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21.
Rice dwarf virus isolates were collected from several locations in Japan, the Philippines, China, Nepal and Korea. Genomic dsRNA segment profiles in polyacrylamide gel electrophoresis differed among the isolates. There were less differences in the profiles between isolates from Japan and Korea than in those between these two Countries and others. Nucleic acid hybridization was used to examine the extent of genomic variation. Full-length cDNAs to all genomic segments encoding non-structural proteins (S4, S6, S9, S10, S11 and S12) were synthesized from two Japanese isolates, and were used for dot-blot hybridization. Hybridizations using probes generated from the full-length cDNA clones failed to differentiate isolates from different geographical areas. However, cDNA probes covering a variable region of S12 were able to distinguish Japanese and Korean isolates from those of other countries. Phylogenetic tree analysis based on the amino acid sequence of P12 encoded by S12 grouped Japanese and Korean isolates together. The Chinese isolates from two different locations (Yunnan and Fujian) were closely related to each other, and were the most distantly related to Japanese and Korean isolates.  相似文献   
22.

Objectives

(1) To collect the perceptions of veterinarians performing equine castrations in Australia on techniques, preferences and outcomes, (2) to investigate veterinarian use and experience with the Henderson castrating instrument and (3) to investigate potential associations between demographics, castration methods and techniques, and complications.

Design

Online survey of members of the Australian Veterinary Association’s Special Interest Group, Equine Veterinarians Australia (EVA).

Methods

A link to the survey was included in the EVA e‐newsletter and practices on the EVA website were contacted by telephone and follow‐up email. Fisher’s exact test was used to determine associations between ligation and complications. A generalised linear model with a negative binomial family was used to determine associations between count response variables and categorical independent variables.

Results

Responses were obtained from 138 veterinarians (response rate, 13.1%) who performed 5330 castrations over 12 months. Castrations were most commonly performed in the field, on anaesthetised horses, using emasculators, via an open approach and without ligation of the spermatic cord. Estimated complications after use of emasculators were swelling (25%), haemorrhage (5%) and infection (5%). The Henderson instrument was used by approximately 10% of respondents and its use for castration was associated with fewer reports of postoperative swelling compared with emasculators (P = 0.002). Rates of evisceration with the Henderson and emasculator methods were comparable (0.43% and 0.9%, respectively).

