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Plant Foods for Human Nutrition - There is great interest in the search for new alternatives to antimicrobial drugs, and the use of prebiotics and probiotics is a promising approach to this...  相似文献   
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We summarize the current knowledge on parasitism‐related invasion processes of the globally invasive Rattus lineages, originating from Asia, and how these invasions have impacted the local epidemiology of rodent‐borne diseases. Parasites play an important role in the invasion processes and successes of their hosts through multiple biological mechanisms such as “parasite release,” “immunocompetence advantage,” “biotic resistance” and “novel weapon.” Parasites may also greatly increase the impact of invasions by spillover of parasites and other pathogens, introduced with invasive hosts, into new hosts, potentially leading to novel emerging diseases. Another potential impact is the ability of the invader to amplify local parasites by spillback. In both cases, local fauna and humans may be exposed to new health risks, which may decrease biodiversity and potentially cause increases in human morbidity and mortality. Here we review the current knowledge on these processes and propose some research priorities.  相似文献   
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Objective Canine leishmaniosis is a disease characterized by the wide distribution of the parasite throughout the tissues of the host. The purpose of this study was to describe the presence of Leishmania spp. and associated inflammation in ocular‐associated muscles of dogs with patent leishmaniosis. Procedures Smooth muscles (iris dilator muscle, iris sphincter muscle, ciliary muscle, Müller muscle, smooth muscle of the periorbita and smooth muscle of the nictitating membrane) and striated muscles (orbicularis oculi muscle, obliquus dorsalis muscle and dorsal rectus muscle) were evaluated. Routine staining with hematoxylin and eosin and immunohistochemistry to detect Leishmania spp. were performed on tissue sections. Results Granulomatous inflammation was seen surrounding muscular fibers and was composed mainly of macrophages with scattered lymphocytes and plasma cells. This infiltrate could be seen in 52/473 (10.99%) samples of smooth muscle and 36/142 (25.35%) samples of striated muscle. Parasites were detected in 43/473 (9.09%) samples of smooth muscle and in 28/142 (19.71%) samples of striated muscle. Conclusions To the authors’ knowledge, this is the first report assessing the presence of Leishmania spp. and associated infiltrate in intraocular, extraocular and adnexal smooth and striated muscles. The inflammation present in those muscles could contribute to clinical signs already described, such as blepharitis, uveitis, and orbital cellulitis.  相似文献   
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Tropical Animal Health and Production - Bovine brucellosis is a zoonotic disease that causes great economic losses. The disease is endemic in Colombia and animal movements from infected herds carry...  相似文献   
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Lectins are plant secondary metabolites (PSM) found in many forages and which may confer anthelmintic properties to gastrointestinal parasites through disrupting the development of parasitic larvae throughout its life cycle. In experiment 1, the ability of the plant lectins jacalin (JAC), concanavalin A (Con A), phytohemagglutinin E2L2 (PHA-E2L2), phytohemagglutinin L4 (PHA-L4), phytohemagglutinin E3L (PHA-E3L), kidney bean albumin (KBA), Robinia pseudoacacia agglutinin (RPA), Maackia amurensis lectin (MAA), Maclura pomifera agglutinin (MAA), Dolichos biflorus agglutinin (DBA), wheat germ agglutinin (WGA) and Galanthus nivalis agglutinin (GNA) to disrupt the feeding of the first stage larvae (L(1)) of the sheep gastro-intestinal nematodes (GIN) Teladorsagia circumcincta, Haemonchus contortus and Trichostrongylus colubriformis was investigated using a larval feeding inhibition test (LFIT). Only PHA-E3L, WGA and Con A had a potent effect on disrupting larval feeding of all of the three species of GIN investigated. The lectin concentration required to inhibit feeding in 50% of L(1) (IC50) was 7.3±1.2, 8.3±1.4 and 4.3±1.7 μg/ml for PHA-E3L; 59.1±32.4, 58.7±11.9 and 8.1±7.0 μg/ml for Con A and 78.9±11.2, 69.4±8.1 and 28.0±14.1 μg/ml for WGA for T. circumcincta, H. contortus and T. colubriformis larvae, respectively (P=0.006). The addition of the lectin inhibitors fetuin, glucose/mannose or N-acetylglucosamine for PHA-E3L, Con A and WGA, respectively, caused an increase in the proportion of larvae that had fed at all concentrations for PHA-E3L only. In experiment 2, the effect of extracts from the tropical plants Azadiractha indica, Trichanthera gigantea, Morus alba, Gliricidia sepium and Leucaena leucocephala on the feeding behaviour of H. contortus L(1,) was examined. A. indica, T. gigantea and M. alba failed to inhibit 50% of larvae from feeding at concentrations up to 10mg plant extract per ml. In contrast, both G. sepium and L. leucocephala demonstrated a dose-dependent effect on larval feeding with respective IC50 estimates (mean±s.e.) of 0.015 mg/ml ±0.001 and 3.465 mg/ml ±0.144, effects which were partly reversed by the inclusion of either the tannin inhibitor polyethylene glycol or the lectin inhibitor Fetuin. These studies demonstrate that plant lectins can have an inhibitory effect on the feeding behaviour of first stage larvae of ovine GIN in vitro. Moreover they also provide novel evidence that lectins may contribute to the anthelmintic properties of some tropical forage plant extracts, such as G. sepium and L. leucocephala.  相似文献   
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