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71.
The incidence of sooty blotch/flyspeck (SBFS) and bitter and bull’s eye rots were assessed in a Fuji apple orchard during two seasons. Using a regular sampling design, 252 trees were selected and 20 fruits per tree were sampled at harvest and scored for disease incidence. For bitter and bull’s eye rots, additional assessments were made on all symptomless fruit after a 30‐day period of storage. Randomness in the spatial pattern was assessed using beta‐binomial analysis of incidence data for three sampling scales (one, three or six adjacent trees as sampling units) and using Spatial Analysis by Distance Indices (sadie ) for disease counts for the 3‐tree sampling scale. sadie was also used for testing spatial associations between a pair of diseases, between years for the same disease or between rotted and latently infected fruit. Using a toroidal‐shifts procedure, 360 maps of disease counts were created based on the observed data, which were further analysed using sadie . Most datasets showed an aggregated spatial pattern, which was more consistent for the two fruit rots than SBFS, which showed distinct patterns depending on the year or method of analysis. The two fruit rots were spatially associated in most situations but SBFS and bull’s eye rot were dissociated in one season. Results from virtual orchards showed that the patterns observed in the original maps may accurately represent those in similar apple‐growing areas. Hypotheses regarding aspects of ecology and epidemiology of pathogens studied and potential efficacy of control measures in the region are discussed.  相似文献   
72.
In this study, two populations of dogs with pituitary dependent hypercortisolism (PDH) were compared over a 2-year period. One group had normal vision (Group A, n=27) and one group was blind (Group B, n=20). Group B was characterised by the rapid appearance of the clinical signs of PDH that precede blindness. We found increases in pre-adrenocorticotropic hormone cortisol (P=0.002), IL-6 (P=0.0001), insulin, and insulin sensitivity (detected with the Homeostatic Model Assessment, P<0.0001) in Group B but not in Group A. The nitric oxide (NO) and the total adiponectin concentrations decreased (P=0.0001 and P=0.02, respectively) in Group B versus Group A. The IL-6 and insulin concentrations and the HOMA-A index were positively correlated with the cortisol concentration and were negatively correlated with the NO concentration. With the exception of adiponectin, the other variables were associated with blindness. We concluded that blindness in PDH is a haemodynamic event associated with metabolic changes, with the increase in the IL-6 concentration and the decrease in the NO concentration affecting the retinal vasculature and producing a high risk of vision loss.  相似文献   
73.
This study was carried out to develop and characterize mouse monoclonal antibodies (mAbs) against chicken CD83 (chCD83), a membrane-bound glycoprotein belonging to the immunoglobulin superfamily that is primarily expressed on mature dendritic cells (DCs). A recombinant chCD83/IgG4 fusion protein containing the extracellular region of chCD83 was expressed in Chinese Hamster Ovary (CHO) cells and isolated from the spent cell culture medium by protein G affinity chromatography. The extracellular region of the chCD83 protein was purified and used to immunize mice. A cell fusion was performed, from which 342 hybridomas were screened for mAbs to chCD83. Two mAbs, chCD83-159 and chCD83-227, stained the greatest percentage of chCD83-transfected CHO cells and were selected for further characterization. By flow cytometry, both mAbs reacted with a chicken macrophage cell line, HD11. Both mAbs also recognized a single 53 kDa protein on Western blots of lysates from lipopolysaccharide-stimulated spleen mononuclear cells or unstimulated HD11 cells. Immunostaining of chicken secondary lymphoid organs identified chCD83(+) cells with morphologic and subtissue localization properties comparable to mammalian DCs. In vitro stimulation of spleen mononuclear cells with concanavalin A (Con A) decreased the percentage of chCD83(+) cells compared with cells treated with medium alone. Interestingly, spleen cells treated with Con A in the presence of chCD83-227 mAb exhibited decreased percentage of MHCII(+) cells compared with cells treated with an isotype-matched negative control mAb. These chCD83 mAbs may be useful for future investigations of chicken immune cell maturation and mechanisms of action.  相似文献   
74.
