Cohort survival patterns of walleye pollock, Theragra chalcogramma, in Shelikof Strait, Alaska: a critical factor analysis     

KEVIN M. BAILEY  RICHARD D. BRODEUR  ANNE B. HOLLOWED 《Fisheries Oceanography》1996,5(S1):179-188

A series of age-specific life tables for walleye pollock ( Theragra chalcogramma ) in the western Gulf of Alaska was compiled for the 1980-91 year classes. The life tables were utilized to perform an exploratory key factor analysis to examine the timing of critical periods in the recruitment process, evidence of density-dependence at different stages and trends in mortality rates. Early larval mortality was significantly correlated with generational mortality (In recruits/spawning bio-mass), but patterns in juvenile mortality also were similar to generational mortality and in some years were clearly dominant in determining the fate of a cohort. Density-dependent mortality, based on the correlation between mortality and initial abundance, was indicated only for the late larval to early juvenile stage. Time trends were marginally significant for juvenile mortality. It is speculated that the observed increase in juvenile mortality is associated with increasing abundance of arrowtooth flounder. Weaknesses in the data base are discussed; these along with the short time series involved make our conclusions tentative and subject to further study. We hypothesize that pollock recruitment levels can be established at any life stage depending on sufficient supply from prior stages, a type of dynamics which can be termed supply dependent multiple life stage control.  相似文献   

A comparison of the pathogenicity of two strains of hog cholera virus: 2. Virological studies     

S. KAMOLSIRIPRICHAIPORN  CJ MORRISSY  HA WESTBURY 《Australian veterinary journal》1992,69(10):245-248

Quantitative and qualitative differences were demonstrated in the amount of virus in a range of tissues from pigs infected with either the Weybridge or New South Wales (NSW) strains of hog cholera (HC) virus. The titre of the Weybridge strain in samples, as assessed by either virus titration in cell culture or by the density of specific fluorescing cells in tissue sections, was higher than that for the NSW strain. This correlated with the greater severity of the clinico-pathological syndrome induced by the Weybridge strain. The implications of the differences in the virus content of tissues in the diagnosis of HC is discussed as is the use of monoclonal antibodies to differentiate HC and bovine virus diarrhoea viruses.  相似文献   

Efficacy of erythromycin compared with penicillin/streptomycin for the treatment of virulent footrot in sheep   总被引：2，自引：0，他引：2  

JK WEBB WARE  CJ SCRIVENER  AL VIZARD 《Australian veterinary journal》1994,71(3):88-89

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Effect of storage of smears on the staining of ram spermatozoa by eosin or trypan blue     

P. SUTTIYOTIN  CJ THWAITES 《Australian veterinary journal》1994,71(3):87-87

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Effect of a single bout of high intensity exercise on lower respiratory tract contamination in the horse   总被引：1，自引：0，他引：1  

SL RAIDAL  DN LOVE  GD BAILEY 《Australian veterinary journal》1997,75(4):293-295

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Single-dose pharmacokinetics of cefazolin in bovine synovial fluid after intravenous regional injection     

H. GAGNON  I G. FERGUSON  M. G. PAPICH  I. V. BAILEY 《Journal of veterinary pharmacology and therapeutics》1994,17(1):31-37

Gagnon, H., Ferguson, J.G., Papich, M.G., Bailey, J.V. Single-dose pharmacokinetics of cefazolin in bovine synovial fluid after intravenous regional injection. J. vet. Pharmacol. Therap. 17, 31–37.
The pharmacokinetic properties of cefazolin in the synovial fluid of the tibiotarsal joint were determined in 10 healthy mature cattle after intravenous regional injection of 2 50 mg cefazolin. A pneumatic tourniquet was positioned proximal to the tibiotarsal joint and the intravenous injection was performed distal to the tourniquet. Synovial fluid concentrations of cefazolin increased in the first 30 mm and fluctuated between 54.7 ± 11.0 g/ml (mean ± SEM) and 73.2 ± 13.2 g/ml in the following 90 min while the tourniquet remained inflated. After tourniquet removal, synovial fluid concentration-time curves followed first-order one-compartment model decay in most of the animals with an elimination half-life of 0.82 h (harmonic mean). Therapeutic concentrations of cefazolin in the synovial fluid of normal joints were reached and this injection technique could be used as an alternative to systemic administration of antibiotics to provide adequate concentrations in a localized area.  相似文献   

