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81.
A 36-day-old, 100-kg Thoroughbred colt was presented with a sudden onset of abnormal head carriage and pyrexia. Radiography revealed an osteomyelitis of the vertebral body of the second cervical vertebra. Ultrasonography revealed abscessation in the region of the atlantoaxial articulation on the left side, and fluid aspirated from the abscess confirmed suppurative inflammation. Surgical management was not feasible on economic grounds, and therefore this case was managed with aggressive medical therapy based on the most likely pathogens involved. To provide prolonged antibiotic therapy within the client’s budget, the antibiotic flucloxacillin (Staphlex, 500 mg) was used at a dose of 10 mg/kg by mouth, three times daily. Thirty-eight days after first presentation, the foal was euthanized because of chronic pain and deterioration in neurologic signs. A diagnosis of chronic osteomyelitis of the body of the second cervical vertebra (axis) was made with concurrent septic arthritis of the atlantoaxial joint involving the articular surface of the first cervical vertebra (atlas) and cervical myelopathy of the spinal cord within the first two vertebrae. No pathogens were isolated post mortem. This is the first report to describe the use of flucloxacillin in a foal. Although the outcome was fatal, the medical therapy provided could be considered successful at sterilizing the bony lesion. 相似文献
82.
Thomas H. Suchanek Janis Cooke Kaylene Keller Salvador Jorgensen Peter J. Richerson Collin A. Eagles-Smith E. James Harner David P. Adam 《Water, air, and soil pollution》2009,196(1-4):51-73
The Sulphur Bank Mercury Mine (SBMM), active intermittently from 1873–1957 and now a USEPA Superfund site, was previously estimated to have contributed at least 100 metric tons (105 kg) of mercury (Hg) into the Clear Lake aquatic ecosystem. We have confirmed this minimum estimate. To better quantify the contribution of the mine in relation to other sources of Hg loading into Clear Lake and provide data that might help reduce that loading, we analyzed Inputs and Outputs of Hg to Clear Lake and Storage of Hg in lakebed sediments using a mass balance approach. We evaluated Inputs from (1) wet and dry atmospheric deposition from both global/regional and local sources, (2) watershed tributaries, (3) groundwater inflows, (4) lakebed springs and (5) the mine. Outputs were quantified from (1) efflux (volatilization) of Hg from the lake surface to the atmosphere, (2) municipal and agricultural water diversions, (3) losses from out-flowing drainage of Cache Creek that feeds into the California Central Valley and (4) biotic Hg removal by humans and wildlife. Storage estimates include (1) sediment burial from historic and prehistoric periods (over the past 150–3,000 years) from sediment cores to ca. 2.5m depth dated using dichloro diphenyl dichloroethane (DDD), 210Pb and 14C and (2) recent Hg deposition in surficial sediments. Surficial sediments collected in October 2003 (11 years after mine site remediation) indicate no reduction (but a possible increase) in sediment Hg concentrations over that time and suggest that remediation has not significantly reduced overall Hg loading to the lake. Currently, the mine is believed to contribute ca. 322–331 kg of Hg annually to Clear Lake, which represents ca. 86–99% of the total Hg loading to the lake. We estimate that natural sedimentation would cover the existing contaminated sediments within ca. 150–300 years. 相似文献
83.
Lyophilisates of the ascomycetes Penicillium solitum and Aspergillus niger converted alpha-farnesene to 7-hydroxyfarnesene as the major product. The radical mechanism of this bioconversion was proven by electron spin resonance (ESR) and GC-MS using the spin trapping technique. Intermediate carbon-centered radicals of alpha-farnesene were captured using two spin traps, 2-methyl-2-nitrosopropane and alpha-(4-pyridyl-1-oxide)- N- tert-butylnitrone, respectively. The evaluation of the coupling constants and hyperfine couplings of the ESR spectra showed that tertiary carbon radicals were trapped. The radical position at C7 of alpha-farnesene was derived from EI and CI mass spectra of the corresponding MNP spin adduct. The present study demonstrates that the complementary application of ESR and MS spectrometric data allows the detailed evaluation of a radical mechanism of a fungal terpene transformation reaction. 相似文献
84.
