the parasite species identified using coproculture. It was found that the prevalence of GI helminths was significantly higher (P < 0.05) in sheep (44.17%; 371/840) than in other livestock. Sheep were followed in order by goats (40.15%; 265/660), buffaloes (39.82%; 454/1,140), and cattle (33.68%; 384/1,140). The important helminth species identified were Fasciola (F.) gigantica, Fasciola hepatica, Haemonchus contortus, Toxocara vitulorum, Trichostrongylus spp., Oesophagostomum spp., Ostertagia spp., Cooperia spp., Strongyloides spp., Moniezia spp., and Trichuris spp. The prevalence of GI helminths except F. hepatica and F. gigantica was significantly higher in grazing animals, females (P < 0.05) and young (P < 0.05) of all the host species when compared with stall-fed animals, males and adults, respectively. Using ponds and rivers/canals as drinking water were found to have significant influence (P < 0.05) on the prevalence of GI helminths. The results provide a baseline data for planning future research and control strategies against GI helminthes.  相似文献   

4.
It is widely assumed that the likelihood of invasion decreases with increased species richness in the recipient community. However, the invasion paradox supports a negative and a positive relationship between native biodiversity and the success of an invader. Here, we show that for a host–parasite system (Anguilla anguilla as host and Anguillicoloides crassus as parasitic invader), invasion increases with native micro- and macroparasitic species richness. In fact, about 30% of the A. crassus intensity in eels could be explained by the number of both micro- and macroparasite species. This pattern could be due to the fact that A. crassus exploits a niche (the swim bladder) that is unoccupied by native parasite species and by the Th1/Th2 trade-off between native microparasites and the invader. We conclude that the host–parasite system resistance to invasion may depend on both niche availability and the Th1/Th2 trade-off. As well, we encourage researchers to incorporate native parasite richness as a risk factor in epidemiological models of A. crassus.  相似文献   

5.
An experiment was conducted to test the effect of the infection by the swimbladder nematode Anguillicola crassus on the survival of the European eel Anguilla anguilla when exposed to hypoxic conditions. Forty-four wild caught and naturally infected eels were placed in an aquarium filled with water from the fishing site (Vaccarès Lagoon, French Mediterranean coast). In this confined environment (271), under decreasing oxygen resources, the first eel death occurred after 45 h (O2 = 0.98 mg l−1) and the last one after 96 h (O2 = 0.48 mg l−1). After dissection and parasite examination, analyses revealed significant negative correlations between the time to death and various parameters of parasite pressure (e.g., number of lumen worms, parasite mass, health state of the infected organ). It was shown that the severity of damage to the swimbladder rather than the count of living parasites was the major contributing factor in explaining the variation in time to death. These semi-experimental data demonstrating an increased eel mortality rate under severe oxygen stress are discussed for their relevance under field conditions, especially during hot summer months.  相似文献   

6.
The aim of this study was to report the prevalence of intestinal parasites in stool specimens from outpatients in Catalonia (Spain), and to evaluate the association of age, seasonality, and gender on general parasitisation and by the most frequent detected species. A total of 13,913 samples from 8,313 patients (1–3 specimens per patient) reporting digestive disorders were examined between 1999 and 2005 as a part of medical examinations. Samples were fixed with MIF solution and microscopically examined as wet mounts. Permanent stain was obtained by the modified Ziehl–Neelsen technique for intestinal coccidia. Nineteen species of intestinal parasites were identified. Blastocystis hominis (585 patients) was the predominant species, followed by Giardia duodenalis (321), Dientamoeba fragilis (131), Entamoeba coli (60) and Cryptosporidium sp. (59). Prevalence of helminths was low, being Enterobius vermicularis as the most frequently reported helminth (49 patients). The overall parasitisation was 1,136/8,313 (13.7%); prevalence in adults was 19.8% with a maximum in spring (14.8%). In the adjusted models, age was the main factor associated with infection: adults, with B. hominis and Entamoeba coli (odds ratio (OR) = 6.0 and OR = 8.5, respectively) and children, with Cryptosporidium and Giardia (OR = 2.0 and OR = 3.3, respectively). However, seasonality cannot be considered related with infection. The total prevalence was low, taking into account that all the subjects examined presented gastrointestinal symptoms and that species traditionally considered as non-pathogenic were included in the study.  相似文献   

