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51.
Lea Middendorf Marion Schmicke Kristian Düngelhoef Erwin Sieverding Heinrich Windhaus Dieter Mischok Dimitri Radko Christian Visscher 《Journal of animal physiology and animal nutrition》2021,105(Z2):70-78
The hepatic lipidosis (HL) in fattening turkeys is a disease has been known for a long time, but the cause and pathogenesis is still not clarified. A recent study reported unexplained high levels of iron in liver tissue of fattening turkeys suffering from HL. In this study, the iron status, possible infectious or inflammatory influences in form of an acute phase reaction and the analysis of fatty acid pattern in liver tissue of turkeys affected by HL were examined. Three cases of HL on three different fattening turkey farms were investigated during the outbreak of the disease. Clinically affected and non-affected animals were subjected to a pathological examination, where the diagnosis HL or non-affected was made. In total, 70 birds were examined (40 with HL, 30 without HL) and blood and liver samples were taken. Additionally, samples from 15 slaughtered birds were taken as a further control group. In liver tissue, the iron content and the content of long-chain fatty acids were determined; in blood samples, ferritin and transferrin were measured. The iron content in liver tissue was more than three times higher for animals with HL than among non-affected animals and the control group. The transferrin levels were lowest for animals with HL, highest in the control group and in between for non-affected animals. The fatty acid pattern in liver tissue of affected animals indicated a shift from polyunsaturated fatty acids to saturated fatty acids and monounsaturated fatty acids compared to the control group and the non-affected animals. Overall, the non-affected animals of a flock affected by HL were similar to the healthy animals of the abattoir. The low acute phase protein levels for animals with HL together with high iron contents could indicate a previous malnutrition/starvation period and/or severe liver damage for those animals suffering from HL. 相似文献
52.
Pradofloxacin is a new veterinary 8-cyano-fluoroquinolone developed for use against bacterial infections in dogs and cats involving both aerobic and anaerobic bacteria. The minimal bactericidal concentrations have been determined against clinical isolates of Staphylococcus pseudintermedius, Staphylococcus aureus, Escherichia coli, Pasteurella multocida, Streptococcus canis, Proteus spp., Fusobacterium spp., Porphyromonas gingivalis and Prevotella species. A subset of these species was selected, and the in vitro rate of kill by pradofloxacin was determined. For 27 of the 30 tested aerobic strains the pradofloxacin MBC was within two doubling dilutions of the MIC. For the remaining strains, the MIC and MBC were within three to four doubling dilutions. Pradofloxacin also demonstrated bactericidal activity against all anaerobic strains, and the MBC was equal to the MIC for four of the strains, within 1 doubling dilution for three strains, within 2 dilutions for a further 3 strains and within 3 dilutions for the remaining five strains. As pradofloxacin concentration was increased, a faster rate of killing was observed; bactericidal effects were seen in all cases at concentrations ≤ 0.25 μg/mL. The bactericidal activity against the anaerobic strains was marked, of particular relevance was the complete absence of regrowth even at 48 h at concentrations as low as 0.125 μg/mL. In conclusion, pradofloxacin exhibits clear bactericidal activity in terms of MBC and kill kinetics against aerobic and anaerobic clinical isolates from dogs and cats at concentrations that are greatly exceeded within the systemic circulation after administration of the recommended therapeutic doses to the target animals. It is expected that such a rapid rate of kill will play a significant role in clinical efficacy. These data demonstrate the complete and rapid killing of anaerobic bacteria by a veterinary 8-cyano-fluoroquinolone. 相似文献
53.
Meyer C 《Science (New York, N.Y.)》1985,227(4693):1421-1428
The ores of chromite, nickel, copper, and zinc show a wide distribution over geologic time, but those of iron, titanium, lead, uranium, gold, silver, molybdenum, tungsten, and tin are more restricted. Many of the limitations to specific time intervals are probably imposed by the evolving tectonic history of Earth interacting with the effects of the biomass on the evolution of the earth's s surface chemistry. Photosynthetic generation of free oxygen and "carbon" contributes significantlly to the diversity of redox potentials in both sedimentary and igneous-related processes of ore formation, influencing the selection of metals at the source, during transport, and at the site of ore deposition. 相似文献
54.
