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81.
Gustavo Henrique Batista Lara Clarice Queico Fujimura Leite Alessandro Guazzelli Adolfo Carlos Barreto Santos 《Research in veterinary science》2011,90(2):185-188
Mycobacterium spp. and other pathogens were investigated in 258 swine lymph nodes (129 with and 129 without apparent lesions), and 120 lymph nodes (60 with and 60 without lesions) from wild boars (Sus scrofa). A total of lymph nodes from swine and wild boars were collected of different animals. Submaxillar and mesenteric lymph nodes were submitted to microbiological examination and colonies suggestive of Mycobacterium spp. (alcohol-acid bacilli) were submitted to PCR Restriction Assay (PRA). In swine with lymphadenitis, Mycobacterium spp. (24.1%) and Rhodococcus equi (13.2%) were the most prevalent microorganisms, while in lymph nodes without lesions were identified a complex of microorganisms, including of environmental mycobacteria. In wild boars with lymphadenitis, ß-haemolytic Streptococcus (10.0%), Mycobacterium spp (8.4%) and R. equi (6.6%) were the most frequent. Among mycobacterias were identified predominantly Mycobacterium avium subspecies type 1 (48.3%) and M. avium subspecies type 2 (16.1%), followed by Mycobacterium intracellulare, Mycobacterium szulgai,Mycobacterium fortuitum, Mycobacterium gordonae, Mycobacterium simiae, Mycobacterium nonchromogenicum and Mycobacterium intracellulare type 2. 相似文献
82.
Riccardo Melis Laura Vacca Andrea Bellodi Alessandro Cau Cristina Porcu Maria Cristina Follesa Rita Cannas 《水产资源保护:海洋与淡水生态系统》2020,30(1):86-103
- Genetic information is crucial for the conservation of Dipturus oxyrinchus (Linnaeus, 1758), a threatened large skate with declining populations over most of its geographical range. The main aim of the present study was to investigate the genetic structure, connectivity and demographic history of the longnosed skate in Sardinia (western Mediterranean Sea).
- Patterns of population structure were assessed in 175 specimens from six sampling sites. Variation in two mitochondrial genes (cytochrome c oxidase subunit I (COI) and control region) highlighted high genetic diversity and low but significant genetic differentiation among sites, which clustered into three groups corresponding to the north‐west, north‐east and south Sardinian coasts.
- The observed genetic structuring could presumably depend on a combination of past geological events, contemporary restrictions to dispersal and biological characteristics of the species (e.g. site‐fidelity, no pelagic larval stage, limited dispersal of juveniles and/or adults).
- Demographic analyses showed signs of past population expansion, but substantial current stability of Sardinian populations. From a conservation perspective, these results are encouraging, and indicate that Sardinian populations are still large and stable, and seem not to have suffered negative side‐effects from the ever‐growing fishing pressure in the region.
- The occurrence of genetic structuring strongly supported the close monitoring of populations to identify any erosion of their gene pool, and high genetic variability of the Sardinian D. oxyrinchus populations could thus represent priority populations for conservation purposes, providing potential sources for recolonization in cases of local extinctions in other areas of the distribution range of the species.
- When the sequences from Sardinia were compared with those available from other areas, the data seem to exclude the possibility that the Atlantic and Mediterranean host totally isolated populations or even different species, as recently suggested. However, additional markers and a larger sampling sites are needed to confirm these findings.
83.
84.
da Silva Andrade G Bruhn FR Rocha CM Guimarães Ade S Gouveia AM Guimarães AM 《Veterinary parasitology》2012,188(1-2):168-171
The aim of this study was to determine the prevalence and risk factors associated with infection due to Neospora caninum in serum samples from 488 sheep originating from 63 farms in 63 municipalities distributed across eight of the twelve mesoregions of the state Minas Gerais, southeastern Brazil. For detection of N. caninum the sheep serum samples were subjected to the indirect fluorescence antibody test (IFAT ≥ 50). To identify the risk factors associated with infection due to N. caninum a questionnaire was filled out for each herd by interviewing, the individual responsible for the herd, demanding information on the general characteristics of the property. Sixty-four sheep sera (13.1%; 95% CI=10.3-16.4) presented IgG-specific anti-N. caninum antibodies with the following titers: 50 (49; 76.6%), 100 (7; 10.9%), 200 (4; 6.2%), 400 (3; 4.7%) and 800 (1; 1.6%). The prevalence of infected sheep per mesoregion ranged from 0 to 28.1%. Out of the 63 farms sampled, 31 (49.2%; 95% CI=36.4-62.1) presented at least one seropositive sheep. No significant association was found between the presence of anti-N. caninum antibodies and the risk factors evaluated on the farms, except for the mesoregion variable (p=0.004; OR=0.429; CI95%=0.182-1.008). These results indicate that there is a need for additional research to define the epidemiological importance of this parasite as a cause of reproductive problems in sheep herds in Minas Gerais. 相似文献
85.
Alessandro Marchetti Chiara Piccini Sergio Santucci Igino Chiuchiarelli Rosa Francaviglia 《CATENA》2011,85(3):267-273
Soil surveys are an essential source of information for land management although a limited budget often reduces the amount of data available. Even if the dataset is limited, geostatistics can provide a valid estimation tool through a weighted moving average interpolation (kriging). Often, however, the spatial variability of soil properties appears smoothed and short range variability is underestimated by this kind of interpolation technique. A more realistic distribution of a given variable on the territory can be obtained through models based on stochastic simulation. 相似文献
86.
