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91.
Berge AC Sischo WM Craigmill AL 《Journal of the American Veterinary Medical Association》2006,229(8):1279-1281
OBJECTIVE: To determine the antimicrobial susceptibility of common respiratory tract pathogens from sheep and goats. DESIGN: Cross-sectional study. SAMPLE POPULATION: 41 respiratory tract isolates from sheep and 36 isolates from goats. PROCEDURES: Disk diffusion assay was used to determine antimicrobial susceptibility of isolates to amoxicillin-clavulanic acid, ceftiofur, ciprofloxacin, florfenicol, and tetracycline. Minimum inhibitory concentrations of florfenicol for these isolates were determined by use of the microbroth dilution technique. RESULTS: The most common isolates were Pasteurella multocida (n = 28) and Mannheimia haemolytica (39). All isolates were susceptible to amoxicillin-clavulanic acid, ceftiofur, ciprofloxacin, and florfenicol. Five percent (4/77) of isolates were resistant to tetracycline. CONCLUSIONS AND CLINICAL RELEVANCE: Susceptibility of respiratory tract pathogens isolated from sheep and goats to commonly used antimicrobial drugs in this study was high. Treatment of these species for bacterial respiratory tract disease is likely not complicated by antimicrobial resistance. 相似文献
92.
C Pöhlker KT Wiedemann B Sinha M Shiraiwa SS Gunthe M Smith H Su P Artaxo Q Chen Y Cheng W Elbert MK Gilles AL Kilcoyne RC Moffet M Weigand ST Martin U Pöschl MO Andreae 《Science (New York, N.Y.)》2012,337(6098):1075-1078
The fine particles serving as cloud condensation nuclei in pristine Amazonian rainforest air consist mostly of secondary organic aerosol. Their origin is enigmatic, however, because new particle formation in the atmosphere is not observed. Here, we show that the growth of organic aerosol particles can be initiated by potassium-salt-rich particles emitted by biota in the rainforest. These particles act as seeds for the condensation of low- or semi-volatile organic compounds from the atmospheric gas phase or multiphase oxidation of isoprene and terpenes. Our findings suggest that the primary emission of biogenic salt particles directly influences the number concentration of cloud condensation nuclei and affects the microphysics of cloud formation and precipitation over the rainforest. 相似文献
93.
BACKGROUND: Non-repellent insecticides, including fipronil and indoxacarb, are becoming increasingly important for soil treatments to manage the eastern subterranean termite, Reticulitermes flavipes (Kollar). The effects of these insecticides on termite walking and tunneling behavior could significantly reduce their efficacy against colonies. RESULTS: Groups of R. flavipes were exposed to several concentrations of commercial formulations of fipronil and indoxacarb, and the ability of treated termites to tunnel in soil and walk was assessed. Increasing insecticide concentration resulted in a reduction in the ability of R. flavipes to walk, tunnel and form tunnel branches; the importance of these effects on the use of non-repellent insecticides is discussed. CONCLUSION: Exposure of R. flavipes to 1, 10 or 50 mg L−1 of fipronil or 50, 100 or 200 mg L−1 of indoxacarb significantly reduced termite walking and tunneling and the number of tunnel branches. Distance walked (ca 73 mm) by untreated control termites did not change over time for at least 16 h after treatment; control termites formed ca 150 cm of tunnels with ca 40 branches. Copyright © 2012 Society of Chemical Industry 相似文献
94.
Frank H. Arthur 《Journal of pest science》2013,86(3):507-513
A series of experiments were conducted to evaluate residual efficacy of the insecticidal pyrrolle chlorfenapyr (Phantom®) on treated concrete for control of Tribolium castaneum (Herbst), assess development of progeny from exposed parental adults, and to determine if starvation before exposure with or without a flour food source increased susceptibility of adult T. castaneum and adult Tribolium confusum Jacqueline du Val to chlorfenapyr. No adults survived exposure on concrete treated with chlorfenapyr at the maximum label rate of 1.1 g active ingredient (AI)/m2, and no progeny were produced in bioassays conducted at 0–8 weeks posttreatment. In the second test, application rates were reduced, and bioassays were conducted at 27 and 32 °C. Adult survival and progeny production decreased as the application rate increased from 28 to 225 mg AI/m2, and survival and progeny production were generally lower at 32 °C than at 27 °C, but at higher rates survival was <1 %, and no progeny were produced. In the final test, adult T. castaneum and adult T. confusum were starved for 1–7 days and then exposed either with or without flour on concrete treated with 3.9 and 27.5 mg AI chlorfenapyr/m2. Mortality generally increased with starvation time, the presence of a food source led to decreased mortality at both application rates, and T. confusum was the more susceptible of the two species. Results show that chlorfenapyr could effectively control both species, but precise dosage levels need to be determined. Also, the presence of a food source greatly compromises adult control. 相似文献
95.
Wei Jiang Panpan Ye Chen-Tung Arthur Chen Kuiwu Wang Pengyuan Liu Shan He Xiaodan Wu Lishe Gan Ying Ye Bin Wu 《Marine drugs》2013,11(12):4761-4772
Two novel cyclodepsipeptides containing an unusual anthranilic acid dimer and a d-phenyllactic acid residues, clavatustides A (1) and B (2), were identified from cultured mycelia and broth of Aspergillus clavatus C2WU isolated from Xenograpsus testudinatus, which lives at extreme, toxic habitat around the sulphur-rich hydrothermal vents in Taiwan Kueishantao. This is the first example of cyclopeptides containing an anthranilic acid dimer in natural products, and the first report of microbial secondary metabolites from the hydrothermal vent crab. Clavatustides A (1) and B (2) suppressed the proliferation of hepatocellular carcinoma (HCC) cell lines (HepG2, SMMC-7721 and Bel-7402) in a dose-dependent manner, and induced an accumulation of HepG2 cells in G1 phase and reduction of cells in S phase. 相似文献
96.
