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41.
Sikasunge CS Phiri IK Phiri AM Siziya S Dorny P Willingham AL 《Veterinary journal (London, England : 1997)》2008,176(2):240-244
Tongue examination and detection of circulating antigen (Ag-ELISA) were used to establish the prevalence of Taenia solium porcine cysticercosis in free-range pigs in selected districts of Eastern, Southern and Western provinces of Zambia, and to determine if prevalence of porcine cysticercosis was associated with age, breed and sex. Households with pigs were identified using the snowballing technique. A total of 1691 pigs were examined out of which 183 (10.8%) were positive on tongue examination. Ag-ELISA gave a sero-prevalence of 23.3%. When considering the factors in a logistic regression analysis, only breed type was significantly associated with porcine cysticercosis (OR=0.72; 95%CI=0.63-0.81). The crossbred pigs were 72% more likely to have had cysticercosis than the Nsenga (dwarf local) breed as determined by Ag-ELISA. The result that crossbred pigs had a higher prevalence of T. solium cysticercosis suggests that pig breeds may display different susceptibility to cysticercosis. The limited use of latrines in these areas implies that people use the nearby bush for defecation, resulting in pigs having access to human faeces. Therefore, investigation of taeniosis and cysticercosis in humans is warranted to better comprehend the local epidemiology and transmission risks. This should then be followed by extension programs to communities so that the control plans that could be instituted are more sustainable. 相似文献
42.
The Geological Surveys of Finland and Norway, and the Central Kola Expedition, Russia, carried out an environmental geochemical mapping project, including investigation of stream water quality. The project was carried out in 1992–1993 in the border areas of Finland, Norway and Russia, covering an area of 12 000 km2, to determine the impacts of smelting industries at Nikel and Zapoljarnij. Stream water was one of eight different indicators providing an estimation of the degree and distribution of contamination in the study area. Contamination of surface water was assessed by analyses of 44 samples, 41 variables were measured on each sample. Indicators of human activities in surface waters are NO3, K, electrical conductivity (EC), SO4, Na, Cl and acidification indicated by alkalinity and pH. On the coast Na and Cl contents are also affected by marine salts. The results show considerably higher contents of K, Ca, Mg, SO4, Na, heavy metals and EC in the samples close to Nikel and Zapoljarnij smelters than those sites more distant from the polluting sources. Especially chemical effects of high emissions of Ni, Cu and SO2 on stream water quality from Nikel and Zapoljarnij smelters are clearly seen near the sources of emissions. 相似文献
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45.
S. Ansari‐Mahyari P. Berg M.S. Lund 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2009,126(6):443-454
In fine mapping of a large‐scale experimental population where collection of phenotypes are very expensive, difficult to record or time‐demanding, selective phenotyping could be used to phenotype the most informative individuals. Linkage analyses based sampling criteria (LAC) and linkage disequilibrium‐based sampling criteria (LDC) for selecting individuals to phenotype are compared to random phenotyping in a quantitative trait loci (QTL) verification experiment using stochastic simulation. Several strategies based on LAC and LDC for selecting the most informative 30%, 40% or 50% of individuals for phenotyping to extract maximum power and precision in a QTL fine mapping experiment were developed and assessed. Linkage analyses for the mapping was performed for individuals sampled on LAC within families and combined linkage disequilibrium and linkage analyses was performed for individuals sampled across the whole population based on LDC. The results showed that selecting individuals with similar haplotypes to the paternal haplotypes (minimum recombination criterion) using LAC compared to random phenotyping gave at least the same power to detect a QTL but decreased the accuracy of the QTL position. However, in order to estimate unbiased QTL parameters based on LAC in a large half‐sib family, prior information on QTL position was required. The LDC improved the accuracy to estimate the QTL position but not significantly compared to random phenotyping with the same sample size. When applying LDC (all phenotyping levels), the estimated QTL effect were closer to the true value in comparison to LAC. The results showed that the LDC were better than the LAC to select individuals for phenotyping and contributed to detection of the QTL. 相似文献
46.