Winfried Schröder Stefan Nickel Simon Schönrock Roman Schmalfuß Werner Wosniok Michaela Meyer Harry Harmens Marina V. Frontasyeva Renate Alber Julia Aleksiayenak Lambe Barandovski Oleg Blum Alejo Carballeira Maria Dam Helena Danielsson Ludwig De Temmermann Anatoly M. Dunaev Barbara Godzik Katrin Hoydal Zvonka Jeran Gunilla Pihl Karlsson Pranvera Lazo Sebastien Leblond Jussi Lindroos Siiri Liiv Sigurður H. Magnússon Blanka Mankovska Encarnación Núñez-Olivera Juha Piispanen Jarmo Poikolainen Ion V. Popescu Flora Qarri Jesus Miguel Santamaria Mitja Skudnik Zdravko Špirić Trajce Stafilov Eiliv Steinnes Claudia Stihi Ivan Suchara Lotti Thöni Hilde Thelle Uggerud Harald G. Zechmeister 《Annals of Forest Science》2017,74(2):31
Key message
Moss surveys provide spatially dense data on environmental concentrations of heavy metals and nitrogen which, together with other biomonitoring and modelling data, can be used for indicating deposition to terrestrial ecosystems and related effects across time and areas of different spatial extension.Context
For enhancing the spatial resolution of measuring and mapping atmospheric deposition by technical devices and by modelling, moss is used complementarily as bio-monitor.Aims
This paper investigated whether nitrogen and heavy metal concentrations derived by biomonitoring of atmospheric deposition are statistically meaningful in terms of compliance with minimum sample size across several spatial levels (objective 1), whether this is also true in terms of geostatistical criteria such as spatial auto-correlation and, by this, estimated values for unsampled locations (objective 2) and whether moss indicates atmospheric deposition in a similar way as modelled deposition, tree foliage and natural surface soil at the European and country level, and whether they indicate site-specific variance due to canopy drip (objective 3).Methods
Data from modelling and biomonitoring atmospheric deposition were statistically analysed by means of minimum sample size calculation, by geostatistics as well as by bivariate correlation analyses and by multivariate correlation analyses using the Classification and Regression Tree approach and the Random Forests method.Results
It was found that the compliance of measurements with the minimum sample size varies by spatial scale and element measured. For unsampled locations, estimation could be derived. Statistically significant correlations between concentrations of heavy metals and nitrogen in moss and modelled atmospheric deposition, and concentrations in leaves, needles and soil were found. Significant influence of canopy drip on nitrogen concentration in moss was proven.Conclusion
Moss surveys should complement modelled atmospheric deposition data as well as other biomonitoring approaches and offer a great potential for various terrestrial monitoring programmes dealing with exposure and effects.55.
Change of shear resistance and compressibility of Ap-horizon material from loess-derived Parabraunerde Standardized artificial bodies prepared from soil material of a loessderived parabraunerde-Ap-horizon were tested with respect to their shear resistance and compressibility. The noncalcareous material was enriched with lime (2 stepts), soil humidity changed (3 steps) and the normal pressure increased (4 steps). Liming generally caused an increased initial shear resistance and led to a lowering of compressibility. The effect of lime is interpreted as an result of flocculation of the clay particles at the points of contact between silt grains in the soil matrix. The problems of transferring those results to the field are discussed. 相似文献
56.
Factors affecting urine reagent strip blood results in dogs and nonhuman primates and interpretation of urinalysis in preclinical toxicology studies: a Multi‐Institution Contract Research Organization and BioPharmaceutical Company Perspective 下载免费PDF全文
57.
Iahtasham Khan Lothar H. Wieler Mahboob Ahmad Butt Mandy C. Elschner Ashiq Hussain Cheema Lisa D. Sprague Heinrich Neubauer 《Journal of Equine Veterinary Science》2012
Glanders is a highly infectious and zoonotic disease of solipeds caused by Burkholderia mallei. Progressive loss of efficiency and fatal outcome resulted in massive economic losses, which forced veterinary authorities throughout the world to implement disease control measures; these measures included mass testing using the complement fixation test and/or malleinization, and the culling of positives. This led to the eradication of glanders from Western Europe and North America in the 1950s. However, in the last decade, the number of outbreaks in Asia and South America increased steadily, and glanders regained the status of a re-emerging transboundary disease. Pakistan has been an endemic country for the past 120 years, but concise data on the presence of disease are not available. A total of 533 serum samples were collected from draught equines, a suspected risk group for glanders, from various districts of Punjab in Pakistan. The complement fixation test and the highly sensitive Western blot technique were used for serodiagnosis. No animal (horse, mule, and donkey) was found to be positive for infection. Glanders seems to be restricted to remote, sporadic pockets of endemicity and may cause outbreaks after being introduced into naive populations by (asymptomatic) shedders. 相似文献
58.