7.
For decades, drug resistance has been the major obstacle in the fight against malaria, and the search for new drugs together with the combination therapy constitutes the major approach in responding to this situation. The present study aims at assessing the in vitro antimalarial activity of four compounds isolated from Kigelia africana stem bark (atranorin - KAE1, specicoside - KAE7, 2β,3β,19α-trihydroxy-urs-12-20-en-28-oic acid – KAE3, and p-hydroxy-cinnamic acid – KAE10) and their drug interactions among themselves and their combination effects with quinine and artemether. The antiplasmodial activity and drug interactions were evaluated against the multidrug-resistant W2mef strain of Plasmodium falciparum using the parasite lactate dehydrogenase assay. Three of the four compounds tested were significantly active against W2mef: specicoside (IC50 = 1.02 ± 0.17 μM), 2β,3β,19α-trihydroxy-urs-12-en-28-oic acid (IC50 = 1.86 ± 0.15 μM) and atranorin (IC50 = 1.78 ± 0.18 μM), whereas p-hydroxy-cinnamic acid showed a weak activity (IC50 = 12.89 ± 0.87 μM). A slight synergistic effect was observed between atranorin and 2β,3β,19α-trihydroxy-urs-12-en-28-oic acid (Combination index, CI = 0.82) whereas the interaction between specicoside and p-hydroxy-cinnamic acid were instead antagonistic (CI = 2.67). All the three compounds showed synergistic effects with artemether, unlike the slight antagonistic interactions of atranorin and 2β,3β,19α-trihydroxy-urs-12-en-28-oic acid in combination with quinine. K. africana compounds are therefore likely to serve as leads in the development of new partner drugs in artemether-based combination therapy.  相似文献   

8.
A lack of newly acquired species partly explains why introduced host species have poor specific parasite diversity. The intestinal helminth community from two native Murid host species, wood mice Apodemus sylvaticus [Murinae] (n = 40), bank voles Clethrionomys glareolus [Arvicolinae] (n = 42), and an introduced Sciurid, the Siberian chipmunk Tamias sibiricus (n = 42), dominant in the rodent communities, was studied from three woody areas in the Ile-de-France region. Native gastrointestinal helminth fauna from mice and voles was formed by 12 taxa: ten nematodes, Aonchotheca murissylvatici, Aonchotheca annulosa, Aspiculuris tetraptera, Eucoleus sp., Heligmosomoides glareoli, Heligmosomoides polygyrus, Mastophorus muris, Syphacia frederici, Syphacia stroma, Trichuris muris, a Cestode and a Trematode. Two helminth taxa were imported by chipmunks from eastern Asia: Brevistriata skrjabini and Strongyloides callosciureus. Only A. annulosa was transferred to chipmunks from the native small rodent community. None of the 82 native murids harbored chipmunk helminths. The developmental ability of helminth according to host phylogenetic relatedness was the main driving force explaining the species composition of the helminth community between these sympatric native and introduced hosts.  相似文献   