Simona Valentini Roberto Tamburro Alessandro Spadari Jose Manuel Vilar Giuseppe Spinella 《Journal of Equine Veterinary Science》2010
Ocular ultrasonography in horses represents a valuable imaging diagnostic tool for the diagnosis of intraocular and periocular diseases, particularly when cornea or lens opacities preclude ophthalmoscopy of deeper structures. The authors studied normal and pathological aspects of the eye. Nineteen horses with opacities of the dioptric structures underwent an ultrasound examination. This technique allowed the diagnosis of a posterior synechia (1), cataracts (8), vitreous opacities (6), retinal detachment (3), and a foreign body (1). Ultrasonography provided helpful information about the structure and vascular pattern when the conventional ophthalmic evaluation was unable to achieve a correct diagnosis. 相似文献
87.
Michele R. S. Simões Joal J. B. Leal Alessandro P. Minho Cláudia C. Gomes Michael D. MacNeil Rodrigo F. Costa Vinícius S. Junqueira Patrícia I. Schmidt Fernando F. Cardoso Arione A. Boligon Marcos J. Yokoo 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2020,137(2):177-188
Our goal was to define a breeding objective for Brangus beef cattle in Brazil. Bioeconomic models were produced and used to estimate economic values (EVs). The scenarios simulated were typical full-cycle beef production systems that are used in tropical and subtropical regions. The breeding objective contained pregnancy rate (PR), warm carcass weight (WCW), mature cow weight (MCW), number of nematode eggs per gram of faeces (EPG) and tick count (TICK). Two models were used in series to estimate the EV. A deterministic model was used to simulate effects of PR, WCW and MCW on profitability with a constant parasite load. Subsequently, stochastic models were used to estimate economic values for TICK and EPG as consequences of their environmental effects on weight gains, mortality and health costs. The EV of PR, WCW, MCW, EPG and TICK, was US$1.59, US$2.11, −US$0.24, −US$5.35 and −US$20.88, respectively. Results indicate positive emphasis should be placed on PR (12.49%) and WCW (65.07%) with negative emphasis on MCW (13.92%), EPG (2.77%) and TICK (5.75%). In comparison with the indexes usually used, these results suggest a reformulation in the selection indexes of the beef production system in tropical and subtropical regions in order to obtain greater profitability. 相似文献
88.
三种南方典型水稻土长期试验下有机碳积累机制研究Ⅲ.两种水稻土颗粒有机质结构特征的变化 总被引:3,自引:1,他引:3
采用固体交叉极化魔角自旋13C核磁共振(CPMAS13C-NMR)波谱技术对长期不同施肥处理下红壤性水稻土和太湖地区黄泥土本体土壤以及水稳性团聚体中颗粒有机质(POM)的化学结构特征进行了研究。结果表明,不同施肥处理下本体土壤和不同粒径水稳性团聚体中POM的结构组成相似,主要由烷氧C、烷基C和芳香C组成,其中以烷氧C含量最高。施肥改变了本体土壤POM中各类C原子的相对百分含量,有机肥以及化肥配施有机肥条件下烷氧C含量明显降低,芳香C和酚基C含量有不同程度的增加,表明POM的稳定性增强;单施化肥下烷氧C含量最高,而烷基C、芳香C和芳香度均最低,POM的稳定性减弱,不利于POM的积累。施肥改变了黄泥土不同粒径水稳性团聚体中POM各类C原子的相对百分含量,从而使得不同粒径中POM对其团聚体的稳定性作用发生变化;而红壤性水稻土不同粒径水稳性团聚体POM各类C原子的相对百分含量并未明显受到施肥措施的影响。 相似文献
89.
Alessandro Zotti DVM PHD Chiara Rizzi PHD Gianmaria Chiericato PHD Daniele Bernardini DVM 《Veterinary radiology & ultrasound》2003,44(1):49-52
The right humerus was removed from 30 20-week-old male turkey poults for humerus strength analysis using dual-energy x-ray absorptiometry and humerus-breaking strength. Specimens were cleaned and dried before scanning. To determine the most precise and accurate protocol of bone densitometry analysis for avian long bones, we scanned each specimen using five different techniques, all aimed to simulate soft-tissue thickness. Correlation coefficients and linear regression equations between 1) bone mineral content and humerus ash, and 2) bone mineral density and humerus-breaking strength were estimated with each technique and compared. The coefficient of variation values for precision ranged from 0.40% to 1.69% for bone mineral content and from 0% to 4.19% for bone mineral density. The accuracy was determined by comparing the bone mineral content of each humerus with the corresponding ash weight; the correlation coefficients between the two parameters were highly significant (range 0.949-0.963; P < or = 0.01). Significant correlations were also observed between humerus-breaking strength and bone density measurements (range 0.762-0.785; P < or = 0.01). Linear regression coefficients relating both parameters considered were also highly significant. We concluded that dual-energy x-ray absorptiometry is an accurate and precise method with which to determine ex vivo bone mineral content and strength in turkey bones. Further investigations are requested for field applications of this method to study factors affecting bone physiology and strength. 相似文献
90.