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American ginseng (Panax quinquefolium) is a medicinal crop which provides tens of millions of dollars in income every year
for Canadian farmers. Most of the ginseng roots are produced in open fields under expensive shade structures. Farmers need
to plant ginseng at a very high density to achieve profitability. Since high planting densities are related to high disease
levels, field-cultivated ginseng requires frequent applications of pesticide. Growing ginseng in forests eliminates the need
of a shade structure and may reduce the need for pesticides. Thus, an experiment was performed in a maple (Acer rubrum) forest
in Québec to evaluate the effects of nutrient inputs such as lime or compost on ginseng development. Ginseng emergence and
survival rates, leaf area and foliar and root weight were evaluated for each treatment. Soil samples were taken in each plot
to determine the concentration of various soil nutrients. During the first two years of the experiment, it was noted that
the application of lime had a significative positive effect on ginseng growth. This effect could be related to higher calcium
concentration and/or lower aluminium toxicity. Liming would be an efficient way to improve the early development of ginseng
in maple forests. This practice is also known to improve the health of maple stands.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
23.
F M Andrews T J Doherty J T Blackford J A Nadeau A M Saxton 《American journal of veterinary research》1999,60(8):929-931
OBJECTIVES: To determine the effects of orally administered omeprazole, as enteric-coated capsules, on baseline and stimulated gastric acid secretion in horses. ANIMALS: 5 healthy 8-year-old mixed-breed horses fitted with gastric cannulas. PROCEDURE: Enteric-coated granules of omeprazole were mixed with corn syrup and administered orally once daily for 5 consecutive days. On days 1 and 5 beginning 5 hours after omeprazole administration, 4 gastric fluid samples were collected, each for 15 minutes, via the gastric cannula (baseline samples). Pentagastrin was administered IV as a constant infusion for the subsequent 2 hours, and 15-minute gastric fluid samples were again collected (stimulated samples). Fluid volume, acidity (mmol H-/L), and pH and gastric acid production (mmol H+) were determined for all baseline samples and for stimulated samples collected during the second hour of pentagastrin infusion. Control experiments were done in a similar manner after giving corn syrup alone to the same horses. RESULTS: Compared with values obtained during control experiments, baseline and stimulated gastric fluid acidity and gastric acid production significantly decreased, and the mean pH of gastric fluid samples significantly increased, after horses were given 5 daily doses of omeprazole. CONCLUSIONS AND CLINICAL RELEVANCE: Enteric-coated omeprazole (1.0 mg/kg of body weight; PO) administered once daily for 5 days significantly inhibited unstimulated and pentagastrin-stimulated gastric acid secretion in horses. This commercially available formulation of omeprazole may be efficacious in the treatment of gastroduodenal ulcers in horses. 相似文献
24.
- 1. The implications of shrinkage associated with desiccation and ethanol preservation for seahorses (genus Hippocampus) were investigated using Hippocampus guttulatus (European long‐snouted seahorse) as a model. Specifically, this research addressed the implications of preservation for taxonomy and life history studies and the application of minimum size limits (MSL) for managing seahorse trade.
- 2. In 2004, the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) listed all seahorse species on its Appendix II, and recommended a 10 cm MSL as an interim means of ensuring sustainable international trade. Inconsistencies in seahorse measurement methods and repeatability posed challenges for applying the MSL. Moreover, the shrinking effect of desiccation on body length observed in other fish was assumed to be negligible for seahorses because of their high degree of ossification.
- 3. Changes in seahorse sizes were measured following immersion in ethanol and desiccation. H. guttulatus shrank on average by 0.1–2.3% when preserved in ethanol and 3.0–6.4% when dried, depending on the trait measured. Similar trends were observed in a sample of H. kuda (yellow seahorse). Specimen posture during drying, and measurement methods also influenced estimates of size.
- 4. Based on the shrinkage observed, 14–44% of captured seahorses that are dried could shrink to below the recommended MSL, even if all seahorses were longer than the MSL at capture. This demonstrates that small changes in body lengths can have significant implications for trade of species managed with size limits.
- 5. Recommendations are to (1) standardize seahorse measurement methods, (2) consider the effects of preservation and measurement technique on body lengths, and apply appropriate corrections in comparative studies and when developing fisheries management strategies, and (3) adjust size limits at the point of capture to ensure retained seahorses comply with the CITES recommended MSL.
