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61.
BACKGROUND: A major global challenge is to provide agricultural production systems that are able to sustain growing demands for food, feed, fibre and renewable raw materials without exacerbating climate change. Detailed and reliable data on the CO2 balance of different agricultural management activities and inputs as a basis to quantify carbon footprints of agriculture are still lacking. This study aims to fill this gap further by quantifying the net balance of emitted and assimilated CO2 due to the application of crop protection treatments on the farm, and by assessing their partial contribution to GHG emissions and mitigation in agriculture. The study focuses on key agricultural crops including wheat, corn, oilseeds and sugar crops. RESULTS: The final CO2 balance, considering GHG emissions due to on‐farm CPP treatment in comparison with CO2 storage in additional biomass, CO2 protected with respect to agrotechnical inputs and land inputs and CO2 saved with respect to associated global land use changes, is positive and may reach multiples of up to nearly 2000. CONCLUSION: The results highlight the importance of the positive yield effects of the CPP programme applications on the farm, resulting in additional assimilated biomass at the farm level and less land use changes at the global level, and thus lower pressure on environmentally important indicators of overall agricultural sustainability. Copyright © 2012 Society of Chemical Industry 相似文献
62.
K Hirschvogel K Jurina TA Steinberg LA Matiasek K Matiasek E Beltrán A Fischer 《Journal of the American Animal Hospital Association》2012,48(5):299-309
Treatment of dogs with acute canine polyradiculoneuritis (ACP) is restricted to physical rehabilitation and supportive care. In humans with Guillain-Barré syndrome, the counterpart of ACP, randomized trials show that IV immunoglobulin (IVIg) speeds recovery. The authors of the current study hypothesized that dogs with ACP would tolerate IVIg well and recover faster than dogs managed with supportive treatment only. Sixteen client-owned dogs with ACP were treated with IVIg, and 14 client-owned dogs served as a retrospective control group. Diagnosis was confirmed using clinical features, electrodiagnostics, cerebrospinal fluid analysis, and muscle/nerve biopsies. The duration of the initial progressive phase, the time from IVIg administration until the dogs were ambulating without assistance, and the duration of the complete episode were evaluated. Adverse reactions (anaphylaxis, mild hematuria) were observed in two dogs. Dogs treated with IVIg were ambulating without assistance after a median of 27.5 days (range, 15-127 days) from onset of clinical signs. The control group was ambulatory without assistance at a median of 75.5 days (range, 5-220 days). Even though this result is not statistically significant, there is a clear trend toward faster recovery in dogs treated with IVIg. 相似文献
63.
Gödecke T Yao P Napolitano JG Nikolić D Dietz BM Bolton JL van Breemen RB Farnsworth NR Chen SN Lankin DC Pauli GF 《Fitoterapia》2012,83(1):18-32
Despite numerous in vitro/vivo and phytochemical studies, the active constituents of Angelica sinensis (AS) have not been conclusively identified for the standardization to bioactive markers. Phytochemical analyses of AS extracts and fractions that demonstrate activity in a panel of in vitro bioassays, have repeatedly pointed to ligustilide as being (associated with) the active principle(s). Due to the chemical instability of ligustilide and related issues in GC/LC analyses, new methods capable of quantifying ligustilide in mixtures that do not rely on an identical reference standard are in high demand. This study demonstrates how NMR can satisfy the requirement for simultaneous, multi-target quantification and qualitative identification. First, the AS activity was concentrated into a single fraction by RP-solid-phase extraction, as confirmed by an alkaline phosphatase, (anti-)estrogenicity and cytotoxicity assay. Next, a quantitative 1H NMR (qHNMR) method was established and validated using standard compounds and comparing processing methods. Subsequent 1D/2D NMR and qHNMR analysis led to the identification and quantification of ligustilide and other minor components in the active fraction, and to the development of quality criteria for authentic AS preparations. The absolute and relative quantities of ligustilide, six minor alkyl phthalides, and groups of phenylpropanoids, polyynes, and poly-unsaturated fatty acids were measured by a combination of qHNMR and 2D COSY. The qNMR approach enables multi-target quality control of the bioactive fraction, and enables the integrated biological and chemical standardization of AS botanicals. This methodology can potentially be transferred to other botanicals with active principles that act synergistically, or that contain closely related and/or constituents, which have not been conclusively identified as the active principles. 相似文献
64.
