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51.
本文采用粪便直接涂片、浮聚和麦克马斯特法,对采自广州市番禺区欢乐鸟场的17种共183个鹦鹉粪便样品进行了肠道寄生虫感染率反感染强度调查。先后进行了两次采样,检查结果显示:该鸟场养殖的鹦鹉总肠道寄生虫感染率为38.3%。其中吸虫感染比较普遍,感染率达19.1%,其次是绦虫,感染率为10.4%o,线虫和原生动物的感染率分别为9.3%和5.5%。感染强度EPG值随寄生虫和鹦鹉种的不同,在300到2400之间不等。调查中没有发现球虫感染,鉴于调查结果建议对鸟场阳性感染鹦鹉进行针对性驱虫。  相似文献   
52.
自噬(autophagy)是细胞通过降解自身大分子物质或破损细胞器等来维持胞内稳态的一种平衡机制.近年来在顶复门原虫与宿主细胞相互作用研究中发现,顶复门原虫不但可诱导宿主细胞产生自噬并启动天然免疫途径清除寄生虫,亦可进化出独特的机制来抵抗宿主细胞自噬甚至利用其为自身生长提供条件.不同种类顶复门原虫与宿主细胞互作方式不同...  相似文献   
53.
羊消化道的寄生虫病较多,不仅能不同程度地影响羊只的生长发育,降低生产性能,严重的还能造成羊只死亡,对养羊业危害较为严重。笔者概述了羊消化道寄生虫种类及不同地区、季节、年龄羊消化道寄生虫的感染情况,并介绍不同羊消化道寄生虫常用的驱虫药及防治策略。  相似文献   
54.
Zoonoses involving parasites are both common and important, some causing serious diseases. The abilities of such parasites to pass between humans and a variety of vertebrates facilitates their use as experimental model systems. Much can be learned about the host-parasite relationships of zoonotic infections from laboratory-based studies, particularly where it is possible to make use of defined parasite isolates in a variety of host species or in genetically defined strains of a given host. This review focuses on our current understanding of the immunological influences upon host-parasite interactions involving zoonotic parasites and on how such influences are modified by the genetic variability found in populations of both hosts and parasites. Particular emphasis is given to data arising from work with the intestinal parasitic nematode Trichinella spiralis and other isolates of the genus Trichinella.  相似文献   
55.
为了解新疆地区羊驼肠道寄生虫感染情况,采用饱和蔗糖溶液漂浮法和卢戈氏碘液染色法对采自新疆5个养殖基地的185份羊驼新鲜粪便样品进行检查。结果显示:129份样品呈肠道寄生虫阳性,总感染率69.72%;检出8种寄生虫,以球虫为优势感染虫种,感染率57.83%;隐孢子虫、贾第虫、圆线虫、细颈线虫、鞭虫、双腔吸虫和莫尼茨绦虫感染率分别为3.24%、0.54%、15.14%、7.57%、11.35%、1.62%和0.54%。调查表明,新疆地区羊驼肠道寄生虫感染率较高,应加强其检测和防治工作。  相似文献   
56.
Abstract – We explored the incidence of individual feeding specialisation among a naïve predator (non‐native rainbow trout postsmolts) and two native experienced predators (sea‐run Arctic charr and sea‐trout) in a subarctic Norwegian fjord. Interindividual foraging niche stability was obtained by combining information on stomach contents (recent dietary niche) with trophically transmitted parasite infestation (time‐integrated historical dietary niche) of individual predators. Individual fish showed a high degree of resource specialisation as prey items such as gammarids and small fish (both potential intermediate host of parasites) rarely co‐occurred in stomachs. In both naïve and veteran predators, positive associations between the intensity of a specific parasite species and the occurrence of their respective intermediate host (gammarids or fish) in the stomachs of individual predators demonstrated temporally interindividual feeding specialisations. Several behavioural phenotypes clearly co‐existed in both naïve and veteran predator populations, including gammaridivore (benthic feeders), piscivore (pelagic feeders) or insectivore (pleuston feeders) individuals. The likely mechanism of this observed interindividual resource specialisation in the non‐native naïve predators involves a behavioural component of which rapid learning seems to be a key factor.  相似文献   
57.