9.
From 2004 to 2009, the digestive tracts of 111 dogs from suburban areas around Tirana, Albania, were examined for intestinal helminths. In addition, rectal faecal samples of all dogs were examined for protozoan infections and 48 faecal samples from dogs >6 months of age were processed with the Baermann technique to test for the excretion of lungworm larvae. The heart and pulmonary arteries of 30 dogs >6 months of age also were examined for nematode parasites. The intestinal parasite fauna of the dogs included three protozoan species (Cystoisospora canis, Cystoisospora ohioensis/burrowsi, Sarcocystis spp.), three cestode species (Dipylidium caninum, Taenia hydatigena, Echinococcus granulosus), five nematode species (Ancylostoma caninum, Uncinaria stenocephala, Toxocara canis, Toxascaris leonina, Trichuris vulpis) and one acanthocephalan (Centrorhynchus buteonis). Rates of infection were: 15.3% for C. canis, 31.5% for C. ohioensis/burrowsi, 1.8% for Sarcocystis spp., 65.8% for D. caninum, 16.2% for T. hydatigena, 2.7% for E. granulosus (genotype G1), 13.5% for A. caninum, 64.9% for U. stenocephala, 75.7% for T. canis, 0.9% for T. leonina, 21.6% for T. vulpis and 0.9% for C. buteonis. Up to six species of gastrointestinal parasites were found per dog. The 63 ≤6-month-old dogs harboured significantly (p < 0.001) fewer gastrointestinal parasite species concurrently (mean 2.65 ± 1.25 species per animal) than the 48 older animals (mean 3.77 ± 1.45 species per animal). Dogs >6 months of age harboured significantly (p < 0.05) more D. caninum, T. hydatigena, A. caninum, U. stenocephala and T. vulpis compared to younger dogs. Conversely, the younger dogs harboured significantly (p < 0.001) more T. canis than the older ones. There was no difference in the male and female dogs’ counts of individual intestinal helminth species apart from T. hydatigena in dogs >6 months of age: Male dogs harboured significantly (p < 0.05) more tapeworms than female dogs. Based on faecal examination, there was no indication for lungworm infection; however, two adult heartworms (Dirofilaria immitis) were found in the right ventricle of one dog.  相似文献   

10.
The limited availability of water results in the reuse of wastewater or sludge. The Tunisian wastewater regulatory guidelines have specific limits for ova of helminths (<1 egg/l) but none for protozoan parasites. We assessed the presence and loads of parasites in 20 samples of raw, treated wastewater and sludge collected from six wastewater treatment plants. Samples were tested by microscopy using the modified Bailenger method (MBM), immunomagnetic separation (IMS) followed by immunofluorescent assay microscopy, and PCR and sequence analysis for the protozoa Cryptosporidium and Giardia. The seven samples of raw wastewater had a high diversity of helminth and protozoa contamination. Giardia spp., Entamoeba histolytica/dispar, Entamoeba coli, Ascaris spp., Enterobius vermicularis, and Taenia saginata were detected by MBM, and protozoan loads were greater than helminth loads. Cryptosporidium and Giardia were also detected by IMS microscopy and PCR. Six of the eight samples of treated wastewater had parasites: helminths (n = 1), Cryptosporidium (n = 1), Giardia (n = 4), and Entamoeba (n = 4). Four of five samples of sludge had microscopically detectable parasites, and all had both Cryptosporidium and Giardia. The genotypes and subtypes of Cryptosporidium and Giardia were of both human and animal origin. These findings suggest that it may be important to monitor the presence of protozoan parasites in treated wastewater and sludge in Tunisia.  相似文献   