Brun-Hansen HC Kampen AH Lund A 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2006,35(2):182-187
BACKGROUND: Age-related changes in hematologic values are known to occur in many species. Few published studies include repeated measurements of hematologic parameters in calves during the first months of life. OBJECTIVE: The aim of the present study was to monitor hematologic values by sequential measurements from birth to 6 months of age in 15 healthy calves of the Norwegian Red breed, and compare the results to reference intervals for adult, lactating dairy cows. METHODS: Fifteen clinically healthy calves were sampled every week during the first 5 weeks of life and every month thereafter until 6 months of age. Hematologic values were measured using the ADVIA 120 hematology system. Reference intervals were determined for 75 healthy adult cows of the same breed. RESULTS: Compared with adult reference intervals, the MCV was lower and the RBC count was higher in calves throughout the investigation period. Hemoglobin concentration stayed largely within the adult reference interval. Mean MCHC was lower than adult values for 5 weeks, then increased and reached adult values by weeks 10-12. The mean lymphocyte count for calves reached adult reference values at weeks 6-8, and the mean monocyte count increased steadily until weeks 14-16. For most leukocytes, interindividual variation was larger during the first 5-8 weeks of life. The mean platelet count for calves was higher than the adult reference interval until weeks 19-21 of age. CONCLUSIONS: Age-specific reference intervals for calves from birth to 6 month of age are needed for RBC count, MCV, MCHC, red cell distribution width, and platelet and lymphocyte counts. 相似文献
47.
Zhi-Qiang Chen Karl Lundén Bo Karlsson Ingrid Vos Åke Olson Sven-Olof Lundqvist Jan Stenlid Harry X. Wu María Rosario García Gil Malin Elfstrand 《European Journal of Forest Research》2018,137(4):517-525
Infections with Heterobasidion parviporum devalue the Norway spruce timber as the decayed wood does not meet the necessary quality requirements for sawing. To evaluate the incorporation of disease resistance in the Norway spruce breeding strategy, an inoculation experiment with H. parviporum on 2-year-old progenies of 466 open-pollinated families was conducted under greenhouse (nursery) conditions. Lesion length in the phloem (LL), fungal growth in sapwood (FG) and growth (D) were measured on an average of 10 seedlings for each family. The genetic variation and genetic correlations between both LL, FG and growth in the nursery trial and wood quality traits measured previously from 21-year old trees in two progeny trials, including solid-wood quality traits (wood density, and modulus of elasticity) and fiber properties traits (radial fiber width, tangential fiber width, fiber wall thickness, fiber coarseness, microfibril angle and fiber length). For both LL and FG, large coefficients of phenotypic variation (>?26%) and genetic variation (>?46%) were detected. Heritabilities of LL and FG were 0.33 and 0.42, respectively. We found no significant correlations between wood quality traits and growth in the field progeny trials with neither LL nor FG in the nursery trial. Our data suggest that the genetic gains may reach 41 and 52% from mass selection by LL and FG, respectively. Early selection for resistance to H. parviporum based on assessments of fungal spread in the sapwood in nursery material, FG, will not adversely affect growth and wood quality traits in late-age performance. 相似文献
48.
