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1.
The prevalence of helminths recovered from 108 birds representing eight species of Ciconiiformes from the Brazilian west-central region are presented. The digeneans Ascocotyle (Phagicola) longa, Clinostomum marginatum, Cotylotretus grandis, Ithyoclinostomum dimorphum, the nematodes Contracaecum multipapillatum, Desmidocercella ardeae, Eustrongylides ignotus, and the cestode Valipora mutabilis were identified. Contracaecum multipapillatum was the most prevalent species and E. ignotus the most pathogenic. Gross lesions due to infections with C. multipapillatum were characterized by ulcerative processes and hyperemia of the mucosa whereas those caused by E. ignotus consisted of perforations of the gastric mucosa and fibrotic tubular lesions in the gastric serosa. Histopathological examinations revealed necrosis and mixed leucocyte infiltrations and discrete compression of the mucosa in C. multipapillatum infections. Destruction of the mucosa and submucosa with the presence of fibrous capsules were observed in E. ignotus infections. Reports of accidental human infections, with severe clinical signs induced by these parasites, indicate the necessity of a proper evaluation of the pathogenicity of helminths of aquatic birds.  相似文献   

2.
The effect of pollutants on the intensity of infection of metazoan parasites in the Mayan catfish, Ariopsis assimilis was investigated. Data were collected on pollutants and metazoan parasites from 76 catfish from five localities in Chetumal Bay in October, 1996. Nineteen pollutants (pesticides, polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs)) were found in the catfish livers. Heavy metal content was not determined. Nineteen metazoan parasite species were recovered. After controlling for fish length and sampling station, there was a significant negative linear relationship between the intensity of the larval digenean Mesostephanus appendiculatoides and 1,1,1,-trichloro-2,2-bis (4-chlorophenyl) ethane (DDT) concentrations. This negative relationship may be explained either by the effect of the pesticide on the mortality of (i) free-living larval forms, (ii) metacercariae in the fish, (iii) infected fish or (iv) intermediate host snails. There were significant differences between fish parasitized and not parasitized with M. appendiculatoides with respect to their DDT concentrations. There were also significant differences between the variances of the mean Clark's coefficient of condition values between catfish parasitized and not parasitized by M. appendiculatoides, with the variance of non-parasitized catfish being significantly larger. The results provided statistical evidence that DDT has a detrimental effect on M. appendiculatoides infection intensity. Furthermore, the significantly larger variance value of Clark's coefficient for non-parasitized fish suggested that DDT affects both the parasite and general host condition.  相似文献   

3.
Intestinal helminths and blood protozoa are common parasites of lizards. In captivity they can be a serious problem, but no information on treatments is available. In this study, several antiparasitic drugs were studied in Gallotia caesaris (Lacertida) from La Gomera, the Canary Islands, Spain. A lack of efficacy of chloroquine, and a decrease in haemogregarine (Apicomplexa) infection by atovaquone-proguanil was demonstrated. Furthermore, a positive effect of fenbendazole against intestinal nematode infection was observed. In the Canary Islands, Gallotia bravoana and Gallotia simonyi (Lacertida) are included in a captive breading recovery plan. The present results are useful in order to keep these animals in good condition and to control their parasites. Moreover, these results are important for reptiles kept as pets, due to the previous lack of knowledge of parasite management.  相似文献   

4.
The parasitic prevalence and mean intensity in the striped mullet, Mugil cephalus, was seasonally determined during an annual cycle (February 1994 to February 1995) in the confluence of the Colorado and Hardy rivers, Baja California, México. Two species of parasites were identified, a nematode, Contracaecum multipapillatum (von Drasche, 1882) (Ascaridida: Anisakidae), and a copepod, Ergasilus versicolor Wilson, 1911 (Poecilostomatoida: Ergasilidae). The larvae of C. multipapillatum, which were represented by two size classes (A and B stages), had prevalences of 30% and 14.5%, respectively; while A. versicolor had a prevalence of 72.7%. The mean intensity of C. multipapillatum was 6.18 and 2.37 individuals per infected fish for A and B stages, respectively; and for A. versicolor, it was of 4.01. The number of parasites (taxa combined) increased with the size of fish (r = 0.22, p = 0.02), but it was independent of the host's condition factor (KSL).  相似文献   

