共查询到19条相似文献，搜索用时 265 毫秒
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用大片形吸虫和肝片形吸虫感染家兔以便选择大片形吸虫对动物的最佳感染量，及明确号肝片形吸虫和大片形吸虫的生物学和对动物宿主的致病力的差别。结果显示肝片形吸虫虫体在兔体内发育成熟的时间早于大片形吸虫．感染成活率更高，对动物的病理损害明显比感染大片形吸虫兔的病变要轻。本试验证实这两种片形吸虫除了形态学的差异外，在对动物致病力、病理损害等万面确实存在差别。 相似文献
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腹腔吸虫寄生在反刍类的胆管和胆囊内而引起发病，对绵羊可造成死亡。它的中间宿主是螺、蜗牛和蚂蚁，羊吃了体内含囊蚴的蚂蚁而引起感染。 相似文献
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水牛实验感染大片吸虫及ELISA检测特异性抗体的变化 总被引：3，自引：0，他引：3
目的 本试验为了对水牛感染大片吸虫的情况进行了解。方法 选 10头 6月龄水牛 ,分成 2组 ,每组 5头 ,A组对照 ,B组试验 ,每头经口感染 2 5 0个大片吸虫囊蚴。结果 水牛感染大片吸虫后的收虫率为 16 .2± 8.0 % ,在感染后第 13～ 14周检出虫卵。抗大片吸虫分泌排泄产物 Ig G水平从感染后第 2周明显升高 ,17周时达到高峰。结论 试验证实水牛对大片吸虫感染很敏感 ,EL ISA检测特异性抗体用于片形吸虫病的早期诊断有一定的意义 相似文献
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Raadsma HW Kingsford NM Suharyanta Spithill TW Piedrafita D 《Veterinary parasitology》2007,143(3-4):275-286
This study reports the early biochemical changes in plasma, comparative host-immune responses and parasite recovery data in Merino sheep during the first 10 weeks of infection with Fasciola gigantica and Fasciola hepatica. One group of sheep were uninfected, four groups of sheep received incremental challenge doses of F. gigantica metacercariae (50, 125, 225 and 400, respectively) and the sixth group was challenged with 250 F. hepatica metacercariae. At 10 weeks post infection (wpi), sheep challenged with F. hepatica showed the greatest fluke recovery (mean 119, range 84-166); a significantly higher biomass of parasites recovered (2.5-fold greater than the highest dose of F. gigantica); and a greater mean % parasite recovery (39.3%, range 27-55%) than any group challenged with F. gigantica. Within the groups dosed with F. gigantica a strong dose-dependent response was observed in both fluke recovery and fluke biomass with increasing dose of metacercariae. The mean % parasite recovery of F. gigantica infected groups 1-5 were 26, 23, 26 and 25%, respectively, suggesting a uniform viability of parasite establishment independent of infection dose. At 6 wpi, elevated levels of plasma GLDH were observed in the F. gigantica infected groups compared to the uninfected sheep (p<0.005) whereas the F. hepatica challenged group had four-fold higher levels of GLDH compared to the F. gigantica infected group (p<0.001). Elevated levels of GGT as an indicator of epithelial damage in the bile duct was only seen in the group challenged with F. hepatica at 10 wpi when it rose from below 100 IU/l to approximately 250 IU/l (p<0.0001) whereas no detectable increase in GGT was observed in any of the groups challenged with F. gigantica. The white blood cell response to F. hepatica infection was biphasic with the initial peak at 4 wpi and a second peak at 9 wpi, corresponding to the period of migration of juvenile fluke in the liver and the time when adult flukes are migrating into the bile duct, respectively. This biphasic response was also evident in the changes in the eosinophil counts and serum haemoglobin levels. There was a trend toward higher parasite-specific IgG2 titres in sheep infected with lower worm burdens, suggesting that higher F. gigantica or F. hepatica burdens suppress IgG2 responses. The findings of this study suggest that, in early infection in a permissive host, F. hepatica appears to be more pathogenic than F. gigantica because of its rapid increase in size and the speed of its progression through the migratory phases of its life cycle. 相似文献
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Experimental infections of Lymnaea truncatula with a digenean species (Fasciola gigantica, F. hepatica, or Paramphistomum daubneyi) were performed under laboratory conditions to study the effect of four sources of food (microalgae, romaine lettuce, wheat germs, or modified Boray diet) on cercarial production. The mean number of F. hepatica, F. gigantica, or P. daubneyi cercariae was significantly greater when snail food was microalgae or Boray diet. The lowest cost prices for 100 metacercariae of F. hepatica (9.7-10.1 euros) were noted when algae of Boray diet were used as food for snails. In contrast, the highest prices (18.0-18.5 euros) were found in lettuce-reared snails. The choice of a source of food for breeding the intermediate hosts of F. hepatica and collecting metacercariae must take into account the importance of the commercial demand for metacercariae and will depend on the strategy the producer wishes to develop. 相似文献
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R M Alves L J van Rensburg J A van Wyk 《The Onderstepoort journal of veterinary research》1988,55(3):157-163
The faeces of 11 horses were examined for Fasciola spp. eggs. One of them was positive for Fasciola hepatica, a finding which was confirmed post-mortem. The 10 negative horses were subsequently infested with either F. hepatica or Fasciola gigantica, each animal receiving orally from 500-9,500 metacercariae. No clinical signs were observed and no fluke eggs were detected in the faeces, and neither immature nor adult Fasciola worms were recovered from the horses slaughtered 16-26 weeks post-infestation with F. hepatica and 28-34 weeks post-infestation with F. gigantica, respectively. The results indicate that horses have a high level of resistance to both South African Fasciola spp. Factors which can probably explain the conflicting reports for the prevalences of fascioliasis in horses throughout the world and the varying results obtained in experimental infestations are briefly considered. 相似文献