Frederiksen AM Lund MN Andersen ML Skibsted LH 《Journal of agricultural and food chemistry》2008,56(9):3297-3304
Oxidation of the myofibrillar muscle protein myosin from pork by hypervalent myoglobin species (MbFe(III)/H 2O2 radical generating system) was investigated in aqueous solution in the pH range of 5.0-7.8 by electron spin resonance (ESR) spectroscopy using N- tert-butyl-alpha-phenylnitrone (PBN) as spin trap and indirectly by determination of the rate of reduction of hypervalent myoglobin species by UV spectroscopy. Cross-linking of myosin was examined by SDS-PAGE. The target for oxidative modification of myosin was studied by thiol blocking by N-acetylmaleimide (NEM) and by determining oxidative modification of myosin thiols. The reaction between myosin and hypervalent myoglobin was fast and showed little dependence on pH. The myosin radicals formed were observed to be short-lived. Myosin thiols are suggested to be the main target for oxidative modification, as NEM-treated myosin did not form radicals in the presence of hypervalent myoglobin. A significant decrease in thiol content was already demonstrated 25 s after initiation of oxidation of myosin. The majority of myosin heavy chain (MHC) was demonstrated to be cross-linked through intermolecular disulfide bonding 1 h after initiation of oxidation. This demonstrates that thiols are important for radical formation and cross-linking of myosin during oxidation with hypervalent myoglobin at the pH of meat products. 相似文献
85.
86.
The basic assumptions for applying superovulation and embryo transplantation to breeding plans are discussed.In a model simulation the superovulation—egg transfer technique was applied to elite cows (dams of bulls) in the breeding plan of a 500 000 cow population. The number of sons obtained per elite cow per year was varied from 0.5 (basis) to 10.0.The increase in genetic gain amounted to a maximum of 0.22 percentage units (from 1.51 to 1.73) per year and the extra returns to 44 000 D.Kr. per bull calf recruited, when the only factor allowed to change was the number of sons per elite cow.For all alternatives examined the optimum plan is also shown. In this case the maximum extra returns per bull calf recruited will be about 54 000 D.Kr., that is 10 000 D.Kr. more than in the basic plan.The results indicate that the utilization of a combined superovulation—egg transfer procedure might prove profitable when based on an efficient selection of dams of bulls. 相似文献
87.
88.
The objective of this study was to examine how increased feed intake of the sow during early to mid-gestation affects sow performance and the muscle fiber number, performance, and technological meat quality of the offspring. Thirty-nine pregnant sows (Landrace x Large White sows mated to Landrace or Large White boars) in their fourth parity were assigned to one of three treatments: 1) the sows were either fed restrictively (control = 15 MJ of NE/d from d 1 to 90, then 24 MJ of NE/d from d 91 to 112, and again 15 MJ of NE/d from d 113 to 115 of gestation); 2) fed ad libitum from d 25 to 50 (A25-50); or 3) ad libitum from d 25 to 70 (A25-70) and as control in the remaining periods. The offspring were weaned at 4 wk of age and had free access to feed from 2 wk of age until slaughter. They were slaughtered litterwise at an average body weight of 104 +/- 14 kg. Estimates for total, primary (P-), and secondary (S-) muscle fiber number; muscle fiber area; and DNA and RNA content were analyzed in semitendinosus muscle (ST) samples from the heaviest, middle, and lightest weight (LW) pigs of each sex within litter selected at slaughter. Technological meat quality traits (pH at 24 h postmortem, drip loss, Minolta color, and pigment) were analyzed in longissimus dorsi muscle. Fiber number, fiber area, and concentrations and content of DNA and RNA of the offspring were not significantly affected by increased maternal nutrition. The ST muscle weight was lower in offspring from A25-50 than control sows (P = 0.019). Average daily gain, carcass weight, and the muscle deposition rate also were numerically lower for A25-50 than control and A25-70 pigs. An interaction between treatment and pig weight was found for muscle deposition rate (P = 0.006), in that LW pigs from treatment A25-50 had a lower deposition rate than LW pigs from control. We found no effect of treatment on the meat quality traits in the offspring. Also, barrows had a higher (P < 0.05) number of P-fibers, higher daily gain, and carcass weight than female pigs. No differences were found on any meat quality traits between sexes. Thus, ad libitum feeding of pregnant sows from d 25 to 50 or d 25 to 70 of gestation did not have any beneficial effect on muscle fiber number and area in the offspring. It seems that maternal ad libitum feeding from d 25 to 50 in gestation had a negative effect on postnatal muscle growth, with especially the LW pigs being affected. 相似文献
89.
J B Jorgensen 《Nordisk veterinaermedicin》1977,29(6):267-270
Cattle and swine slurry and a mixture of equal parts of both, was mixed with a culture of M. paratuberculosis, 0.1 mg per ml (1 mg = 33 X 10(6) viable units) and stored under anaerobic conditions at 5 degrees and 15 degrees C. At 5 degrees C the survival time for M. paratuberculosis was 252 days in all 3 kinds of slurry, and at 15 degrees C it was 98 days in cattle slurry, 182 days in swine slurry, and 168 days in mixed slurry. 相似文献
90.