5.
Seventy raccoons (Procyon lotor) from western Kentucky were examined for helminths from December 1985 through May 1986. Twenty-three species of helminths were collected including 10 species of Trematoda (Brachylaima virginiana, Euryhelmis squamula, Eurytrema procyonis, Fibricola cratera, Gyrosoma singulare, Maritreminoides nettae, Mesostephanus appendiculatoides, Metagonimoides oregonensis, Paragonimus kellicotti, Pharyngostomoides procyonis), 2 species of Cestoda (Atriotaenia procyonis, Mesocestoides variabilis), 10 species of Nematoda (Arthrocephalus lotoris, Baylisascaris procyonis, Capillaria putorii, C. plica, Crenosoma goblei, Dracunculus insignis, Gnathostoma procyonis, Molineus barbatus, Physaloptera rara, Trichinella spiralis), and 1 species of Acanthocephala (Macracanthorhynchus ingens). A mean of 6.4 (3-11) helminth species per host was recorded. Fibricola cratera, Atriotaenia procyonis, Mesocestoides variabilis, Arthrocephalus lotoris, Capillaria plica, Dracunculus insignis, Molineus barbatus, and Physaloptera rara were ubiquitous parasites of the raccoon, whereas specific nidi were observed for Eurytrema procyonis, Gyrosoma singulare, Paragonimus kellicotti, Baylisascaris procyonis, Trichinella spiralis, and Macracanthorhyncus ingens. With an overall prevalence of 10% or higher, 15 of the 23 helminth species were considered common parasites of the raccoon in western Kentucky. When the 10% prevalence rate was applied within geographical quadrants to correct for the presence of nidi it was found that 18 of the 23 helminth species were common and 5 were regarded as rare parasites of the raccoon. Two species of nematodes, T. spiralis and B. procyonis, displayed a markedly higher prevalence in male raccoons.  相似文献   

6.
The subsocial spider mite Schizotetranychus longus lives gregariously in woven nests on leaves of Sasa bamboo. Adults of both sexes defend their young against the predatory mite Typhlodromus bambusae. The effects of web and female attendance of this species on offspring survival were evaluated in a natural forest. Experimental removal of web and females revealed that S. longus young suffered greater mortality than in the control. Furthermore, the web made by parent females had a positive effect on offspring survival, possibly through preventing predators from intruding into the nest. Attendance of a female in a nest also had an effect on improving the survival rate of her offspring over a short period. We could not detect any function of the web and female other than protection against predators at least for the 5 day period of the experiment. The nest web of S. longus has an important function in the survival of young by preventing the entry of pedestrian predators (generalist) and females may play a role in defending against specialized predators which can intrude into the nests.  相似文献   

7.
The interactions between parasitic helminths and gut microbiota are considered to be an important, although as yet incompletely understood, factor in the regulation of immunity, inflammation and a range of diseases. Infection with intestinal helminths is ubiquitous in grazing horses, with cyathostomins (about 50 species of which are recorded) predominating. Consequences of infection include both chronic effects, and an acute inflammatory syndrome, acute larval cyathostominosis, which sometimes follows removal of adult helminths by administration of anthelmintic drugs. The presence of cyathostomins as a resident helminth population of the equine gut (the “helminthome”) provides an opportunity to investigate the effect helminth infection, and its perturbation, has on both the immune system and bacterial microbiome of the gut, as well as to determine the specific mechanisms of pathophysiology involved in equine acute larval cyathostominosis. We studied changes in the faecal microbiota of two groups of horses following treatment with anthelmintics (fenbendazole or moxidectin). We found decreases in both alpha diversity and beta diversity of the faecal microbiota at Day 7 post-treatment, which were reversed by Day 14. These changes were accompanied by increases in inflammatory biomarkers. The general pattern of faecal microbiota detected was similar to that seen in the relatively few equine gut microbiome studies reported to date. We conclude that interplay between resident cyathostomin populations and the bacterial microbiota of the equine large intestine is important in maintaining homeostasis and that disturbance of this ecology can lead to gut dysbiosis and play a role in the aetiology of inflammatory conditions in the horse, including acute larval cyathostominosis.  相似文献   