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Effects of wilting, ensiling and type of additive on α‐tocopherol and β‐carotene contents in legume–grass mixtures were examined. Swards of birdsfoot trefoil + timothy (Bft + Ti), red clover + timothy (Rc + Ti) and red clover + meadow fescue (Rc + Mf) were harvested as a first regrowth in August 2005. Forage was wilted to a dry‐matter (DM) content of 273 g kg?1 and ensiled without additive or with an inoculant or acid. Wilting decreased α‐tocopherol concentration by 30% in the Bft + Ti mixture (P = 0·015). Untreated Bft + Ti silage had higher α‐tocopherol content than red clover silages (56·9 vs. 34·2 mg kg?1 DM; P = 0·015). The α‐tocopherol concentration of Bft + Ti forages increased during ensiling from 41·1 mg kg?1 DM in wilted herbage to 56·9, 65·2 and 56·8 mg kg?1 DM in untreated, inoculated and acid‐treated silage respectively (P = 0·015). The inoculant increased α‐tocopherol content in the red clover silages (50·1 vs. 34·2 mg kg?1 DM; P = 0·015) compared with untreated red clover silages. Red clover mixtures had lower β‐carotene content than Bft + Ti (32·3 vs. 46·2 mg kg?1 DM; P = 0·016), averaged over treatments. In conclusion, wilting had small effects but the use of bacterial inoculant as an additive and a Bft + Ti mixture increased α‐tocopherol concentration in the silage. 相似文献
27.
Touret M Boysen SR Nadeau ME 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2010,24(6):1458-1461
Background: Cancer is considered a cause of type B hyperlactatemia in dogs. However, studies evaluating cancer as a cause of clinically relevant type B hyperlactatemia (>2.5 mmol/L) are lacking. Cancer cells have a higher lactate production because of increased aerobic glycolysis, known as the “Warburg effect.” The mechanisms through which aerobic glycolysis occurs are not well elucidated, but neoplasia may cause type B hyperlactatemia via this process. Objectives: To determine if malignant tumors of dogs are associated with clinically relevant type B hyperlactatemia (>2.5 mmol/L). Animals: Thirty‐seven client‐owned dogs with malignant tumors: 22 with hematopoietic and 15 with solid tumors. Methods: Histology was used to confirm the diagnosis (cytology was considered adequate for diagnosis of lymphoma). Confounding conditions associated with hyperlactatemia were excluded. Lactate measurements were immediately performed on free‐flow jugular whole blood samples using the LactatePro analyzer. Results: All dogs had lactate concentrations <2.5 mmol/L. Mean blood lactate concentration was 1.09 mmol/L. Mean blood lactate concentrations for solid and hematopoietic tumors were 0.95 and 1.19 mmol/L, respectively. Dogs with lymphoma (n = 18) had a mean blood lactate concentration of 1.15 mmol/L. Conclusions: Malignant tumors were not considered a cause of clinically relevant type B hyperlactatemia. Therefore, cancer‐related type B hyperlactatemia in dogs is uncommon, and hyperlactatemia should prompt careful investigation for causes other than cancer. 相似文献
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Francisco O. Conrado Nicholas Iapoce Mainity Batista-Linhares Sharleen Lopez Morgan H. Matthews Caroline A. McKinney Caitlin Rothacker 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2020,49(4):624-631
An 18-year-old, grey, Thoroughbred Cross gelding was referred to the Cummings School of Veterinary Medicine at Tufts University following a 3-week history of low-grade fever of unknown origin, distal limb swelling, and weight loss. Clinical examination identified a few black, round, smooth nodules along the ventral aspect of the proximal tail. Transabdominal ultrasound showed a markedly enlarged heterogenous spleen, hyperechoic liver nodules, and evidence of peritonitis with fibrin deposition. A mature neutrophilia was noted on complete blood count with variable numbers of phagocytized granules within neutrophils. The granules did not stain with Perl's Prussian blue, and were intensely positive when stained with Fontana-Mason, consistent with melanin. On necropsy, the spleen occupied approximately one-third of the abdominal cavity and was diffusely firm with abundant black pigment on cut section. The medullary space of the 18th thoracic vertebra was also diffusely blackened. The splenic, mediastinal, and tracheobronchial lymph nodes were five times the normal size and diffusely pigmented. The final anatomic diagnosis was disseminated malignant melanoma with extensive splenic involvement and hemolymphatic and vascular neoplastic dissemination. To the authors' knowledge, this is the first full report to identify circulating neutrophils containing phagocytized melanin granules, which confirmed an antemortem diagnosis of disseminated melanoma. 相似文献
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