11.
In order to assess the potential of the stem bark of Kigelia africana (Lam.) Benth as source of new anti-malarial leads, n-hexane and ethyl acetate (EtOAc) extracts and four compounds isolated from the stem bark were screened in vitro against the chloroquine-resistant W-2 and two field isolates of Plasmodium falciparum using lactate dehydrogenase assay. The products were also tested for their cytotoxicity on LLC/MK2 monkey kidney cells. The EtOAc extract exhibited a significant antiplasmodial activity (IC50 = 11.15 μg/mL on W-2; 3.91 and 4.74 μg/mL on field CAM10 and SHF4 isolates, respectively), whereas the n-hexane fraction showed a weak activity (IC50 = 73.78 μg/mL on W-2 and 21.85 μg/mL on SHF4). Three out of the four compounds showed good activity against all the three different parasite strains (IC50 < 5 μM). Specicoside exhibited the highest activity on W-2 (IC50 = 1.54 μM) followed by 2β, 3β, 19α-trihydroxy-urs-12-en-28-oic acid (IC50 = 1.60 μM) and atranorin (IC50 = 4.41 μM), while p-hydroxycinnamic acid was the least active (IC50 = 53.84 μM). The EtOAc extract and its isolated compounds (specicoside and p-hydroxycinnamic acid) were non-cytotoxic (CC50 > 30 μg/mL), whereas the n-hexane extract and two of its products, atranorin and 2β, 3β, 19α-trihydroxy-urs-12-en-28-oic acid showed cytotoxicity at high concentrations, with the last one being the most toxic (CC50 = 9.37 μg/mL). These findings justify the use of K. africana stem bark as antimalaria by traditional healers of Western Cameroon, and could constitute a good basis for further studies towards development of new leads or natural drugs for malaria.  相似文献   

12.
An extensive survey of helminth parasites in 1,316 freshwater fish representing 31 species from two aquatic ecosystems in southeastern Slovakia characterized by different level of environmental pollution was carried out. The helminth species diversity was compared between the Tisa River, heavily polluted with cyanides and heavy metals after a series of ecological disasters in 2000, and the less anthropogenically influenced Latorica River. A parasitological survey found 31 gastrointestinal helminths: Trematoda (11 species), Cestoda (14), Acanthocephala (3) and Nematoda (3). As many as 70 host−parasite combinations have been found. Twenty of them (28.6%) represent new host−parasite finding records for the territory of Slovakia. The component communities were species-poor in both rivers, with high dominance of one to three helminth species. Even though the fish communities were qualitatively similar (ICS = 81%) and the number of fish examined was approximately the same (676 and 640) in both localities, the helminth species richness and diversity of host−parasite combinations were two times lower in the more polluted Tisa River. The helminth communities were also much less abundant in the Tisa River. Based on the Czekanowski−S?rensen similarity index (ICS = 48.8%) and the Percentage similarity index (PI = 19.5%), the helminth communities were qualitatively and quantitatively different in the two rivers. The remarkable lack of species diversity in the Tisa River can be explained by the negative impact of residual contamination of the Tisa river bottom on certain freshwater invertebrates (bivalves and prosobranch mollusks, copepods and amphipods) which serve as obligatory intermediate hosts for the helminths. Four species, the aspidogastrean Aspidogaster limacoides Diesing, 1835, the acanthocephalan Pomphorhynchus tereticollis (Rudolphi, 1809) tapeworms Atractolytocestus huronensis Anthony, 1958 and Khawia sinensis Hsü, 1935 are recorded in Slovakia for the first time. This study was supported by the Grant Agency VEGA (project No. 2/7192/27), Slovak Research and Development Agency (project Nos. APVV-51-062205 and LPP-0151-07), the Institute of Parasitology (project Nos. Z60220518 and LC 522) and Grant Agency of the Czech Republic (project No. 524/08/0885).  相似文献   

13.
Two types of lactose-specific lectins, galectin (AJL-1) and C-type lectin (AJL-2), were previously identified in the mucus of adult Anguilla japonica. Here, we compared the expression profiles of these two homologous lectins at the adult and juvenile stages between the tropical eel Anguilla marmorata and the temperate eel A. japonica. Only one lectin, predicted to be an orthologue of AJL-1 by LC-MS/MS, was detected in the mucus of adult A. marmorata. We also found that an orthologous gene to AJL-2 was expressed at very low levels, or not at all, in the skin of adult A. marmorata. However, we detected the gene expression of an AJL-2-orthologue in the skin of juvenile A. marmorata, and a specific antibody also detected the lectin in the juvenile fish epidermis. These findings suggest that expression profiles of mucosal lectins vary during development as well as between species in the Anguilla genus.  相似文献   