The anthelmintic resistance status was investigated of nematode parasites of sheep and goats owned by smallholder farmers in communities that received breeding stock from a source where a high level of anthelmintic resistance has been reported. The investigation used the faecal egg count reduction technique, whereby suitable animals within each of eight separate communities were pooled to achieve the numbers required to conduct separate tests for both sheep and goats. Anthelmintics tested were albendazole (ABZ), tetramisole (TET), a combination (ABZ $+$ TET) and ivermectin (IVM), at the manufacturers' recommended dose rates. Results showed that there was no evidence of anthelmintic resistance in nematode parasites of either sheep an goats in any community. This indicates that dilution of resistant parasites imported with introduced breeding stock, and the low selection pressure imposed by the smallholder farmers themselves, has prevented anthelmintic resistance from emerging in nematode parasites of small ruminants in these communities.  相似文献   
58.
Gill parasitic infections challenge farming of rainbow trout (Oncorhynchus mykiss, Walbaum) in freshwater facilities. Apart from flagellates (Ichthyobodo, (Pinto) and ciliates (Ichthyophthirius (Fouquet), Ambiphrya (Raabe), Apiosoma (Blanchard), Trichodinella (Sramek-Husek) and Trichodina (Ehrenberg)), we have shown that amoebae are prevalent in Danish trout farms. Gills were isolated from farmed rainbow trout in six fish farms (conventional and organic earth pond and recirculated systems) and placed on non-nutrient agar (NNA) moistened with modified Neff's amoeba saline (AS) (15°C). Gill amoebae from all examined fish colonized the agar and were identified based on morphological criteria showing species within the genera Trinema (Dujardin) (family Trinematidae), Vannella (Bovee) (family Vannellidae). In addition, hartmannellid amoebae were recorded. We established a monoculture of Vannella sp., confirmed the genus identity by PCR and sequencing and performed an in vitro determination of antiparasitic effects (dose–response studies) of various compounds including sodium chloride (NaCl), hydrogen peroxide, peracetic acid, formalin, aqueous garlic and oregano extracts and a Pseudomonas H6 surfactant. All amoebae were killed in concentrations of 16.90 mg/ml (garlic), 17.90 mg/ml (oregano), NaCl (7.5 mg/ml), hydrogen peroxide (100 µg/ml), peracetic acid (0.03 µg/ml), formaldehyde (25 µg/ml) and the Pseudomonas H6 surfactant (250 µg/ml).  相似文献   
59.
Gallagher CP, Dick TA. Trophic structure of a landlocked Arctic char Salvelinus alpinus population from southern Baffin Island, Canada. Ecology of Freshwater Fish 2010: 19: 39–50. © 2009 John Wiley & Sons A/S
Abstract –  Stable isotopes, diet and parasites were used to investigate the trophic structure of landlocked Arctic char ( Salvelinus alpinus ) from a small Canadian Arctic lake. Two trophic levels of char were identified. The lower trophic level comprised smaller char that consumed mainly invertebrates and harboured low numbers of the cestode plerocercoid Diphyllobothrium spp. while the higher trophic level char were larger, mainly piscivorous and had high numbers of plerocercoids. Procercoids of Diphyllobothrium spp. in copepods are eaten by char where the parasite then differentiates into a plerocercoid. Plerocercoids from smaller fish are transmitted to larger fish by piscivory where they encyst again as plerocercoids until the fish is eaten by a gull. These plerocercoids are a good indicator of trophic level as their numbers accumulate over time in larger fish. The three variables together provided a better resolution of trophic structure than applied separately. For example, plerocercoid numbers plus diet were better predictors of trophic status than stable isotopes in 4–7 year olds, but for char ≥8 years all three variables were complementary. Some char (≥10 years old) were placed in the lower trophic level based on their stable isotope values and had low Diphyllobothrium spp. abundance but were piscivorous and/or cannibalistic. The absence of sexually mature char in the higher trophic group was associated with high numbers of Diphyllobothrium spp. plerocercoids.  相似文献   
60.
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