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A study was carried out to assess the efficacy and the economic profit of prophylactic treatment against Isopsora suis with toltrazuril or with a sulfamethazine/trimethoprim combination in piglets from an intensive pig farm. Thirty-one litters were included in study. Eight litters were treated once with toltrazuril (20 mg/kg b.w.) at 3 days of age (Toltra group); 8 litters were treated with the sulphonamide combination (sodium sulfamethazine 35 mg and trimethoprim 7 mg/kg b.w.) for 3 consecutive days starting at 3 days of age (Sulfa group), and 15 litters were untreated (control group). Counts of oocyst per gram on pooled feces sampled from each litter were carried out on Days 7, 14, 21 and 28 and diarrhea was registered daily from pooled samples. Piglets were weighed on Days 1, 7 and 28 and mean weight gain (WG) and daily weight gain (DWG) were evaluated. The economic profit of treatment was evaluated comparing the WG of piglets of each treatment group from the day of birth to Day 28. On Days 14, 21 and 28, toltrazuril showed a better efficacy in controlling fecal oocyst output, diarrhea and weight gain compared with sulphamidic treatment (P < 0.001). The budgeting analysis showed a return of economic benefit of € 0.915 per toltrazuril-treated piglets and an additional cost of € 1.155 per sulphonamide-treated piglets.  相似文献   
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The morphological and structural features of the vascular component of the bursa of Fabricius in the duck are described. By means of an intravasal perfusion of suitably colored neoprene Latex or Microscopaque, or a perfusion of Indian ink, it was possible to follow visually the routes of arteries, veins and the microcirculation; this last represents a major characteristic of the bursal follicle in the duck. The microcirculation has its origins in several roots arising from the follicular arterioles, which in the region of the cortex constitute an open vascular layer. From these pre-capillary arterioles, adjacent to the limiting layer between cortex and medulla, a dense capillary network is formed. With the aid of an electron microscope the presence of a cortico-medullary barrier of an epithelio-reticular nature was revealed; close to it there are the terminal branches of the intrafollicular network. The barrier appears to be structurally more compact than that of the cortical capillaries of the mammalian thymus.  相似文献   
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Trichoderma in its natural environment competes for nutrient uptake and is required to protect itself from adverse natural toxic compounds, such as those produced by plants and other microbes in the soil community, or synthetic toxic compounds released human activity. One of the most important metabolic pathways for drug resistance and substrate uptake, both in prokaryotes and eukaryotes, is ATP dependent. The role of ABC transporter proteins in the biology of Trichoderma is still not kno…  相似文献   
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Trichoderma strains are used in agriculture because they provide to the plants the following benefits: i) are rhizosphere competence and establish stable rhizosphere microbial communities; ii) control plant disease caused by pathogenic and competitive microflora, by using a variety of mechanisms; iii) improve vegetative growth, root development and yield; iv) make nutrients more available to the plant. In this work we have investigated the ability of T. harzianum T22 and T. atroviride P…  相似文献   
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The molecular factors involved in the three-way interaction between plant, pathogenic fungi and antagonistic/biocontrol fungi, such as Trichoderma, are still poorly understood, even if they represent a matter of interest for improving crop management and developing new strategies for plant diseases control. The aim of this work is to investigate the components involved in this interaction and, for this purpose, a proteomic approach was used. 2-D maps of the protein extracts from the single co…  相似文献   
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In the late 1980‘ s the development of a severe epidemic of green mold caused by Trichoderma spp.was noted in the commercial production of Agaricus bisporus (champignon) in the United Kingdom,North America, Spain and Holland, which caused extensive economic losses. The parasitic fungi  相似文献   
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Decline induced by Chalara fraxinea is an emerging disease that severely affects ash stands in Europe. The disease appears to have an invasive spread from East to West of Europe in the last decade. The teleomorphic stage, Hymenoscyphus pseudoalbidus, that occurs as apothecia on ash rachis in the litter was recently described. The origin of ash decline remains unclear as a cryptic species, H. albidus, a long-established fungus in Europe, could be present in the same niche, and as in Switzerland, H. pseudoalbidus was shown to have been present long before the recent epidemic outbreak. In France, the emerging disease is very recent and clearly restrained to Northeastern France. We thus collected isolates from infected hosts and from apothecia/ash rachis both inside and outside the infected area in France in order to compare them on the basis of pathogenicity towards ash seedlings and sequences of the ITS regions and of three single-copy genes. We showed that two population types exhibiting about 2% base pair polymorphism in the sequences analysed were present in Northern France. The first type, corresponding to H. pseudoalbidus, was present on rachis and infected hosts only in Northeastern France and showed strong pathogenicity towards ash seedlings in inoculation tests. By contrast, the second type, which corresponds to H. albidus, was present throughout Northern France and showed no pathogenicity towards ash seedlings. Our study confirms the results of Queloz et al. (2010) who presented molecular evidences for the existence of two cryptic species, H. albidus and H. pseudoalbidus. The results strongly suggest that Chalara fraxinea/H. pseudoalbidus is a recent invader in France.  相似文献   
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The goat choroid plexus angioarchitecture of the lateral ventricles was studied under the SEM using the method of “microvascular corrosion casts”. The whole plexus is semilunar shaped and directed in an antero-posterior, latero-median fashion. In the plexus the lateral extremity is larger than the median one. All the components of the vascular bed (arteries, venes and capillaries) of the choroid plexus have interesting morpho-structural features. In particular, the capillaries are more developed than the other components and they are variously located on both sides of the plexus. The capillary network has a various organization in different zones of each side of the plexus.  相似文献   
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