Conclusion

Castration preferences varied widely among survey participants. Reported complication types and rates were comparable to those reported previously in other countries. Perceptions that the Henderson instrument was associated with less swelling should be investigated further via a prospective controlled investigation.  相似文献   
23.
Essential oils are widely used in the pharmaceutical, food and cosmetic industries, and many plant essential oils have shown that they have positive effects on broilers nutrition. This experiment was conducted to study the effects of orally administered different dosages of carvacrol essential oils on intestinal barrier function in broiler chickens. A total of eighty 28‐day‐old (1.28 ± 0.15 kg) ROSS 308 broilers were randomly allocated to four groups of 20 replicates each, with one chicken per replicate per cage, and all were fed with the same diet. Four experimental groups were orally administered 0, 200, 300 or 400 μl carvacrol essential oils at 18:00 hr every day during the 2‐week experimental period. As a result of which, the gene expression of the occludin, claudin‐1, claudin‐5, ZO‐1 and ZO‐2 in intestinal mucosa of small intestine (p < 0.05) and the goblet cell content in small intestine epithelium (p < 0.05) were significantly increased; test subjects with 300 or 400 μl carvacrol essential oils reduced the microbial counts of Salmonella spp. and Escherichia coli in the intestines (p < 0.05); Essential oils administration also significantly increased activity of the sucrase (p < 0.05) and lactase (p < 0.05) in intestinal mucosa. In conclusion, the carvacrol essential oils have positive effects on growth performance and intestinal barriers function of broilers; those effects may be related to the dosage, as administration of 300 or 400 μl was more effective than that of 200 μl.  相似文献   
24.
25.
This study was conducted to evaluate the influence of seed priming on drought tolerance of pigmented and non‐pigmented rice. Seeds of pigmented (cv. Heug Jinju Byeo) and non‐pigmented (cv. Anjoong) rice were soaked in water (hydropriming) or solution of CaCl2 (osmopriming). Seeds were sown in soil‐filled pots retained at 70 (well‐watered) and 35% (drought) water‐holding capacity. Drought stress caused erratic and poor stand establishment and decreased the growth of both rice types. More decrease in plant height and leaf area under drought stress was noted in pigmented rice, whereas decrease in root length and seedling dry weight, under drought, was more obvious in non‐pigmented rice. Pigmented rice maintained more tissue water and photosynthesis and had more polyphenols, flavonoids and antioxidant activity than non‐pigmented rice. Seed priming was effective in improving stand establishment, growth, polyphenols, flavonoids and antioxidant activity; however, extent of improvement was more in pigmented rice under drought. In conclusion, drought caused erratic germination and suppressed plant growth in both rice types. However, pigmented rice had better drought tolerance owing to uniform emergence, and better physiological and morphological plasticity. Seed priming was quite helpful in improving the performance of both rice types under drought and well‐watered conditions.  相似文献   
26.
This study was conducted to evaluate the effects of dietary supplementation of Barodon, an anionic alkali mineral complex, on growth, feed utilization, humoral innate immunity and disease resistance of olive flounder. A basal experimental diet was used as a control and supplemented with 0.1, 0.2, 0.3, 0.4, or 0.5% Barodon. Triplicate groups of fish (26.4 ± 0.2 g) were fed one of the diets to apparent satiation twice daily for 10 wk. The growth performance was enhanced (P < 0.05) linearly and quadratically in fish fed diets containing Barodon compared with that in fish fed the control. Feed utilization was significantly improved by Barodon supplementation. Serum lysozyme and antiprotease activities were increased quadratically in Barodon fed groups. Also, significantly higher superoxide dismutase activity was found in Barodon‐fed fish. Dietary supplementation of 0.1–0.3% Barodon resulted in significant enhancement of fish disease resistance against Streptococcus iniae. The findings in this study indicate that dietary supplementation of Barodon can enhance growth, feed utilization, innate immunity, and disease resistance of olive flounder and that the optimum level seems to be 0.1% in diets.  相似文献   
27.
Salinity reduces crop yield by limiting water uptake and causing ion‐specific stress. Soybean [Glycine max (L.) Merr.] is sensitive to soil salinity. However, there is variability among soybean genotypes and wild relatives for salt tolerance, suggesting that genetic improvement may be possible. The objective of this study was to identify differences in salt tolerance based on ion accumulation in leaves, stems and roots among accessions of four Glycine species. Four NaCl treatments, 0, 50, 75 and 100 mm , were imposed on G. max, G. soja, G. tomentella and G. argyrea accessions with different levels of salinity tolerance. Tolerant genotypes had less leaf scorch and a greater capacity to prevent Na+ and Cl? transport from soil solution to stems and leaves than sensitive genotypes. Magnitude of leaf injury per unit increase in leaf Na+ or Cl? concentrations was lower in tolerant than in susceptible accessions. Also, plant injury was associated more with Na+ rather than with Cl? concentration in leaves. Salt‐tolerant accessions had greater leaf chlorophyll‐meter readings than sensitive genotypes at all NaCl concentrations. Glycine argyrea and G. tomentella accessions possessed higher salt tolerance than G. soja and G. max genotypes.  相似文献   