14.
In the present study, two abundant sympatric rodent species (27 Apodemus flavicollis and 33 A. sylvaticus) were studied for their endo- and ectoparasite fauna. The rodents were trapped in Dormagen, a city in North Rhine–Westphalia, Germany. A total of 20 different parasites species were identified, 13 endoparasite (2 Digenea, 5 Cestoda and 7 Nematoda) and 7 ectoparasite (5 Insecta and 2 Arachnida) species. Thirteen parasite species were found inhabiting both rodent species. The predominant endoparasite species in both rodents was the nematode Pelodera strongyloides, followed by the nematode Heligmosomoides polygyrus and a Syphacia species. The flea Ctenophthalmus agyrtes was the dominant ectoparasite in both rodent species. A. flavicollis usually carried 1–7 ecto-/endoparasite species (mean 4.0), whereas A. sylvaticus were mostly infested with 1–9 (mean 4.4). The parasite diversity of A. flavicollis (H′ = 0.268, J = 0.097) was marginal lower in comparison to A. sylvaticus (H′ = 0.319, J = 0.110). The two rodent species examined show remarkable similarities in the composition of their endo- and ectoparasite fauna being directly related to their similar pattern of living in the investigated area.  相似文献   

15.
The aim of this study was to investigate the clinical significance of nontuberculous mycobacteria (NTM) isolates in elderly Taiwanese patients. From 2004 through 2008, patients >65 years old with NTM isolation were identified. The definitions of NTM disease followed the American Thoracic Society and Infectious Disease Society of America (ATS/IDSA) criteria. Among the 3,175 NTM isolates, Mycobacterium avium complex (MAC; n = 1,118, 35.2%) was the most prevalent species, followed by M. abscessus (n = 545, 17.2%). Among the 1,633 elderly patients with NTM isolates, the most prevalent NTM species were MAC (n = 592, 36.3%) and M. fortuitum complex (n = 311, 19.0%). NTM colonization was found in 1,339 (80.4%) patients and only 326 (19.6%) patients had NTM diseases. During the study period, the annual incidence rates (per 100,000 inpatients and outpatients) of NTM colonization and disease both increased significantly (p < 0.0001) from 10.5 to 15.8 and from 2.1 to 4.3, respectively. Isolated pulmonary NTM infections compromised 294 (90.2%) of the 326 elderly cases of NTM disease. In conclusion, this study found an increasing trend in the incidence of both NTM isolates and NTM diseases among elderly Taiwanese patients. MAC and M. abscessus were the most frequent species causing various types of NTM disease.  相似文献   

16.
The migratory response of peripheral blood granulocytes and monocytes from the European eel Anguilla anguilla (L.) to infective larvae of the swimbladder nematode Anguillicola crassus Kuwahara, Niimi and Hagaki, 1974 was examined by means of light microscopical histology and with an in vitro assay using a modified Boyden chamber. Histological examination of experimentally infected eels revealed that, already 8 days postinfection, an infiltration of inflammatory cells around L3 of A. crassus in the swimbladder tissue can occur. In the Boyden chamber, in presence of infective larvae of A. crassus (L3), neutrophil granulocytes and monocytes showed a higher migration activity than in the absence of L3. In conclusion, infection of European eels with A. crassus leads to an activation of the defence cells resulting in an increased migration activity compared to uninfected eels.  相似文献   

