Sustainable control of nematodes in ruminants     

Stafford K  Morgan E  Coles G 《The Veterinary record》2006,159(18):607

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The stress caused by laparoscopy in sheep and its alleviation     

Stafford KJ  Chambers JP  Sylvester SP  Kenyon PR  Morris ST  Lizarraga I  de Nicolo G 《New Zealand veterinary journal》2006,54(3):109-113

AIM: To determine the plasma cortisol response to laparoscopy in ewes and investigate means of reducing it. METHODS: Ewes without lambs at foot (n=40) were subjected to one of three control or one laparoscopy treatments (n=10 ewes/treatment), being: no restraint or drugs; acepromazine maleate (ACP) control and no restraint; ACP and restraint in a cradle for 5 min; and laparoscopy following ACP. Additional ewes with lambs at foot (n=30) were subjected to: laparoscopy following ACP; laparoscopy following ACP and ketoprofen; and laparoscopy following detomidine. Drugs were injected 20 min before treatment, after a first blood sample had been taken. Blood samples were taken by jugular venepuncture from the ewes 20 min before treatment and at 20, 40, 60, 90, 120, 150 and 180 min after treatment, while all ewes were held in a pen. Plasma was harvested and assayed for its concentration of cortisol. RESULTS: Plasma cortisol concentrations (PCC) remained constant in ewes in the control restraint group for 80 min. In ewes given ACP, PCC increased for the first 20 min after treatment but then returned to pre-treatment concentrations. PCC of ewes given ACP and restrained in a cradle were elevated above pre-treatment concentrations for 90 min. PCC in ewes subjected to laparoscopy following sedation with ACP increased to a peak at 40 min and returned to pre-treatment concentrations after 60 (with lambs) or 120 (without lambs) min. When ACP and ketoprofen were given before laparoscopy, PCC peaked at 20 min and returned to pre-treatment concentrations by 40 min. PCC of ewes given detomidine before laparoscopy remained at pre-treatment concentrations throughout. PCC of ewes subjected to laparoscopy with ACP sedation only were greater than those of control restraint, ACP control, and ewes subjected to laparoscopy after being given ketoprofen or detomidine between 20 and 60 min after treatment. PCC of ewes subjected to laparoscopy were greater than those of control ewes placed in a cradle at 20 and 40 min. PCC of ewes given ketoprofen were lower than those of ewes subject to laparoscopy following ACP. CONCLUSIONS: Laparoscopy, even after sedation with ACP, caused some distress in ewes, as evidenced by increased plasma cortisol levels. Plasma cortisol response was alleviated by the administration of ketoprofen and eliminated by detomidine, probably because of both analgesic and sedative effects of the latter drug.  相似文献   

Effects of age on the electroencephalographic response to castration in lambs anaesthetized with halothane in oxygen from birth to 6 weeks old     

Craig B Johnson BVSc  PhD  DVA  Diplomate ECVA    Shauna P Sylvester BSc  MSc    Kevin J Stafford MVB  MSc  PhD    Sheryl L Mitchinson BSc    R Neil Ward  & David J Mellor† BSc  PhD  HonAssocRCVS 《Veterinary anaesthesia and analgesia》2009,36(3):273-279

ObjectivesTo characterize changes in the cerebro‐cortical response of lambs to rubber‐ring castration during the first 6 weeks of postnatal life.AnimalsCoopworth‐Texel cross ram lambs between 3 hours and 44 days of age.MethodsThe electroencephalogram (EEG) and heart rate responses to rubber ring castration were compared. Anaesthesia was induced via a face mask and maintained with halothane in oxygen (e′_Hal = 1.2%). Once a stable plane of anaesthesia had been achieved, data collection of EEG and electrocardiogram (ECG) commenced, and the lambs were castrated 15 minutes later, using rubber rings. Heart rate was derived from the ECG and the median frequency (F₅₀), spectral edge frequency (F₉₅) and total power (p_tot) were derived from the EEG.ResultsCastration‐induced changes in F₅₀ increased from 2 ± 1.8% in the youngest lambs to a maximum of 33 ± 8.9% in the 36 ± 0.5 day‐old lambs. Changes in F₉₅ increased from ?7 ± 3% in the youngest lambs to a maximum of 16 ± 11% in the 36 ± 0.5 day‐old lambs. Linear regression analysis in lambs up to 10 days of age demonstrated a change in the response with age that was significantly different from zero for F₅₀ (r² = 0.28, p = 0.007) and F₉₅ (r² = 0.38, p = 0.001), but not for p_tot or heart rate.ConclusionThis study identified significant changes in the responsiveness of the lambs’ cerebral cortex to the noxious stimulation of castration over the first 7–10 days of postnatal life. The results suggest that mechanisms that suppress responses of the fetus to noxious stimulation may still be active in the first few days after birth.Clinical relevanceThis study documents changes in central nociceptive processing which may reflect the ability of neonatal animals to perceive pain.  相似文献   

