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431.
Infectious diseases can cause large health problems in cattle. The infections cause an acute inflammatory response, mediated by pro-inflammatory cytokines such as IL-1beta, IL-6 and TNF-alpha. By mapping the pattern of cytokines during inflammations, valuable information about the course of an infection is gained. The aim of the present study was to evaluate a particle-based flow cytometric method, the xMAP technique, using ovine/bovine reagents, for quantification of IL-1beta, IL-6 and TNF-alpha, for application in studies on ruminant infectious diseases with emphasis on bovine milk and plasma samples. Singleplex, duplex and triplex xMAP assays were evaluated, and limits of detection (LODs) as well as intra- and inter-assay variabilities were determined for each assay. Cross-reactivity between reagents in multiplex assays was also tested. In addition, presence of cytokines in milk and plasma samples from healthy and mastitic cows was studied. The LODs were significantly lower for singleplex xMAP assays than for duplex and triplex assays. In singleplex assays, the LODs were 0.08, 0.2 and 0.5 ng/ml, for IL-1beta, IL-6 and TNF-alpha, respectively. Corresponding LODs in triplex assays were 2.0, 6.5 and 3.5 ng/ml. Data indicate that the linear ranges of the multiplex assays were narrower than in singleplex assays. The intra-assay coefficients of variation were < or =10.7% for singleplex assays, while they ranged from 6.2 to 23.2% in the triplex assay. The inter-assay variance ranged from 5.1 to 35.8% in singleplex assays, and from 8.8 to 78.4% in triplex assays. Cross-reactivity between reagents was not observed, and all three cytokines were detected in bovine milk and plasma samples collected from cows with clinical mastitis. In conclusion, our results show that the xMAP technique can be used for quantification of IL-1beta, IL-6 and TNF-alpha in bovine samples, and that further work is required to optimize the multiplex assays.  相似文献   
432.
Streptococcus suis is a major pathogen in pigs and causes significant morbidity and mortality in herds world-wide. A major problem with S. suis is the presence of asymptomatic carrier animals which can spread the organism within and between herds. The palatine tonsil is one of the main sites where the organism can be recovered, both in infected and carrier animals. The use of multiple-colour immunohistology allowed identification of the cell types associated with bacteria in the tonsils of infected gnotobiotic piglets. Bacteria were never associated with T-cells or B-cells but were always associated with cells of the myeloid lineage. Expression of CD16 and CD163 on these leukocytes suggested an association with mature macrophages in tonsil, which may lead to clearance or control of the micro-organism.  相似文献   
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OBJECTIVE: To compare the effects of two balanced anaesthetic protocols on end-tidal isoflurane (Fe'ISO), cardiopulmonary performance and quality of recovery in horses. DESIGN: Prospective blinded randomized clinical study. ANIMALS: Sixty-nine client-owned horses, American Society of Anesthesiologists category I and II, undergoing elective surgery. METHODS: The horses were premedicated with acepromazine (0.03 mg kg(-1)) IM 30-60 minutes before induction of anaesthesia and were randomly assigned to one of two treatments: in group L (37 horses) xylazine (1 mg kg(-1)) and in group M (31 horses) medetomidine (7 microg kg(-1)) was administered IV for sedation. Anaesthesia was induced 5 minutes later with ketamine (2.2 mg kg(-1)) and diazepam (0.02 mg kg(-1)) IV and maintained with isoflurane in oxygen/air (initial FIO2 0.40-0.50) and a constant rate infusion (CRI) of either lidocaine (2 mg kg(-1)/15 minutes loading dose followed by 50 microg kg(-1) minute(-1)) (group L) or medetomidine (3.5 microg kg(-1) hour(-1)) (group M). If horses showed movement or nystagmus, additional thiopental or ketamine was administered. Heart rate, mean arterial pressure (MAP), Fe'ISO and arterial blood gases were measured. Cardiac output was measured with the lithium dilution method in 10 (group L) and 11 (group M) horses every 45 minutes. Recovery was scored. RESULTS: Heart rate and the cardiac index (CI) were significantly higher in group L with changes over time. In group M, MAP was significantly higher during the first 50 minutes. Group L needed more additional ketamine and thiopental to maintain a surgical plane of anaesthesia and Fe'ISO was significantly higher from 70 minutes. Recovery was longer in group M and of better quality. The significance level was set at p < 0.05. CONCLUSIONS AND CLINICAL RELEVANCE: In group M, maintenance of stable anaesthetic depth was easier and lower Fe'ISO was required to maintain a surgical plane of anaesthesia. Recoveries were longer but of better quality. The CI was higher in group L but cardiovascular function was generally well maintained in both groups.  相似文献   