17.
In the present study, scanning electron microscopy is used to demonstrate the surface features of Pseudodactylogyrus anguillae Yin and Sproston (1948) Gussev, 1965 and Pseudodactylogyrus bini Kikuchi (1929) Gussev, 1965 from the European eel Anguilla anguilla. Specimens of the eel A. anguilla were collected from the River Nile, near Mansoura, Dakahlia Province, Egypt. Morphologically, P. anguillae could be distinguished from P. bini based on the total length, the shape and size of the haptor, and the constriction between the haptor and body proper. The general body tegument and the haptoral tegument of both species are microvillous. Possible functions of the microvilli associated with the tegument covering the anterior adhesive areas are discussed. The region of the body proper just anterior to the haptor of P. anguillae, appears to be highly folded and provided with many projections forming scale-like structures. Many surface ciliary sensilla presumed to be sensory structures are found on the tegument of the anterior adhesive area of P. anguillae. Secretory bodies and mucus-like substances are recorded on the tegument covering the anterior adhesive areas of P. anguillae and the haptor of P. bini. The possible role of these secretions in the attachment of the anterior adhesive areas and the posterior attachment haptor to the host tissues are also discussed.  相似文献   

18.
The aim of this study was to compare the microbial composition of the subgingival biofilm from teeth and implant sulci in relation to contents originating from internal parts of the implant, abutment and implant prosthesis. Twenty subgingival biofilm samples from the mesial and distal aspects of each tooth/implant and 29 samples from the internal parts of titanium implants, abutments and implant prostheses were evaluated for the presence of 18 bacterial species using DNA Checkerboard and the differences between samples from teeth and implants were assessed with Pearson’s correlation analysis. The periodontal and peri-implantar sulci presented significantly higher bacterial counts than the implant-related sites (p < 0.05 and p < 0.01, respectively). The highest counts were observed for Capnocytophaga gingivalis, Prevotella intermedia, P. nigrescens and P. micra. The correlation between the counts in the periodontal and peri-implantar sulci was r = 0.66 (p < 0.001). Weaker correlations between samples from the internal parts of the implants and periodontal sulcus (r = 0.49; p < 0.001) or peri-implant sulcus (r = 0.42; p < 0.001) were found. All 18 bacterial species were detected to be colonising the subgingival sulcus of teeth and implants, and implant components in the evaluated patients. Significant correlations between the microbiota were found, the strongest being between the periodontal and peri-implantar sulci.  相似文献   

19.
Serum samples from sand gazelles (n = 227), mountain gazelles (n = 232), and Arabian oryx (n = 96) reared in captivity in Riyadh, Saudi Arabia were tested for the presence of Coxiella burnetii antibodies using an indirect enzyme immunoassay. C. burnetii antibodies were present in 18.3%, 7.3%, and 46.9% of these animals, respectively. The difference in serological prevalence between the three species was statistically significant. Age- and sex-related differences in prevalence were also observed. This study is the first record of C. burnetii antibodies in Arabian gazelles.  相似文献   

20.
Probable arthropod vectors of avian blood protozoa, Leucocytozoon lovati, were collected in the alpine regions of Japan, the habitats of the host birds of Japanese rock ptarmigan (Lagopus mutus japonicus). Seven alpine regions of Japan, Asahidake, Chogatake, Tateyama, Jiigatake, Norikura, Kitadake, and Senjyogatake were investigated for black fly collection during 2004 to 2007. The collected 490 insects were morphologically identified as six species of female black flies, including Prosimulium hirtipes group (n = 59), Prosimulium mutata (n = 13), Prosimulium yezoense (n = 10), Similium japonicum (n = 359), Similium uchidai (n = 39), and Twinnia japonensis (n = 10). Extracted DNAs from individual black fly species were utilized for the amplification of the partial mitochondrial cytochrome b gene sequences of Leucocytozoon lovati previously reported. Four S. japonicum, two S. uchidai, and two P. hirtipes group studied were positive for the nested PCR among 490 black flies collected (1.6%; 8/490). All amplified sequences from the black flies were completely identical to those of L. lovati previously detected from Japanese rock ptarmigan. Our results suggest that at least three species of black flies, S. japonicum, S. uchidai, and P. hirtipes group, studied in this area could be regarded as potential vectors for L. lovati in the rock ptarmigan. This is the first detection case of Leucocytozoon from black flies of Japan.  相似文献   

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