Luke Randall Katharina Heinrich Robert Horton Lucy Brunton Matthew Sharman Victoria Bailey-Horne Meenaxi Sharma Ian McLaren Nick Coldham Chris Teale Jeff Jones 《Research in veterinary science》2014
Waste milk samples from 103 farms in England and Wales were examined for the presence of β-lactam antibiotics and ESBL-producing Enterobacteriaceae. Approximately 10 months after the initial sampling, further waste milk, environmental and faecal samples from farms shown to be positive for CTX-M Escherichia coli were investigated further. Isolates with an ESBL phenotype were tested by PCR for the presence of blaCTX-M, blaOXA, blaSHV and blaTEM genes. Isolates positive for blaCTX-M were sequenced to determine CTX-M type. Representative isolates were further examined by PFGE, plasmid replicon typing and serotyping. Of particular interest, 21.4% of waste milk samples contained residues of the cephalosporin cefquinome, which was significantly associated with CTX-M bacteria. Such bacteria occurred in 5.8% of the waste milk samples (including 3.9% CTX-M E. coli). CTX-M types identified were 1, 14, 14b and 15, but none of the E. coli were serotype O25, the serotype of the human pandemic strain. 相似文献
59.
Dueger EL George LW Angelos JA Tankersley NS Luiz KM Meyer JA Portis ES Lucas MJ 《American journal of veterinary research》2004,65(9):1185-1188
OBJECTIVE: To evaluate the efficacy of ceftiofur crystalline-free acid (CCFA) administered into the posterior aspect of an ear for treatment of corneal ulceration associated with naturally occurring infectious bovine keratoconjunctivitis (IBK). ANIMALS: 78 beef calves located at Sierra Foothills Field Station (SFS) and 52 calves located at a commercial dairy (CD). All calves were from 3 to 9 months old. PROCEDURE: At each site, calves were randomly allocated to 1 of 2 treatment groups by use of a block design determined by corneal ulcer size. A single dose of CCFA (6.6 mg of ceftiofur equivalents/kg, s.c.) was administered into the posterior aspect of a pinna. A second group of calves received a single dose of vehicle (0.03 mL/kg, s.c.; controls). Corneal ulcers were photographed, and clinical signs were assessed in calves every 3 to 4 days for 21 days. RESULTS: A positive treatment effect was detected at SFS. Results at the CD were inconclusive because ulcer healing occurred rapidly in control and CCFA-treated calves. At SFS, treatment with CCFA resulted in shorter mean healing times, smaller corneal ulcer surface area measurements, amelioration of ocular discharge and photophobia, and a 50% increase in the percentage of calves healed by day 14. After adjustment for initial corneal ulcer size, treatment with CCFA resulted in a 4-fold increase in the odds of corneal ulcer healing by day 14, compared with controls. CONCLUSIONS AND CLINICAL RELEVANCE: A single dose of CCFA administered into the posterior aspect of a pinna had a positive treatment effect against naturally occurring IBK in calves with corneal ulcerations. 相似文献
60.
Wardatou Boukari Denis Filloux Jean Heinrich Daugrois Emmanuel Fernandez Dimitre Mollov Claudia Kaye Martha Hincapie Alexander Sanchez Jianping Wang Philippe Roumagnac Philippe Rott 《Plant pathology》2020,69(6):1060-1069
Viruses in the genus Mastrevirus (family Geminiviridae), including those infecting sugarcane, have natural geographical ranges almost exclusively restricted to Africa and the Indian Ocean islands off the African coast. Only sugarcane white streak virus (SWSV) in Barbados and sugarcane striate virus (SStrV) in Florida and Guadeloupe are known to infect a few sugarcane varieties in the Western Hemisphere. In this study, PCR assays were developed to detect these two viruses in sugarcane. Five hundred and seventy-one DNA samples from Saccharum species and interspecific hybrids from the Miami World Collection of sugarcane and related grasses were tested for the presence of SStrV and SWSV by PCR. No variety was found infected by SWSV but SStrV was detected in 19 varieties. PCR data were confirmed by sequencing amplified fragments (248 bp). These fragments shared 93%–100% nucleotide identity with SStrV sequences from the GenBank database. SStrV isolates were distributed in six phylogenetic groups, including the four strains of the virus. Most varieties infected by SStrV originated from Asia, thus confirming a previous hypothesis stating that this virus originated from this continent. Absence of SStrV in commercial sugarcane in Florida also suggested that this virus has not been spread in this location, while infected plants have been present for several decades. 相似文献