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目的明确重庆地区片形吸虫的种类,并为重庆地区片形吸虫的分类研究提供科学的参考依据。方法在对重庆地区黄牛、水牛肝脏上寄生的片形吸虫形态结构进行观察后,根据片形吸虫第一内转录间隔区(ITS-1)和第二内转录间隔区(ITS-2)基因设计特异性引物,运用多聚酶链式反应(PCR)技术,以法国肝片吸虫gDNA为对照,对所采样品gDNA用大片吸虫和肝片吸虫的ITS-1和ITS-2特异性引物进行扩增。结果形态学鉴定均为“不规则”片形吸虫,电泳结果显示均分别扩增出特异性ITS-1和ITS-2条带。结论综合形态学和PCR鉴定结果,初步认为重庆地区存在着大片吸虫和肝片吸虫的“中间型”。 相似文献
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A previous study conducted in Belgium revealed that genetic material of Fasciola sp. was present in snail species belonging to the genus Radix. Here, these snails were collected and identified by DNA-based techniques as Radix labiata and Radix balthica. These two species and Galba truncatula (the major intermediate host in Europe) were experimentally infected with Fasciola hepatica. The resulting metacercariae were fed to rats and the infection was monitored using several techniques. Microscopy revealed the presence of larval stages in 78.3, 45, and 6.25% of G. truncatula, R. labiata, and R. balthica snails, respectively. These results were confirmed by a PCR that amplifies a Fasciola sp. specific sequence. Furthermore, this PCR was found to be more sensitive than microscopic examination. R. labiata shed fewer metacercariae than G. truncatula but these were as infective to rats as those shed by G. truncatula. This study demonstrates that R. labiata may act as an incidental intermediate host for F. hepatica in Belgium. 相似文献
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Pleasance J Raadsma HW Estuningsih SE Widjajanti S Meeusen E Piedrafita D 《Veterinary parasitology》2011,178(3-4):264-272
In the current study, three independent trials directly compared Fasciola gigantica and Fasciola hepatica infection of ITT sheep. In all trials, F. hepatica infection resulted in higher worm burden recoveries and greater physiological damage to ITT sheep. Developmental differences of the two Fasciola species were also observed during the first twelve weeks of a primary infection, where the migration and growth of F. hepatica was more rapid than F. gigantica. Various immunological blood parameters were measured and indicated similar kinetics in the humoral and cellular responses during the time course of infection with each Fasciola species. In contrast to F. hepatica infection, we demonstrate an innate and adaptive comparative ability of ITT sheep to resist the early stages of infection with F. gigantica infection. Unraveling the mechanisms leading to this differential resistance may potentially lead to new methods for the control of fasciolosis and other human liver flukes. 相似文献
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Ai L Weng YB Elsheikha HM Zhao GH Alasaad S Chen JX Li J Li HL Wang CR Chen MX Lin RQ Zhu XQ 《Veterinary parasitology》2011,181(2-4):329-334
The present study examined sequence variability in a portion of the mitochondrial cytochrome c oxidase subunit 1 (pcox1) and NADH dehydrogenase subunits 4 and 5 (pnad4 and pnad5) among 39 isolates of Fasciola spp., from different hosts from China, Niger, France, the United States of America, and Spain; and their phylogenetic relationships were re-constructed. Intra-species sequence variations were 0.0-1.1% for pcox1, 0.0-2.7% for pnad4, and 0.0-3.3% for pnad5 for Fasciola hepatica; 0.0-1.8% for pcox1, 0.0-2.5% for pnad4, and 0.0-4.2% for pnad5 for Fasciola gigantica, and 0.0-0.9% for pcox1, 0.0-0.2% for pnad4, and 0.0-1.1% for pnad5 for the intermediate Fasciola form. Whereas, nucleotide differences were 2.1-2.7% for pcox1, 3.1-3.3% for pnad4, and 4.2-4.8% for pnad5 between F. hepatica and F. gigantica; were 1.3-1.5% for pcox1, 2.1-2.9% for pnad4, 3.1-3.4% for pnad5 between F. hepatica and the intermediate form; and were 0.9-1.1% for pcox1, 1.4-1.8% for pnad4, 2.2-2.4% for pnad5 between F. gigantica and the intermediate form. Phylogenetic analysis based on the combined sequences of pcox1, pnad4 and pnad5 revealed distinct groupings of isolates of F. hepatica, F. gigantica, or the intermediate Fasciola form irrespective of their origin, demonstrating the usefulness of the mtDNA sequences for the delineation of Fasciola species, and reinforcing the genetic evidence for the existence of the intermediate Fasciola form. 相似文献
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A Ogunrinade 《Research in veterinary science》1979,27(2):238-239
Severe pathological changes were seen in hamsters given metacercariae of Fasciola gigantica irradiated at doses below 4 krads. No adult flukes were recovered from hamsters given metacercariae irradiated at doses above 4 krads and little hepatic damage was caused. It was not ascertained whether resistance resulted following these latter infections. 相似文献