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991.
Chantelle Franklin Michael Herrtage Karen Harris Marie-Aude Genain 《Veterinary radiology & ultrasound》2023,64(2):194-200
Humeral intracondylar fissures (HIF) have been predominantly reported in spaniel breeds and proposed to be possible risk factors for humeral condyle fractures (HCF). We hypothesized that the prevalence of incidental HIF in French Bulldogs may be greater than that of other brachycephalic breeds. A retrospective, observational, prevalence study was performed using CT examinations of French bulldogs and other brachycephalic breed dogs presenting for an unrelated condition. Two European College of Veterinary Diagnostic and Imaging-certified radiologists reviewed the images of the humeral condyles of these dogs. A classification system was devised to grade the findings. We considered a Score 1 to be normal, Score 2 to have centralised sclerosis, Score 3 to have a partial fissure and Score 4 to have a complete fissure. A total of 228 elbows were reviewed from 122 dogs. Of this population, 145 elbows were from French Bulldogs, 54 were from Pugs, and the remainder were from a mix of other brachycephalic breeds. The prevalence of HIF (score 3 or 4) in elbows of the French bulldog, pug and other breed groups was 6.9% (CI 2.8–11%), 5.6% (CI 0–11.7%), and 3.4% (CI 0–10.15%), respectively. At a dog level, the prevalence of HIF (score 3 or 4 present in at least one elbow) was found to be 11.8% (CI 4.6–19%) in French Bulldogs, 11.1% (CI 0–22.9%) in Pugs, and 5.26% (CI 0–15%) in the other breed group. There was no significant difference between the breed groups. The inter-reviewer reliability for CT scoring of HIF based on Cohen's weighted kappa was low at 0.19. 相似文献
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Effect of Timing and Nitrogen Fertilizer Application on Winter Oilseed Rape (Brassica napus L.). I. Growth Dynamics and Seed Yield 总被引:1,自引:0,他引:1
The field experiments conducted on the grey‐brown podzolic soil in the four growing seasons (1998–2001) at Krzeslice Farm, central‐western Poland comprised seven fertilization variants: 80NF + 80CAN; 80CAN + 80CAN; 80AN + 80AN; 80NF + 50CAN + 30CN; 80CAN + 50CAN +30CN; 80AN + 50AN + 30CN (where NF – nitrofos NPK; CAN – calcium‐ammonium nitrate; AN – ammonium nitrate; CN – calcium nitrate) and control (without N) applied in split rates at the beginning of spring regrowth (80 kg N ha?1), stem elongation (80 or 50) and flower buds visible stages (30). The yielding effect of tested fertilization variants was significant in comparison with the control (2.24 t ha?1). The highest mean seed yield (3.64 t ha?1) was collected from 80AN + 80AN and 80CAN + 80CAN variants. Mean values of 4 years indicate that the second N rate division (80 + 50 + 30) decreased yield, although not significantly in comparison with these two N treatments. Plants grown on these treatments have developed different patterns of growth to yield the seeds. These patterns were characterized by very high crop growth rate during flowering (above 21 g m?2 day?1) and negative at maturation (down to ?2.5 g m?2 day?1). Plants fertilized with ammonium nitrate (80AN + 80AN) reached maximum growth rate earlier (65 days), which lasted longer (20 days) than plants fertilized with calcium‐ammonium nitrate (71 days lasting 17.5 days). Plants grown on the control treatment reached the highest crop growth rate within 79 days (14.8 g m?2 day?1), which lasted 15 days. 相似文献
998.
The use of overhead trellis systems for the production of dry-on-vine (DOV) raisins and table grapes in California is expanding. Studies were conducted from 2006 to 2009 using Thompson Seedless grapevines grown in a weighing lysimeter trained to an overhead arbor trellis and farmed as DOV raisins for the first two years and for use as table grapes thereafter. Maximum canopy coverage for the two lysimeter vines across years was in excess of 80 %. Seasonal (15 March–31 October) evapotranspiration for the lysimeter vines (ETLys) was 952 mm in 2007 (farmed as DOV raisins) and 943 and 952 mm (when farmed as table grapes). The maximum crop coefficient (K cLys) across all 4 years ranged from 1.3 to 1.4. These maximum values were similar to those estimated using the relationship where K c is a function of the amount of shaded area measured beneath the canopy at solar noon (K c = 0.017 × percent shaded area). Covering the lysimeter’s soil surface with plastic (and then removing it) numerous times during the 2009 growing season (1 June–14 September) reduced ETLys from an average of 6.4 to 5.6 mm day?1 and the K c from 1.07 to 0.93. A seasonal basal K c (K cb) was calculated for grapevines using an overhead trellis system with a 13 % reduction in the K cLys across the growing season. 相似文献
999.
Irrigation systems aim to meet multiple objectives and performance must therefore be assessed using quantifiable measures for each. It therefore becomes an extremely difficult task to capture the valuation of all of them simultaneously and to mentally process the trade-offs between them in order to arrive at an overall impression of system performance. There is a need for a methodology which provides a systematic approach to comparing and combining the components of overall performance.Multi-Attribute Utility Theory offers an attractive approach to assessing performance of irrigation systems in the form of a utility function which reflects the strength of preferences and trade-offs between individual performance criteria. The method is described and demonstrated on the basis of a case study of irrigation in Sudan. 相似文献
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Summary Traffic during alfalfa harvest operations can cause soil compaction and damage to newly growing stems. Root exploration for soil water and nutrients, forage growth dynamics, and final yield can all be affected. The objectives of this study were to determine the long-term effects of harvest traffic and soil compaction on water-use efficiency (WUE) of alfalfa grown in a Wasco sandy loam (coarse-loamy, mixed, nonacid, thermic Typic Torriorthents). Alfalfa was planted into tilled soil and managed with or without harvest traffic. Plants subjected to traffic during harvest had a significantly lower WUE two out of the three years studied compared to plants that were never subject to traffic. The second experiment examined whether planting alfalfa into compacted soil and managed with or without harvest traffic altered WUE. Soil compaction had no affect on alfalfa WUE. It was significantly lower when grown in compacted soil and subjected to harvest traffic. It is suggested that the decrease in WUE caused by harvest traffic may be explained by plants allocating carbohydrates to damaged shoots and crowns instead of to above ground forage production. The area of the field affected by harvest traffic, which damages newly growing stems, should be minimized to increase crop water use efficiency. 相似文献