Rabbits absorb more calcium (Ca) from their diet than they require, and excrete surplus via urine, which therefore contains a typical 'sludge'. This makes rabbits susceptible to Ca-containing uroliths. But given the Ca content of diets of free-ranging specimens, and the limited reports of urinary sludge and Ca contents in free-ranging lagomorphs, we can suspect that rabbits are naturally adapted to high urinary Ca loads. We fed four groups of New Zealand hybrid rabbits [n = 28, age at start 5-6 weeks) pelleted diets consisting of lucerne hay only (L, Ca 2.32% dry matter (DM)], lucerne:oats 1:1 (LG, Ca 1.36%), grass hay only (G, Ca 1.04%), or grass:oats 1:1 (GG, 0.83%) for 25 weeks, with water available ad libitum. Diets were not supplemented with Ca, phosphorus, or vitamin D. Rabbits on diets LG and GG had lower food and water intakes, lower faeces and urine output, grew faster and had higher body mass at slaughter (mainly attributable to adipose tissue). Apparent Ca digestibility decreased in the order L-LG-G/GG. Rabbits on L had larger and heavier kidneys, more urinary sediment at sonography, and a higher urinary Ca content than the other groups. No animal showed signs of urolithiasis/calcinosis at X-ray, sonography, or gross pathology. Kidney/aorta histology only sporadically indicated Ca deposits, with no systematic difference between groups. Under the conditions of the experiment, dietary Ca loads in legume hay do not appear problematic for rabbits, and other factors, such as water supply and level of activity may be important contributors to urolithiasis development in veterinary patients. However, due to the lower Ca content of grass hay, the significantly lower degree of urinary sludge formation, and the significantly higher water intake related with grass hay feeding, grass hay-dominated diets are to be recommended for rabbits in which urolithiasis prevention is an issue.  相似文献   
75.
Aquaculture is one of the main sources of income in many countries worldwide. Intensive farms are often affected by different infectious diseases that can decrease their final production. To control this situation, several antibiotics are frequently used with known environmental consequences. The aim of this study was to analyze different bacterial strains isolated from of gilthead sea bream, sea bass, sole and meagre guts, for use as probiotics in aquaculture. The strains were evaluated in vitro through various mechanisms of selection, such as the production of antagonistic effects against pathogens, production of antibacterial substance, adhesion to the intestinal mucus, competition for nutrients or binding site, and growth in intestinal mucus. A total of 50 bacterial strains were analyzed and only one showed excellent in vitro results for consideration as a candidate to be analyzed in vivo. The strain, identified as Vagococcus fluvialis, showed good protection against Vibrio anguillarum 975-1 in vivo in the experimental challenge, showing a relative percent survival of 42.3% higher than positive control group. Therefore, in conclusion we consider this strain to be a good candidate for use as a future probiotic in aquaculture.  相似文献   
76.
ABSTRACT: BACKGROUND: Phloem-feeding insects are among the most devastating pests worldwide. They not only cause damage by feeding from the phloem, thereby depleting the plant from photo-assimilates, but also by vectoring viruses. Until now, the main way to prevent such problems is the frequent use of insecticides. Applying resistant varieties would be a more environmental friendly and sustainable solution. For this, resistant sources need to be identified first. Up to now there were no methods suitable for high throughput phenotyping of plant germplasm to identify sources of resistance towards phloem-feeding insects. RESULTS: In this paper we present a high throughput screening system to identify plants with an increased resistance against aphids. Its versatility is demonstrated using an Arabidopsis thaliana activation tag mutant line collection. This system consists of the green peach aphid Myzus persicae (Sulzer) and the circulative virus Turnip yellows virus (TuYV). In an initial screening, with one plant representing one mutant line, 13 virus-free mutant lines were identified by ELISA. Using seeds produced from these lines, the putative candidates were re-evaluated and characterized, resulting in nine lines with increased resistance towards the aphid. CONCLUSIONS: This M. persicae-TuYV screening system is an efficient, reliable and quick procedure to identify among thousands of mutated lines those resistant to aphids. In our study, nine mutant lines with increased resistance against the aphid were selected among 5160 mutant lines in just 5 months by one person. The system can be extended to other phloem-feeding insects and circulative viruses to identify insect resistant sources from several collections, including for example genebanks and artificially prepared mutant collections.  相似文献   
77.
Objective To evaluate the pre‐emptive analgesic effect of pre‐incisional epidural ketamine. Study Design A blinded, randomized experimental study. Animals Sixteen mixed breed mares, 7.6 ± 2.8 years old, weighing 352 ± 32 kg. Methods In a pilot study, an incision was made on one lateral thigh using a lidocaine block and no further analgesics, and it was verified that the nociceptive threshold was lower on the incised side than nonincised side (p ≤ 0.05), and that von Frey filaments evoked a pain response. The 16 animals were divided into group A (ketamine, n = 9) and B (saline, n = 7). An epidural catheter was inserted 24 hours before the trials. The thigh was shaved bilaterally, and the right side was blocked (incised side) using lidocaine. Twenty‐five minutes later, ketamine (A) or saline (B) was administered epidurally. Five minutes later, a 10‐cm skin incision was made on the right side, and then sutured. Nociceptive threshold was determined with von Frey filaments at 1, 3, and 5 cm around the incision at 15‐minute intervals for 2 hours, then at 4, 6, and 8 hours. Behavioral alterations, heart and respiratory rates were recorded. Nociceptive thresholds from these points were averaged to obtain mean values at each time, converted to a logarithmic scale, and submitted to a nonparametric analysis (Mann–Whitney and one‐way repeated measures anova test, p ≤ 0.05). Results After 8 hours, the global range score revealed reduced hyperalgesia (p < 0.01) around the incision in 92% (4.65–4.27) of evaluated intervals in group A (ketamine). There were no significant changes in behavior, heart and respiratory rates. Conclusions It was concluded that pre‐emptive epidural ketamine reduced post‐incisional pain in the horse, and that von Frey filaments were able to quantify cutaneous sensitivity after tissue damage. Clinical relevance Epidural ketamine injection can reduce post‐incisional sensitivity in the horse.  相似文献   
78.