28.
An 8-year-old neutered male Yorkshire Terrier dog presented with head pressing, vestibular ataxia, neck tenderness, and no oculocephalic reflex. A demarcated lesion in the pons was identified on MRI. The patient was tentatively diagnosed with a glioma and was treated with hydroxyurea plus imatinib and prednisolone. After 30 days of therapeutic treatment, the patient showed a clear improvement in neurological signs, which lasted for 1117 days. On day 569 after the initiation of treatment, 18F-fluorodeoxyglucose (FDG)-positron emission tomography (PET) was performed with no significant findings on visual analysis. The average and maximal standardized uptake values (SUVs) were 1.92 and 2.29, respectively. The tumor-to-normal-tissue (T/N) ratio was 0.97. The first evidence of clinical deterioration was noticed on day 1147. On day 1155, 3,4-dihydroxy-6-[18F]-fluoro-l-phenylalanine (18F-FDOPA)-PET was performed. High uptake of 18F-FDOPA was observed in the intracranial lesion. The mean and maximal SUVs of the tumor were 1.59 and 2.29, respectively. The T/N ratio was 2.22. The patient was euthanized on day 1155 and histopathologic evaluations confirmed glioma (astrocytoma). This case shows that chemotherapy with hydroxyurea plus imatinib may be considered in the treatment of canine glioma. Furthermore, this is the first case describing the application of 18F-FDG and 18F-FDOPA in a dog with glioma.  相似文献   
29.
Salvia reflexa (lance-leaf sage)-contaminated alfalfa hay was fed to ~500 mixed-breed beef cattle. Within hours of exposure, nearly half of the cattle developed lethargy, anorexia, depression, and recumbency, followed by bellowing, colic, and death. Even though the uneaten contaminated hay was removed the first day, nearly 100 animals died within the first 48 h. Three of these cattle were examined postmortem, and tissues and hay samples were collected for microscopic and chemical analysis. Several days later, a smaller number of the clinically poisoned cattle developed neurologic disease with aberrant behavior, aggression, icterus, blindness, exhaustion, and death. A total of 165 cattle were fatally poisoned. Poisoned cattle had swollen, dark, mottled livers that had a prominent nutmeg-like lobular pattern on cut section. Histologically, there was severe centrilobular-to-panlobular hepatic necrosis with marked hepatocellular swelling, degeneration, and necrosis. The surviving cattle developed liver disease characterized by altered serum biochemical analyses and microscopic hepatocellular degeneration and necrosis. In subsequent biopsies and analysis, these lesions resolved within 6–7 mo. After confirming toxicity of the hay in cattle, goats, and mice, followed by a mouse bioassay–guided chemical fractionation process, Salvia reflexa was identified as the contaminant in the hay responsible for the hepatotoxicity. S. reflexa has not been reported previously to cause fatal hepatotoxicity in livestock in North America, to our knowledge.  相似文献   
30.
ObjectiveTo describe an approach for ethmoidal nerve block (EBLOCK) and to compare the effects of a maxillary nerve block (MBLOCK), EBLOCK and their combination (M-EBLOCK) on heart rate (HR), systolic (SAP), mean (MAP), diastolic (DAP) arterial pressures and respiratory rate (fR) during nasal stimulation in dogs.Study designProspective, blinded, randomized, crossover placebo-controlled study.AnimalsBeagle dogs (five cadavers, nine live dogs), with a median (interquartile range) weight of 10.5 (10.3–11.0) kg.MethodsThe accuracy of iohexol injections (each 1 mL) at the maxillary and ethmoidal foramina in cadavers was evaluated using computed tomography. Then, anesthetized dogs were administered four bilateral treatments separated by 1 week, saline or 2% lidocaine 1 mL per injection: injections of saline at the maxillary and ethmoidal foramina (Control), injections of lidocaine at the maxillary foramina and saline at the ethmoidal foramina (MBLOCK), injections of saline at the maxillary foramina and lidocaine at the ethmoidal foramina (EBLOCK) and injections of lidocaine at all foramina (M-EBLOCK). The ventral nasal meatus was bilaterally stimulated using cotton swabs, and HR, SAP, MAP, DAP and fR were continuously recorded. Values for each variable were compared before and after stimulation using Wilcoxon signed-rank test. Changes in variables among treatments were analyzed using Mann–Whitney U and Kruskal–Wallis tests (p ≤ 0.05).ResultsComputed tomography revealed iohexol distribution around the openings of the target foramina in all cadavers. In living dogs, HR, SAP, MAP, DAP and fR significantly increased after stimulation within each treatment (p < 0.03). Physiologic responses were significantly attenuated, but not absent, in the M-EBLOCK [HR (p = 0.019), SAP, MAP, DAP and fR (all p ≤ 0.001)] compared with those in the Control.Conclusions and clinical relevanceConcurrent injections of lidocaine at the maxillary and ethmoidal foramina attenuated HR, arterial pressure and fR responses to nasal stimulation in Beagle dogs.  相似文献   
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