8.
Cyathostomins are ubiquitous in grazing horses across the world, and anthelmintic resistance has been reported with increasing levels over past decades. The aims of the present study were (i) to investigate the efficacy against encysted larval stages of moxidectin (0.4?mg/kg) and fenbendazole (10?mg/kg daily for five consecutive days) and compare these regimens at 2 and 5?weeks post-treatment, (ii) to investigate individual cyathostomin species associated with shortened egg reappearance periods, and (iii) to document species exhibiting decreased susceptibility to the evaluated compounds. Thirty-six ponies were allocated to treatment groups with half euthanatized 2?weeks post-treatment, and the remainder necropsied after 5?weeks. Luminal and mucosal worm counts were conducted and strongyle egg counts were determined at weekly intervals. At 2?weeks, mean reductions of early L3s were 50.4% and 73.8% for fenbendazole and moxidectin, respectively. At 5?weeks, the respective efficacies were 51.3% and 71.8%. Two week efficacies against late L3s and L4s (LL3s/L4s) were 70.8% and 74.6% for fenbendazole and moxidectin, respectively, whereas very low numbers were found in all three groups at 5?weeks. None of the mucosal counts were significantly different between treatment groups. Fenbendazole and moxidectin reduced luminal worm counts by 93.2% and 98.3% at 2?weeks following administration, with moxidectin group adult counts being significantly lower than the other two groups (P?<?0.0001). Both treatment groups had increased counts 3?weeks later (P?=?0.0415). A moxidectin ERP of 4?weeks was associated with surviving luminal L4s, and adult species contributing to this were Cyathostomum catinatum, Cylicostephanus longibursatus, Cylicocyclus ashworthi and Cylicocyclus nassatus. This study documented (i) larvicidal efficacy of fenbendazole much lower than historical standards, (ii) survival of luminal immatures (L4) following moxidectin administration, and (iii) new information about cyathostomin species associated with these phenomena.  相似文献   

9.
10.
Gelatin-catechin conjugate was synthesized by the laccase-catalyzed oxidation of catechin in the presence of gelatin. The conjugate had a good scavenging activity against superoxide anion radicals. Moreover, the conjugate showed an amplified inhibition effect on human low density lipoprotein oxidation initiated by 2,2'-azobis(2-amidinopropane)dihydrochloride as a radical generator.  相似文献   

11.
Infections with gastrointestinal (GI) nematodes are amongst the most prevalent worldwide, especially in tropical climates. Control of these infections is primarily through treatment with anthelmintic drugs, but the rapid development of resistance to all the currently available classes of anthelmintic means that alternative treatments are urgently required. Cysteine proteinases from plants such as papaya, pineapple and fig are known to be substantially effective against three rodent GI nematodes, Heligmosomoides polygyrus, Trichuris muris and Protospirura muricola, both in vitro and in vivo. Here, based on in vitro motility assays and scanning electron microscopy, we extend these earlier reports, demonstrating the potency of this anthelmintic effect of plant cysteine proteinases against two GI helminths from different taxonomic groups - the canine hookworm, Ancylostoma ceylanicum, and the rodent cestode, Rodentolepis microstoma. In the case of hookworms, a mechanism of action targeting the surface layers of the cuticle indistinguishable from that reported earlier appears to be involved, and in the case of cestodes, the surface of the tegumental layers was also the principal location of damage. Hence, plant cysteine proteinases have a broad spectrum of activity against intestinal helminths (both nematodes and cestodes), a quality that reinforces their suitability for development as a much-needed novel treatment against GI helminths of humans and livestock.  相似文献   

12.
西氏贝蛔虫Baylisascaris schroederi是圈养大熊猫Ailuropoda melanoleuca最常见、危害最严重的一种体内寄生虫,采用药物驱虫是目前控制圈养大熊猫蛔虫病的主要措施。为了筛选有效的驱虫药物,本研究观察了3种苯并咪唑类药物(阿苯达唑片剂、芬苯达唑膏剂和甲苯咪唑片剂)对大熊猫蛔虫的驱虫效果,统计了驱虫前后粪检蛔虫卵转阴率及排虫情况。结果表明,除芬苯达唑按5 mg·kg^-1体质量口服,每天1次,连续服用2 d,效果较差外,3种药物按10 mg·kg^-1体质量口服,每天1次,连续服用2 d,用药安全且有较好的驱虫效果。  相似文献   