A new commercially available ELISA (ELISAr-Chlamydia) for detecting antibodies against Chlamydophila abortus has been evaluated using sheep field serum samples. The ELISA is based on a recombinant antigen which expresses part of a protein from the 80-90kDa family that is specific to C. abortus. Sera (105) from six flocks with confirmed ovine chlamydial abortion (OEA) outbreaks were used in this study, as well as sera (258) from 18 flocks which had suffered no OEA in the last lambing. The ELISAr-Chlamydia was compared with the complement fixation test (CFT) and with an ELISA using purified C. abortus elementary bodies (ELISA-EB), employing as reference technique a comparative microimmunofluorescence test that differentiates C. abortus infection from Chlamydophila pecorum infection. The results showed that the sensitivity of ELISAr-Chlamydia was 90.9% with a specificity of 85.9%, the sensitivity of CFT was 71.0% with a specificity of 83.6%, while the sensitivity of ELISA-EB was 95.2% and the specificity was 54.2%. Furthermore, ELISAr-Chlamydia was the test with fewer false positives resulting from positive reactivity to C. pecorum, although 15% of the sera positive for C. pecorum but negative for C. abortus antibodies reacted positively. This study demonstrated with field material that ELISAr-Chlamydia provides the most balanced results between sensitivity and specificity, especially in flocks with no clinical OEA but reactivity to C. abortus.  相似文献   
79.
Coffee is globally one of the most important export crops and is a prominent part of the economy in more than 50 countries in Latin America, Africa and Asia. In Colombia, it has been the leading export commodity for more than a century. However, genetic research on coffee has been rather sparse and mainly focused on the two major cultivated species, Coffea arabica L. and C. canephora P., leaving unexplored the genetic potential in other species. In this study, an interspecific mapping population consisting of 101 F1 hybrid plants from a cross between the diploid species C. liberica and C. eugenioides was evaluated for genetic segregation at 618 molecular marker loci. Of these, 168 SSRs and two ESTs exhibited polymorphic patterns that allowed segregation analysis and genetic linkage estimations. A genetic map consisting of 146 co-dominant loci and 11 predicted linkage groups was constructed using the mapping software JoinMap 3.0. The conjoined maternal/paternal map length is 798.68 cM, has an average saturation density of 6.01 cM/interval, and covers an estimated 66–86 % of the diploid coffee genome. Approximately 24 % of loci had null alleles, and 23.5 % exhibited segregation distortion. Knowledge derived from this study has important applications for quantitative trait locus analysis and marker-assisted selection in Colombian coffee breeding programs.  相似文献   
80.
Hewson, J., Johnson, R., Arroyo, L. G., Diaz‐Mendez, A., Ruiz‐López, J. A., Gu, Y., del Castillo, J. R. E. Comparison of continuous infusion with intermittent bolus administration of cefotaxime on blood and cavity fluid drug concentrations in neonatal foals. J. vet. Pharmacol. Therap.  36 , 68–77. Healthy neonatal foals were treated with cefotaxime by bolus (40 mg/kg IV q6h for 12 doses; n = 10) or by infusion (loading dose of 40 mg/kg IV followed by continuous infusion of a total daily dose of 160 mg/kg per 24 h for 3 days; n = 5). Population pharmacokinetics was determined, and concentrations in cavity fluids were measured at steady state (72 h). Highest measured serum drug concentration in the bolus group was 88.09 μg/mL and minimum drug concentration (Cmin) was 0.78 μg/mL at 6‐h postadministration (immediately before each next dose), whereas infusion resulted in a steady‐state concentration of 16.10 μg/mL in the infusion group. Mean cefotaxime concentration in joint fluid at 72 h was higher (P = 0.051) in the infusion group (5.02 μg/mL) compared to the bolus group (0.78 μg/mL). Drug concentration in CSF at 72 h was not different between groups (P = 0.243) and was substantially lower than serum concentrations in either group. Insufficient data on pulmonary epithelial lining fluid were available to compare the methods of administration for cefotaxime in this cavity fluid. Results support continuous drug infusion over bolus dosing in the treatment for neonatal foal septicemia to optimize time that cefotaxime concentration exceeds the minimum inhibitory concentration of common equine pathogens.  相似文献   
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