Tracing the origins of White Tip disease of Cirsium arvense and its causal agent,Phoma macrostoma     

H C EVANS  M K SEIER  J‐A DERBY  S FALK  K L BAILEY 《Weed Research》2013,53(1):42-52

Cirsium arvense (Asteraceae) is known as creeping thistle in its native range in the UK and Canada thistle in its invasive North American range. Recently, the fungus Phoma macrostoma was registered in Canada as a bioherbicide in turfgrass, where it causes severe chlorosis (White Tip disease) and death of C. arvense and other broadleaved weeds. It was hypothesised that the disease originated in the UK on its thistle host and, therefore, that fungal isolates from both countries should be biologically and genetically similar. Twenty‐six strains in the genus Phoma– isolated during surveys in the UK – were compared morphologically with the type culture of P. macrostoma, tested for bioherbicidal activity using the inoculum mat bioassay and genetically screened with bioherbicide‐specific primers. White tip disease was found to be restricted to the eastern and southern counties of England. Phoma macrostoma was isolated consistently from diseased bleached tissues. Bioherbicidal isolates of P. macrostoma occupy a unique clade, which is phylogenetically distinct but morphologically indistinguishable from the type culture. Most isolates from the UK had the same bioherbicidal activity and similar genetic make‐up as strain SRC 94‐44B, the active ingredient in the registered Canadian product. The origin of all bioherbicidal strains found to date has a clear presence in both Canada and the UK, with strong genetic similarities, supporting the view of a common ancestry. Thus, on the evidence presented, the ‘white tip’ clade of P. macrostoma evolved in southern England. Therefore, the bioherbicide based on strain SRC 94‐44B should also be eligible for registration in the UK, based on the pest risk assessment data already available.  相似文献   

Model performance of tree height-diameter relationships in the central Congo Basin     

Elizabeth Kearsley  Pieter CJ Moonen  Koen Hufkens  Sebastian Doetterl  Janvier Lisingo  Faustin Boyemba Bosela  Pascal Boeckx  Hans Beeckman  Hans Verbeeck 《Annals of Forest Science》2017,74(1):7

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Ancient mantle in a modern arc: osmium isotopes in izu-bonin-mariana forearc peridotites   总被引：2，自引：0，他引：2  

IJ Parkinson  CJ Hawkesworth  AS Cohen 《Science (New York, N.Y.)》1998,281(5385):2011-2013

Mantle peridotites drilled from the Izu-Bonin-Mariana forearc have unradiogenic 187Os/188Os ratios (0.1193 to 0.1273), which give Proterozoic model ages of 820 to 1230 million years ago. If these peridotites are residues from magmatism during the initiation of subduction 40 to 48 million years ago, then the mantle that melted was much more depleted in incompatible elements than the source of mid-ocean ridge basalts (MORB). This result indicates that osmium isotopes record information about ancient melting events in the convecting upper mantle not recorded by incompatible lithophile isotope tracers. Subduction zones may be a graveyard for ancient depleted mantle material, and portions of the convecting upper mantle may be less radiogenic in osmium isotopes than previously recognized.  相似文献   

Shear-wave splitting and implications for mantle flow beneath the MELT region of the east pacific rise   总被引：1，自引：0，他引：1  

CJ Wolfe  SC Solomon 《Science (New York, N.Y.)》1998,280(5367):1230-1232

Shear-wave splitting across the fast-spreading East Pacific Rise has been measured from records of SKS and SKKS phases on the ocean-bottom seismometers of the Mantle Electromagnetic and Tomography (MELT) Experiment. The direction of fast shear-wave polarization is aligned parallel to the spreading direction. Delay times between fast and slow shear waves are asymmetric across the rise, and off-axis values on the Pacific Plate are twice those on the Nazca Plate. Splitting on the Pacific Plate may reflect anisotropy associated with spreading-induced flow above a depth of about 100 km, as well as a deeper contribution from warm asthenospheric return flow from the Pacific Superswell region.  相似文献