Benkwitz F Nicolau L Lund C Beresford M Wohlers M Kilmartin PA 《Journal of agricultural and food chemistry》2012,60(25):6293-6302
In this study three different approaches were employed to identify key odorants in Sauvignon blanc wines. First, the concentrations of the odorants were compared to their respective aroma detection thresholds. The resulting odor activity values (OAV) were transformed into a normalized and weighted measure that allows the aroma profiles of different wines to be compared and the contribution of a single aroma in a complex mixture to be evaluated. Based on their OAV, 3-mercaptohexanol and 3-mercaptohexyl acetate were the two most important aroma compounds in many Marlborough Sauvignon blanc wines. Due to limitations with the OAV approach, the study was extended to include aroma extract dilution analysis (AEDA), which revealed that β-damascenone, together with the varietal thiols, esters, and higher alcohols, are key odorants in Sauvignon blanc wines. The final approach undertaken was aroma reconstitution and omission tests using a deodorized wine base and the creation of a model Marlborough Sauvignon blanc. Single compounds and groups of compounds were omitted from the model to study their impact on the sensory properties of the model wine. Reconstitution and omission confirmed that varietal thiols, esters, terpenes, and β-damascenone are all important contributors to Sauvignon blanc aroma. The methoxypyrazines showed an important but relatively low impact in all three of the approaches undertaken in this study. 相似文献
49.
Current progress in cancer treatment has increased the incidence of long-term patient survival. Ovarian tissue cryopreservation (OT) is still the most promising fertility saving method offered to young female patients with cancer prior to the onset of radio-chemotherapy. Further follicular development of immature primordial follicles depends on transplantation or in vitro culture (IVC). Aim of this study was to evaluate the appropriateness of cryopreserved ovine OT with 1,2-propanediol (PROH) after short-term IVC and xenotransplantation (XT). Ovarian tissue fragments from young adult sheep were cryopreserved using a standard slow-freezing protocol with 1.5 M PROH. Cryopreserved OT was assessed by light- and transmission electron microscopic analyses after thawing, IVC or XT in severe immunodeficient mice. Control OT showed the presence of healthy preantral follicles (Mean: 78.8%; SE 2.9%) and normal structure of the stromal tissue. After thawing and IVC over 80% of damaged primordial follicles and poor preservation of the stromal tissue was observed. After XT, OT demonstrated deficient follicles and huge areas of vacuolization in the stromal tissue confirmed by ultrastructural assessment. In conclusion, because of the irreversible character of the follicular and stromal damage of cryopreserved ovine ovarian tissue after IVC and XT, strong improvement of the utilized protocol is needed to be suitable for the preservation of ovine ovarian tissue. The deleterious effects of PROH do not imply its exclusion as cryoprotectant, but more research is needed for the development of less toxic cryoprotectant mixtures and toxicity neutralizers with attested cryoprotectant capacity for the safe and feasible freezing of human ovarian tissue. 相似文献
50.
Glickman LT Glickman NW Moore GE Lund EM Lantz GC Pressler BM 《Preventive veterinary medicine》2011,99(2-4):193-200
Naturally occurring periodontal disease affects >75% of dogs and has been associated with cardiac lesions and presumptive endocarditis. However, the relationships between periodontal disease and chronic kidney disease (CKD) in dogs have not been studied. In a retrospective longitudinal study the incidence of azotemic CKD was compared between a cohort of 164,706 dogs with periodontal disease and a cohort of age-matched dogs with no periodontal disease from a national primary care practice. These dogs contributed 415,971 dog-years of follow-up from 2002 to 2008. Hazard ratios and 95% confidence intervals from Cox regression were used to compare the incidence of azotemic CKD in dogs with stage 1, 2, or 3/4 periodontal disease to dogs with no periodontal disease. The hazard ratio for azotemic CKD increased with increasing severity of periodontal disease (stage 1 hazard ratio=1.8, 95% confidence interval: 1.6, 2.1; stage 2 hazard ratio=2.0, 95% confidence interval: 1.7, 2.3; stage 3/4 hazard ratio=2.7, 95% confidence interval: 2.3, 3.0; P(trend)=<0.0001) after adjustment for age, gender, neuter status, breed, body weight, number of hospital visits, and dental procedures. Increasing severity of periodontal disease was also associated with serum creatinine >1.4 mg/dl and blood urea nitrogen >36 mg/dl, independent of a veterinarian's clinical diagnosis of CKD. 相似文献