Limited susceptibility of three different mouse (Mus musculus) lines to Porcine circovirus-2 infection and associated lesions
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Tanja Opriessnig Abby R. Patterson Douglas E. Jones Nicole M. Juhan Xiang-Jin Meng Patrick G. Halbur 《Canadian journal of veterinary research》2009,73(2):81-86
Porcine circovirus associated disease (PCVAD), a major global problem for pork producers, is characterized microscopically by depletion and histiocytic replacement of follicles in the lymphoid tissues. The objectives of this study were to determine 1) if Porcine circovirus-2 (PCV-2) inoculated mice (Mus musculus) can develop PCV-2 associated lymphoid lesions and serve as a model for PCVAD, and 2) if differences in PCV-2 host susceptibility exist among mice lines. Three groups (n = 48/group) of 4-wk-old male mice were used: BALB/c, C57BL/6, and C3H/HeJ. A 2 × 2 factorial analysis was designed for each group using PCV-2 inoculation and keyhole limpet hemocyanin in incomplete Freund’s adjuvant injections on day 0 and 7 as factors. Necropsies were performed on days 12, 17, 22, 27, 32, and 37. Serum samples collected at each necropsy tested negative for anti-IgG PCV-2 antibodies in all mice at all time points by 2 different PCV-2 enzyme-linked immunosorbent assays (ELISA). The PCV-2 DNA was detected by polymerase chain reaction (PCR) in 93% (100/108) of tissues and 42.6% (46/108) of serum samples from PCV-2-inoculated mice from days 12 to 37. Microscopic lesions consistent with PCV-2 infection were not observed in any mice and PCV-2 DNA and PCV-2 antigen were not detected in tissues by in-situ-hybridization or immunohistochemistry assays, respectively. Based on incidence of PCV-2 DNA in serum samples, the C57BL/6 mouse line was more resistant to PCV-2 infection than the other lines. The results indicate the mouse model likely has limited utility to advance understanding of the pathogenesis of PCV-2 associated lesions, but mice could potentially be important in the epidemiology of PCV-2. 相似文献
65.
Infectivity of porcine circovirus type 2 DNA in semen from experimentally-infected boars 总被引:1,自引:0,他引:1
Madson DM Ramamoorthy S Kuster C Pal N Meng XJ Halbur PG Opriessnig T 《Veterinary research》2009,40(1):10-Feb;40(1):10
Porcine circovirus type 2 (PCV2) is an economically important pathogen. It has been demonstrated that PCV2 DNA can be detected in boar semen by PCR; however, the biological relevance of this is unknown. The objectives of this study were to determine if semen positive for PCV2 DNA is infectious (1) in a swine bioassay, or (2) when used for artificial insemination. For the first objective, 4-week-old pigs were inoculated intraperitoneally with PCV2 DNA-negative (bioassay-control; n = 3), PCV2a DNA-positive (bioassay-PCV2a; n = 3), or PCV2b DNA-positive (bioassay-PCV2b; n = 3) raw semen, or PCV2 live virus (bioassay-positive; n = 3), respectively. Pigs inoculated with PCV2 DNA-positive semen and PCV2 live virus became viremic and developed anti-PCV2 antibodies indicating that the PCV2 DNA present in semen was infectious. For the second objective, three Landrace gilts were inseminated with PCV2 DNA-negative semen (gilts-controls) from experimentally-infected boars, and six gilts were artificially inseminated with semen positive for PCV2a DNA (gilts-PCV2a; n = 3) or PCV2b DNA (gilts-PCV2b; n = 3). Serum samples collected from the gilts in all groups remained negative for anti-PCV2 antibodies for the duration of the experiment. In addition, fetal serum samples from all 105-day-gestation fetuses were negative for anti-PCV2 antibodies or PCV2 DNA. Under the conditions of this study, PCV2 DNA-positive semen was not infectious when used to artificially inseminate gilts; however, it was demonstrated to be infectious in a swine bioassay model and therefore is a potential means of PCV2 transmission amongst swine herds. 相似文献
66.
PA Brown AS Khan R Draghia-Akli MA Pope AM Bodles-Brakhop DR Kern 《American journal of veterinary research》2012,73(9):1428-1434
Objective-To determine whether a novel optimized plasmid carrying the porcine growth hormone-releasing hormone (GHRH) wild-type cDNA administered at a lower dose was as effective at eliciting physiologic responses as a commercial GHRH plasmid approved for use in Australia. Animals-134 gilts. Procedures-Estrus was synchronized and gilts were bred. Pregnant gilts were assigned to 2 treatment groups (40 gilts/group) or 1 untreated control group (24 gilts). Gilts in one of the treatment groups received the commercial GHRH plasmid, whereas gilts in the other treatment group received a novel optimized GHRH plasmid; both plasmids were administered IM in the right hind limb, which was followed by electroporation. Sow and litter performance were monitored for the 3 gestations after treatment. Results-A significant increase in insulin-like growth factor-I concentrations, decrease in perinatal mortality rate, increase in the number of pigs born alive, and increase in the weight and number of pigs weaned were detected for both groups receiving the GHRH-expressing plasmids, compared with values for the control group. Additionally, there was a significant decrease in sow attrition in GHRH-treated females, compared with attrition in the control group, during the 3 gestations after treatment. Conclusions and Clinical Relevance-Both of the GHRH plasmids provided significant benefits for sow performance and baby pig survivability for pregnant and lactating sows and their offspring during the 3 gestations after treatment, compared with results for untreated control gilts. Use of a novel optimized plasmid reduced the effective plasmid dose in these large mammals. 相似文献
67.