13.
Fifty-seven wild boars (Sus scrofa) from protected regions of Iran were examined for helminths. Sixteen species of helminths were collected; there were ten nematodes, one acanthocephalan, two trematodes and three larval cestodes. New host and distribution records were established for all helminths except of Taenia solium cysticerci. Wild boar shared nine of these helminths with domestic pigs, six with ruminants and three with human beings in Iran. Metastrongylus pudendotectus and M. salmi are reported for the first time from Iran.  相似文献   

14.
In the present study tactical fenbendazole treatments against ostertagiasis in calves were given at short intervals towards the end of the grazing season. This prevented clinical disease and had moderate effects on parasitic loads in animals that stayed on the same pasture throughout the season. The feasibility of tactical treatments is discussed in relation to various strategical control measures.  相似文献   

15.
Helminth-free bulls were injected artificially with Ostertagia ostertagi (120 000 L3), Cooperia oncophora (240000 L3), Haemonchus spec. (1 000 L3) and/or Dictyocaulus viviparus (60 L3/kg) orally or intraruminally. The animals were treated with fenbendazole during the prepatent period or after having reached maturity. The effect of 5 mg fenbendazole/kg p.o. on 3-d, 10-d- and adult stages of Ostertagia ostertagi, Haemonchus spec. and Cooperia oncophora ranges between less than 94% and 100%. Particularly noticeable was the effect on 10-d-old Ostertagia ostertagi with less than 94%. 5 mg/kg fenbendazole orally removed nearly 100% of 6-d-, 13-d-, and adult stages of Dictyocaulus viviparus. Fenbendazole may be administered as a drench or as medicated feed. The safety of the compound permits the administration of excessively high doses without clinical signs.  相似文献   

16.
The effect of ginseng sapogenins, aglycone parts of ginsenosides, against oxidative damage by radical generator, 2,2'-azobis (2-amidinopropane) dihydrochloride (AAPH), in renal epithelial LLC-PK(1) cells was investigated to identify the structural characteristics of sapogenins to have renoprotective effects. Of the tested sapogenins, Δ(20(21))-protopanaxatriol showed the strongest protective effect against the AAPH-induced LLC-PK(1) cell damage. Based on the structure and stronger activity of Δ(20(21))-protopanaxatriol than the other sapogenins, the hydroxyl group in C-6 and double bond in C-20(21) position were important for renoprotective effect of sapogenin against oxidative stress.  相似文献   

17.

Background

The single-dose benzimidazoles used against Trichuris trichiura infections in humans are not satisfactory. Likewise, the benzimidazole, fenbendazole, has varied efficacy against Trichuris suis whereas Oesophagostomum dentatum is highly sensitive to the drug. The reasons for low treatment efficacy of Trichuris spp. infections are not known.

Methodology

We studied the effect of fenbendazole, albendazole and levamisole on the motility of T. suis and O. dentatum and measured concentrations of the parent drug compounds and metabolites of the benzimidazoles within worms in vitro. The motility and concentrations of drug compounds within worms were compared between species and the maximum specific binding capacity (Bmax) of T. suis and O. dentatum towards the benzimidazoles was estimated. Comparisons of drug uptake in living and killed worms were made for both species.

Principal findings

The motility of T. suis was generally less decreased than the motility of O. dentatum when incubated in benzimidazoles, but was more decreased when incubated in levamisole. The Bmax were significantly lower for T. suis (106.6, and 612.7 pmol/mg dry worm tissue) than O. dentatum (395.2, 958.1 pmol/mg dry worm tissue) when incubated for 72 hours in fenbendazole and albendazole respectively. The total drug concentrations (pmol/mg dry worm tissue) were significantly lower within T. suis than O. dentatum whether killed or alive when incubated in all tested drugs (except in living worms exposed to fenbendazole). Relatively high proportions of the anthelmintic inactive metabolite fenbendazole sulphone was measured within T. suis (6–17.2%) as compared to O. dentatum (0.8–0.9%).

