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391.
França-Silva JC Barata RA Costa RT Monteiro EM Machado-Coelho GL Vieira EP Prata A Mayrink W Nascimento E Fortes-Dias CL da Silva JC Dias ES 《Veterinary parasitology》2005,131(3-4):213-220
A study of Lutzomyia longipalpis (Lutz and Neiva, 1912) (Diptera: Psychodidae), the primary vector of American visceral leishmaniasis (AVL), and the canine form of the disease, was carried out in Porteirinha. The city is situated in the northern part of the Brazilian State of Minas Gerais and is an endemic area of AVL. Systematic phlebotomine captures were performed in seven districts with previously reported cases of canine visceral leishmaniasis, during 2 years (January 2000--December 2001). A total of 2328 specimens of L. longipalpis were captured. The association between the local climate variables and the population density of L. longipalpis was evaluated and rainfall was determined to be a major factor, with increased populations during the rainy season (October--March). At the same time period, blood samples from every dog domiciled in the same seven districts, in total 14,077 animals, were analyzed for infection by viscerotropic Leishmania using indirect immunofluorescence assay (IFA). Accumulated incidence rates of canine VL per district varied from 3.40 to 14.34 for the 2-year period. A positive correlation between the population density of L. longipalpis and the canine cases of visceral leishmaniasis in Porteirinha was observed. 相似文献
392.
Valencáková A Halánová M Bálent P Dvoroznáková E Jamborová E Lesník F Neuschl J Páleník L Cisláková L 《Acta veterinaria Hungarica》2004,52(1):61-69
Several indicators of immune response were observed in immunocompetent mice of the ICR line and those suppressed by dexamethasone upon their experimental infection with the microsporidia of Encephalitozoon cuniculi. The mice were infected by one-shot intraperitoneal administration of 5 x 10(7) pathogenic spores. On Days 7, 14, 28 and 42 after infection, peripheral blood leukocyte phagocytic activity was determined and compared, including phagocytic index and the blastogenic response in spleen cells to mitogenic activation by concanavalin A and phytohaemagglutinin. The results point to the fact that E. cuniculi itself can cause a significant decrease in phagocytic activity of phagocytic leukocytes in the early stages of infection as well as a remarkable decrease in the proliferative response of spleen cells to T-cellular mitogens. 相似文献
393.
394.
A. M. Orsi A. L. Ferreira V. R. de Melo M. M. Valente J. E. Moreira 《Anatomia, histologia, embryologia》1980,9(4):296-301
The connective tissue organization in the epididymus of Didelpbis azarae was studied in paraffin embedded histologic preparations stained with hematoxylin and eosin; Mallory trichrome and Gomori's Nitrous Orcein and Silver stains. Thc connectcve tissue organization is compared with that of other mammals. 相似文献
395.
Erika Geyger 《植物养料与土壤学杂志》1979,142(3):318-329
Soil structure and earthworm activity in a meadow soil in the Soiling area The A-horizon of a Golden Oat Meadow (Trisetetum flavescentis OB) in the Solling was analyzed micromorphologically and micromorphometrically. Five tables with magnifications of the soil structure form an essential part of the presentation. The upper 8-10 cm of the soil consist mainly of earthworm castings with different density of deposition. By these a spongy structure, stable against water, was formed in the upper 3-5 cm of depth. But also in the deeper horizons the soil bulk is penetrated by a net of pores of different width, causing a favourable water capacity as well as allowing sufficient air for the roots. 相似文献
396.
We simulated how possible changes in wind and ground-frost climate and state of the forest due to changes in the future climate may affect the probability of exceeding critical wind speeds expected to cause wind damage within one northern and one southern study area in Sweden, respectively. The topography of the study areas was relatively gentle and the forests were dominated by Norway spruce (Picea abies (L.) Karst.) and Scots pine (Pinus sylvestris L.). Using estimated changes in the net primary production (NPP) due to climate change and assuming a relative change in the site productivity equal to a relative change in NPP, we simulated possible future states of the forest under gradual adjustment of the site index in response to climate change using the model The Forest Time Machine. Global climate change scenarios based on two emission scenarios and one general circulation model were downscaled to the regional level. The modified WINDA model was used to calculate the sensitivity of the forest to wind and the probability of wind damage for individual forest stands for the periods 2011–2041 and 2071–2100 and for a control period 1961–1990. This was done while taking into account effects on stability of the forest from expected changes in the occurrence of ground frost. Increasing sensitivity of the forest to wind was indicated for both study areas when adhering to recommended management rules of today. Adding also a changed wind climate further increased the probability of wind damage. Calculated probabilities of wind damage were generally higher in the southern study area than in the northern one and were explained by differences in wind climate and the state of the forests, for example with respect to tree species composition. The indicated increase in sensitivity of the forest to wind under the current management regime, and possibly increasing windiness, motivate further analysis of the effects of different management options on the probability of wind damage and what modifications of Swedish forest management are possibly warranted. 相似文献
397.