Metabolism of 2-chloro-N-isopropylacetanilide (propachlor) in the leaves of corn, sorghum, sugarcane, and barley   总被引：1，自引：0，他引：1  

G L Lamoureux  L E Stafford  F S Tanaka 《Journal of agricultural and food chemistry》1971,19(2):346-350

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Effect of rate on soil shear strength and soil-metal friction I. Shear strength     

J.V. Stafford  D.W. Tanner 《Soil & Tillage Research》1983,3(3):245-260

The effect of deformation rate on the shear strength of a sandy and a clay soil has been examined in a new laboratory rig designed to shear soil in the range equivalent to 0.0015-5 m/s sliding speed. Soil cohesion was found to vary logarithmically with deformation rate over a wide range of moisture contents. The soil internal friction angle was independent of deformation rate and the residual shear strength did not vary in a consistent manner with deformation rate. The results have important bearing on the efficiency of soil working operations such as cultivation, earth moving and traction.  相似文献   

Atrazine metabolism in sorghum: chloroform-soluble intermediates in the N-dealkylation and glutathione conjugation pathways   总被引：2，自引：0，他引：2  

R H Shimabukuro  W C Walsh  G L Lamoureux  L E Stafford 《Journal of agricultural and food chemistry》1973,21(6):1031-1036

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Combined extraction-cleanup column chromatographic procedure for determination of dicofol in avian eggs     

A J Krynitsky  C J Stafford  S N Wiemeyer 《Journal of the Association of Official Analytical Chemists》1988,71(3):539-542

Dicofol in avian eggs was completely oxidized to dichlorobenzophenone (DCBP) when a hexane Soxhlet extraction procedure was used. This degradation did not occur with other avian tissues (muscle and liver). For this reason, a combined extraction-cleanup column chromatographic procedure, without added heat, was developed for the determination of dicofol in avian eggs. Homogenized subsamples of eggs were mixed with sodium sulfate, and the mixture was added as the top layer on a column prepacked with Florisil. The dicofol and other compounds of interest were then eluted with ethyl ether-hexane. The extracts, relatively free from lipids, were quantitated on a gas chromatograph equipped with a 63Ni electron-capture detector and a methyl silicone capillary column. Recoveries from chicken eggs, fortified with dicofol and other DDT-related compounds, averaged 96%. Analysis of eggs of eastern screech-owls, fed a meat diet containing 10 ppm technical Kelthane, showed that both dicofol and DCBP were present. Results were confirmed by gas chromatography/mass spectrometry. This method is rapid and reliable, involves a minimum of sample handling, and is well suited for high volume determination of dicofol in eggs and other avian tissues.  相似文献   

Global desertification: building a science for dryland development   总被引：6，自引：0，他引：6  

Reynolds JF  Smith DM  Lambin EF  Turner BL  Mortimore M  Batterbury SP  Downing TE  Dowlatabadi H  Fernández RJ  Herrick JE  Huber-Sannwald E  Jiang H  Leemans R  Lynam T  Maestre FT  Ayarza M  Walker B 《Science (New York, N.Y.)》2007,316(5826):847-851

In this millennium, global drylands face a myriad of problems that present tough research, management, and policy challenges. Recent advances in dryland development, however, together with the integrative approaches of global change and sustainability science, suggest that concerns about land degradation, poverty, safeguarding biodiversity, and protecting the culture of 2.5 billion people can be confronted with renewed optimism. We review recent lessons about the functioning of dryland ecosystems and the livelihood systems of their human residents and introduce a new synthetic framework, the Drylands Development Paradigm (DDP). The DDP, supported by a growing and well-documented set of tools for policy and management action, helps navigate the inherent complexity of desertification and dryland development, identifying and synthesizing those factors important to research, management, and policy communities.  相似文献   

Letter to the editor     

Stafford K  Williamson N 《Journal of veterinary medical education》2011,38(3):210

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If the draft is abolished: can the cost be estimated?     

Rodgers W  Sonquist J  Stafford F 《Science (New York, N.Y.)》1969,164(3885):1223-1224

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