Abstract Extract Recently, we reported on outbreaks of Leptospira interrogans serovar pomona infection in newly weaned lambs(1). It was suggested that wet environmental conditions played an important role in the pathogenesis of the disease in that class of sheep. This communication presents observations on another case of ovine leptospirosis, one that occurred under different circumstances, i.e. different season, age and environmental conditions. 相似文献
97.
Extract Several indicators of thrombosis and thrombolysis were measured in four groups of 16 pigs fed for 10 weeks on either a low fat basal ration or rations containing 10% anhydrous milkfat (AMF), 10% fish oil (MaxEPA), or 10% hydrogenated coconut oil (HCO). At the end of the feeding period, pigs on the three test fat/oil rations were subjected to balloon angioplasty of both femoral arteries. Thrombus size at the site of injury was measured both morphometrically and using autologous blood platelets labelled with 99Tc-HMPAO (technetium - “Deretec”). 相似文献
98.
Fiona Maunsell G Arthur Donovan 《Veterinary Clinics of North America: Food Animal Practice》2008,24(1):155-190
Biosecurity, biocontainment, and disease risk management on dairy replacement operations are time- and labor-intensive, planned programs. Oftentimes the value of these programs is realized only after disease is introduced to a facility or a disease outbreak occurs. There is no "one-plan-fits-all;" each plan must be tailored to meet the needs of management's goals and expectations and problems specific to a production enterprise or geographic region. A standard framework applicable to biosecurity programs includes: (1) hazard identification, (2) exposure assessment, (3) risk characterization, and (4) risk management. The discussion presented here helps lay the framework for development and implementation of biosecurity and risk-management programs within dairy replacement facilities. 相似文献
99.
Tivers MS Catchpole B Gregory SP House AK 《Veterinary immunology and immunopathology》2008,125(1-2):31-36
German Shepherd Dogs have an increased incidence of anal furunculosis (AF), which is a disease characterised by inflammation and ulceration of the perianal tissues. Ciclosporin, an immunosuppressive drug, has been successfully used to treat AF, suggesting that the pathogenesis of disease is likely to have an immune-mediated component. Previous research has shown that the cytokine mRNA profile in AF lesions is consistent with T cell-mediated inflammation. The aims of the current study were to quantify IL-2 and IFNgamma mRNA expression in AF biopsies taken before and after treatment with ciclosporin and to compare cytokine expression with lesion severity. Twenty-two dogs with AF were recruited into the study and lesional biopsies were taken prior to ciclosporin therapy. Lesion severity was graded using a visual analogue scale. All dogs were evaluated after 4 weeks of ciclosporin therapy and, in 10 dogs with persistent disease, residual lesions were resected. RNA was extracted from AF-lesional tissue and control perianal tissue samples (n=10), which was used as the template for RT-PCR. Analysis of IL-2 and IFNgamma mRNA expression was performed using real-time PCR. IL-2 and IFNgamma mRNA was consistently detected in pre-treatment AF biopsies and, when quantified, this was significantly increased compared to control tissue (P<0.05). However, no correlation was seen between lesion severity and pre-treatment cytokine mRNA expression. In the ten paired pre- and post-treatment samples, IL-2 mRNA expression was significantly reduced in residual disease tissue following ciclosporin therapy (P=0.013). Treatment with ciclosporin seemed to result in decreased expression of IFNgamma mRNA in AF lesions but this was not statistically significant. In six of the 10 dogs with persistent disease, T cell cytokine mRNA could still be detected in the tissues, suggesting that there was inadequate immunosuppression. The absence of a correlation between T cell cytokine expression and the severity of disease suggests that tissue destruction observed in AF might be a consequence of other inflammatory mediators or downstream effects of T cell activation. 相似文献
100.
Gooneratne SR Eason CT Milne L Arthur DG Cook C Wickstrom M 《The Onderstepoort journal of veterinary research》2008,75(2):127-139
Acute and long-term effects of a single, relatively high oral dose (0.25 and 0.30 mg/kg) of sodium monofluoroacetate (1080) on the survival and productivity of sheep were evaluated to establish a better understanding of 1080 poisoning and identify more specific changes diagnostic of toxicosis. In survivors, clinical signs of acute 1080 toxicosis such as salivation and lethargy were generally very mild. Fasted animals were more prone to 1080 toxicity. In animals that died, more severe signs, including tachypnoea, dyspnoea, and tremors occurred for 15-20 min prior to death. 1080 concentrations were highest in the blood > heart > skeletal muscle > liver. 1080 could not be detected in any of these organs of the animals that survived. Serum citrate concentrations were elevated for 4 days after dosing. No clinical or biochemical abnormalities were found in any animal after 4 days. Histopathological lesions were most marked in the heart and lung with inflammation, necrosis, and scattered foci of fibrous tissue in the myocardium, pulmonary oedema and inflammation of the lung. No adverse long-term effects on general health or reproductive performance were observed in any sheep that survived the first 4 days following exposure to 1080. The most reliable diagnostic indicators of 1080 exposure in sheep were measurement of its residues in blood, skeletal muscle and ruminal contents, increased serum citrate concentration, elevated heart rate, and characteristic electrocardiograph changes (up to 4 days after exposure). Death from 1080 is most likely to occur within 96 h, and animals that survived this period appeared normal. 相似文献