C.S. Dannhauser R.H. Drewes Erika A. van Zyl Christa J. van Rooyen 《African Journal of Range and Forage Science》2013,30(3):179-183
The production and quality of different fodder sorghum and Babala cultivars in the western Transvaal. A number of sorghum cultivars are available commercially, and periodically some cultivars are added while others are withdrawn from the market. The potential yield figures and the nutritive value of these sorghums are generally not known. Owing to erratic availability of seed, only seven cultivars could be established for three consecutive years, while eleven were included in the experiment for at least one year. Babala (SA common) was used as a control, while one imported Babala cultivar (Hypearl) was evaluated for one year. Yields varied so much over the experimental period that no cultivar could be singled out as the highest yielder. Of the seven cultivars grown for three years, the dry matter (DM) yields were ranked in the following order of magnitude: PNR 989, Domor, Babala (SA common), Supergraze, Gotcha, Mixed sorghum and PNR 841. In terms of leaf production, the highest to the lowest yielding cultivars were the following: Babala (SA common), PNR 841, Mixed sorghum, Supergraze, PNR 989, Gotcha and Domor. In vitro dry matter digestibility and crude protein content showed little variation between cultivars. 相似文献
398.
Brito EH Fontenelle RO Brilhante RS Cordeiro RA Soares Júnior FA Monteiro AJ Sidrim JJ Rocha MF 《Veterinary journal (London, England : 1997)》2007,174(1):147-153
Yeasts of the genera Candida and Malassezia can be found as commensal microorganisms in animals. The main species of importance in veterinary medicine are Malassezia pachydermatis and Candida albicans. The objectives of this study were to conduct a phenotypic characterization and to evaluate the in vitro antifungal sensitivity of strains of C. albicans (n=5), C. tropicalis (n=3) and M. pachydermatis (n=32) isolated from dogs. The phenotyping was based on macro and micromorphological features as well as biochemical analysis. The techniques of microdilution in broth and dilution in agar were used to evaluate the in vitro sensitivity of Candida spp. and M. pachydermatis, respectively. The tested drugs were ketoconazole (KTC), itraconazole (ITC), fluconazole (FLC) and amphotericin B (AMB). The morphological analysis of the strains of Candida spp. and M. pachydermatis did not show any noteworthy alterations when compared to standard strains. On the other hand, in the biochemical tests, 34.4% of the strains of M. pachydermatis were negative for the urease test. Four strains of C. albicans were resistant to FLC with a minimum inhibitory concentration (MIC) >64microg/mL and all were resistant to KTC and ITC (MIC>16microg/mL). The MIC for two strains of C. tropicalis were >16microg/mL for KTC and ITC, and >64microg/mL for FLC. It is worth highlighting that all of the strains tested were sensitive to AMB with the MIC varying from 0.25-1.0microg/mL. All strains of M. pachydermatis were sensitive to ITC with a minimum fungistatic concentration (MFC) 0.0075microg/mL. The MIC for 29 strains was the same (MFC0.0075microg/mL) for KTC. The MFCs for FLC varied from 1 to 16microg/mL, and for AMB, the MFC interval was 0.125-8microg/mL. There were no alterations in the classic phenotypic features of the strains of Candida spp. and M. pachydermatis isolated from dogs but, unlike M. pachydermatis, Candida spp. were much more resistant to azole antifungal agents. 相似文献
399.
400.
Marcos H. Soares Gustavo A. Rodrigues Lívia M. R. Barbosa Dante T. Valente Júnior Felipe C. Santos Gabriel C. Rocha Paulo H. R. F. Campos Alysson Saraiva 《Animal Science Journal》2020,91(1)
To evaluate the effects of crude protein (CP) and lactose (LAC) for weaned piglets on performance, intestinal morphology, and expression of genes related to intestinal integrity and immune system, 144 piglets with initial weight 7.17 ± 0.97 kg were allotted in a randomized design, in a 2 × 3 factorial arrangement (20.0% and 24.0% CP and 8.0%, 12.0%, and 16.0% LAC) with eight replicates. Piglets fed 20.0% CP had greater weight gain and feed intake. Including 12.0% LAC in the 20.0% CP diet provided higher villous height in the duodenum than 8.0% LAC, and 12.0% or 16.0% LAC in the 24.0% CP diet resulted in higher villous height in the jejunum and ileum, and higher villi/crypt ratio in the ileum than 8.0% LAC. No effects of CP and LAC on interleukin‐1β and tumor necrosis factor‐α mRNA were observed. The 16.0% LAC diet provided higher gene expression of transforming‐β1 growth factor. Feeding 20.0% CP resulted in better performance than 24.0% CP. The 12.0% LAC diet promoted greater genetic expression of occludin and zonula occludens. Including 12.0% LAC in the diet may improve intestinal epithelial morphology and integrity, and these improvements are more evident when piglets are fed diets with 24.0% CP. 相似文献