Groesslinger K Tham T Egerbacher M Lorinson D 《Journal of the American Veterinary Medical Association》2005,226(3):383-386
OBJECTIVE: To determine prevalence and radiologic and histologic appearance of vesicourachal diverticula in dogs without clinical signs of urinary tract disease. DESIGN: Original study. ANIMALS: 50 dogs between 4 months and 17 years old representing 22 breeds that had been euthanatized for unrelated reasons; none of the dogs had a history or clinical signs of urinary tract disease. PROCEDURE: Retrograde positive-contrast radiography was performed, and radiographs were examined for macroscopic diverticula. Necropsy specimens from the urinary bladder vertex were examined by means of light microscopy for diverticula and signs of inflammation. RESULTS: 17 of the 50 (34%) dogs had vesicourachal diverticula, and 1 additional dog had a urachal cyst. Fifteen of the 17 diverticula were macroscopic; surface area of the diverticulum could be measured radiographically in 13 of these dogs and ranged from 1 to 90 mm2. The remaining 2 diverticula were microscopic. Sixteen diverticula were intramural and 1 was extramural. Light microscopic signs of bladder wall inflammation could be detected in 5 dogs, 4 of which had macroscopic diverticula. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that a high percentage of dogs without clinical signs of urinary tract disease may have vesicourachal [corrected] diverticula. Further studies are needed to determine the clinical relevance of vesicourethral diverticula in dogs. 相似文献
68.
A 5-month-old Morgan filly was presented to the Atlantic Veterinary College with a history of lethargy, fever, depression, anorexia, and dependent ventral edema. Diagnostic tests revealed severe inflammation, hypoproteinemia, and thickened small intestinal loops. Protein-losing enteropathy caused by Lawsonia intracellularis was diagnosed and treated successfully with erythromycin-rifampin. 相似文献
69.
Oral immunisation of wild boar against classical swine fever: concluding analysis of the recent field trials in Germany 总被引:6,自引:0,他引:6
Kaden V Heyne H Kiupel H Letz W Kern B Lemmer U Gossger K Rothe A Böhme H Tyrpe P 《Berliner und Münchener tier?rztliche Wochenschrift》2002,115(5-6):179-185
The recent oral immunisation trials in wild boar against classical swine fever (CSF) in Germany are described and evaluated in summary. After the first field study in Lower Saxony from 1993-1995 further immunisation trials started in Mecklenburg-Western Pomerania, Brandenburg, Lower Saxony, Baden-Württemberg and Saxony-Anhalt. The immunisation strategies and the size of the vaccination zones were different in the individual federal states. In principle, the bait vaccine based on the CSF virus strain "C" were laid out by hand. Later also the aerial distribution was carried out in selected areas of Mecklenburg-Western Pomerania. The application of baits by plane was introduced at the beginning of the immunisation measures in Saxony-Anhalt apart from the manual distribution. Up to now, the field trials show that the oral immunisation can be an additional tool for CSF control by increasing of herd immunity and reduction of the CSFV prevalence. However, the immunisation was not sufficient enough for young boars in the most field studies. Based on the evaluation of the immunisation experiments an improved immunisation procedure is recommended. 相似文献
70.
Aqueous misdirection and ciliary block (malignant) glaucoma after cataract removal in a llama 总被引:2,自引:1,他引:1
Ciliary block (malignant) glaucoma is caused by the posterior flow of aqueous humor into or behind the vitreous. It is a rare complication of anterior segment surgery in humans. This is a report of ciliary block glaucoma occurring as a postoperative complication of cataract surgery in a llama. Medical management was ineffective in lowering intraocular pressure (IOP). Posterior capsulotomy and anterior hyaloid disruption with a 22-gauge needle, in addition to medical management maintained IOP in the normal range until anterior vitrectomy could be performed. After vitrectomy, glaucoma resolved and medical treatment was no longer necessary. 相似文献