Conclusion/Significance

The general lower sensitivity of T. suis towards BZs in vitro seems to be related to a lower drug uptake. Furthermore, the relatively high occurrence of fenbendazole sulphone suggests a higher detoxifying capacity of T. suis as compared to O. dentatum.  相似文献   

18.
A high prevalence (86.7%) of various species of nematodes was observed in the stomach of great cormorants living in Lake Biwa, Japan. There were varying numbers of adults belonging to two common genera, Eustrongylides Jagerskiold 1909 (Nematoda: Dioctophymatidae) and Contracaecum Railliet & Henry 1912 (Nematoda: Anisakidae). The first included common adenophorean nematodes comprising a single species, Eustrongylides tubifex and the second comprised ascaroid nematodes that contained four named species: Contracaecum rudolphii Hartwich, 1964, Contracaecum microcephalum Yamaguti, 1961, Contracaecum multipapillatum Drasche, 1882 and Contracaecum chubutensis Garbin, 2008. After the prevalence and intensity of the infection had been noted, both types of nematodes were frequently observed to penetrate the mucosa and intrude into the wall of the glandular stomach, where they caused gross haemorrhage and ulceration. The Eustrongylides sp. was predominantly found in a nodular lesion of the proventricular wall, while Contracaecum spp. were observed either free in the lumen of the proventriculus or, on occasion, deeply penetrating its wall. Of the Contracaecum spp., C. rudolphii was the most prevalent. Grossly, large numbers of nematodes were present in infected stomachs (for C. rudolphii intensity was 1-34 and 3-57 nematodes in male birds and 1-21 and 1-32 in females; for C. microcephalum 1-2 and 1 in male birds and 1-2 in females; for C. multipapillatum 2 in male cormorants and no infection in females; for C. chubutensis 1-2 and 1 in male birds and 1-5 and 1 in females and for E. tubifex 1-5 nematodes in male birds and 2-8 in females). Ulcerative inflammation and hyperaemia were the most common pathological presentations, especially in areas that had been invaded by parasites. Microscopically, varying degrees of granulomatous inflammatory reactions were seen, in addition to degenerated nematodes which appeared to have deeply penetrated mucosal surfaces and were surrounded by fibrous connective tissues.  相似文献   

19.
福建省大田县山羊的寄生蠕虫种群和群落生态分析   总被引:1,自引:0,他引:1  
从30只山羊体内检得寄生蠕虫13种,其中吸虫6种、绦蚴1种、线虫6种.总感染率为100%,平均感染强度为646条.其中以鹿同盘吸虫的感染率、平均感染强度为最高.山羊感染蠕虫种类在1~8种之间.种群分布型均为聚集分布,优势种有8种.该寄生蠕虫群落中各种群感染率和密度与山羊性别和年龄无关.种间关联分析表明该寄生蠕虫群落中具亲和性的种对有7对,关联和负关联达显著水平以上的种对分别有2对和3对.  相似文献   

20.
盐酸洛拉曲克在体内、外对S-180细胞株的抗增殖作用   总被引:2,自引:0,他引:2  
研究合合成新型胸苷合成酶抑制剂盐酸洛拉曲克在体内、外对S-180细胞株及正常人胚肾HEK293细胞的抗增殖作用;使用MTT法测定抑制率,以提高荷腹水瘤小鼠存活时间及荷实体瘤瘤重减轻情况为指标考察盐酸洛拉曲克对S-180所致肿瘤的治疗作用。结果表明:在体外盐酸洛拉曲克对S-180肿瘤细胞株有较强的细胞毒作用,对正常细胞HEK293抑制作用较弱(P<0.05);体内实验显示盐酸洛拉曲克可明显提高荷腹水瘤小鼠的存活时间,减轻荷实体瘤小鼠的瘤重,疗效与氟尿嘧啶(10mg/kg)相当(P>0.05)或更好(P<0.05)。可见,盐酸洛拉曲克在体内、外对S-180肿瘤细胞有显著的抗增殖作用,在体外对肿瘤细胞 具有选择性的抗增殖作用。  相似文献   

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