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ObjectiveTo assess the potential of a thermal carbon dioxide (CO2) laser to explore antinociception in pain-free cats.Study designExperimental, prospective, blinded, randomized study.AnimalsSixty healthy adult female cats with a (mean ± standard deviation) weight of 3.3 ± 0.6 kg.MethodsCats were systematically allocated to one of six treatments: saline 0.2 mL per cat; morphine 0.5 mg kg−1; buprenorphine 20 μg kg−1; medetomidine 2 μg kg−1; tramadol 2 mg kg−1, and ketoprofen 2 mg kg−1. Latency to respond to thermal stimulation was assessed at baseline and at intervals of 15–30, 30–45, 45–60, 60–75, 90–105 and 120–135 minutes. Thermal thresholds were assessed using time to respond behaviourally to stimulation with a 500 mW CO2 laser. Within-treatment differences in response latency were assessed using Friedman’s test. Differences amongst treatments were assessed using independent Kruskal–Wallis tests. Where significant effects were identified, pairwise comparisons were conducted to elucidate the direction of the effect.ResultsCats treated with morphine (X2 = 12.90, df = 6, p = 0.045) and tramadol (X2 = 20.28, df = 6, p = 0.002) showed significant increases in latency to respond. However, subsequent pairwise comparisons indicated that differences in latencies at specific time-points were significant (p < 0.05) only for tramadol at 60–75 and 90–105 minutes after administration (21.9 and 43.6 seconds, respectively) in comparison with baseline (11.0 seconds). No significant pairwise comparisons were found within the morphine treatment. Injections of saline, ketoprofen, medetomidine or buprenorphine showed no significant effect on latency to respond.Conclusions and clinical relevanceThe CO2 laser technique may have utility in the assessment of thermal nociceptive thresholds in pain-free cats after analgesic administration and may provide a simpler alternative to existing systems. Further exploration is required to examine its sensitivity and comparative utility.  相似文献   
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Sesame (Sesamum indicum L.) is one of the most important ancient oilseed crops grown throughout the tropical and subtropical regions of the world. In Uganda, most of the cultivated sesame varieties are local landraces which are frequently traded between farmers. Although these traditional landraces are an important source of genetic diversity, knowledge of their genetic diversity is still limited.Agromorphological traits and a set of published and newly developed microsatellite markers were analyzed on a collection of 121 accessions of Ugandan sesame landraces. CpSSR analysis revealed four haplotypes, whereby haplotype B was present in 96% of the individuals. The analysis of nSSR markers from 6 non-coding regions revealed a mean PIC value of 0.56 whereas the PIC value of eight selected EST-derived SSRs was 0.26. Accession-wise, the expected heterozygosity (He) varied from 0 to 0.396. AMOVA revealed that the majority of the variance occurred among the individuals accounting for 75% of the total variation, only 6% was attributed to differences among the districts, pointing towards a high gene flow (Nm = 4.476). These results are supported by the PCoA analysis as well as the NJ tree both of which revealed no clustering of the accessions according to their geographic origin. Also the statistical analysis of 10 agromorphological traits indicated no clear pattern related to the geographic origin. Such a poor grouping, indicative of considerable gene flow across geographic domains, could be explained either by a high outcrossing rate, and/or through extensive seed trading.  相似文献   
440.
Feeding by pine weevil (Hylobius abietis L.) causes severe damage to newly planted conifer seedlings in most parts of Scandinavia. We investigated the effect of planting time and insecticide treatment on pine weevil damage and seedling growth. The main objective was to study if planting in early autumn on fresh clear-cuts would promote seedling establishment and reduce the amount of damage caused by pine weevil the following season. The experiment was conducted in southern Sweden and in south-eastern Norway with an identical experimental design at three sites in each country. On each site, Norway spruce seedlings with or without insecticide treatment were planted at four different planting times: August, September, November and May the following year. In Sweden, the proportion of untreated seedlings that were killed by pine weevils was reduced when seedlings were planted at the earliest time (August/September) compared to late planting in November, or May the following year. This pattern was not found in Norway. The average length of leading shoot, diameter growth and biomass were clearly benefited by planting in August in both countries. Insecticide treatment decreased the number of seedlings killed or severely damaged in both Norway and Sweden.  相似文献   
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