Investigations into the toxicity of Echium plantagineum in sheep: 2. Pen feeding experiments     

JT SEAMAN  RJ DIXON† 《Australian veterinary journal》1989,66(9):286-292

In a pen feeding trial fresh Echium plantagineum was fed as the sole diet to crossbred sheep with or without a history of previous access to the plant. Control groups received a diet of lucerne chaff and oats. During the trial, sheep on the Echium diet lost weight and deaths occurred with histological evidence of excessive copper accumulation, usually accompanied by pyrrolizidine alkaloid damage, in the liver and biochemical evidence of liver toxicity. It is concluded that E. plantagineum alone is not a suitable fodder for sheep and can be toxic due to its pyrrolizidine alkaloid content and high copper to molybdenum ratio.  相似文献   

Lithospheric Contributions to Arc Magmatism: Isotope Variations Along Strike in Volcanoes of Honshu, Japan     

AB Kersting  RJ Arculus  DA Gust 《Science (New York, N.Y.)》1996,272(5267):1464-1468

Major chemical exchange between the crust and mantle occurs in subduction zone environments, profoundly affecting the chemical evolution of Earth. The relative contributions of the subducting slab, mantle wedge, and arc lithosphere to the generation of island arc magmas, and ultimately new continental crust, are controversial. Isotopic data for lavas from a transect of volcanoes in a single arc segment of northern Honshu, Japan, have distinct variations coincident with changes in crustal lithology. These data imply that the relatively thin crustal lithosphere is an active geochemical filter for all traversing magmas and is responsible for significant modification of primary mantle melts.  相似文献   

Effect of a second treatment of prostaglandin F2α during the Ovsynch program on fixed-time artificial insemination conception rates and luteolysis in split-calving,pasture-fed dairy cows     

JM Rheinberger  DD Colson  DS Beggs  PD Mansell  MA Stevenson  RJ Rheinberger  MF Pyman 《Australian veterinary journal》2020,98(5):190-196

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The radio-frequency single-electron transistor (RF-SET): A fast and ultrasensitive electrometer     

RJ Schoelkopf  P Wahlgren  AA Kozhevnikov  P Delsing  DE Prober 《Science (New York, N.Y.)》1998,280(5367):1238-1242

A new type of electrometer is described that uses a single-electron transistor (SET) and that allows large operating speeds and extremely high charge sensitivity. The SET readout was accomplished by measuring the damping of a 1.7-gigahertz resonant circuit in which the device is embedded, and in some ways is the electrostatic "dual" of the well-known radio-frequency superconducting quantum interference device. The device is more than two orders of magnitude faster than previous single-electron devices, with a constant gain from dc to greater than 100 megahertz. For a still-unoptimized device, a charge sensitivity of 1.2 x 10(-5) e/hertz was obtained at a frequency of 1.1 megahertz, which is about an order of magnitude better than a typical, 1/f-noise-limited SET, and corresponds to an energy sensitivity (in joules per hertz) of about 41 Planck's over 2pi.  相似文献   

Oceanic Anoxia and the End Permian Mass Extinction   总被引：6，自引：0，他引：6  

PB Wignall  RJ Twitchett 《Science (New York, N.Y.)》1996,272(5265):1155-1158

Data on rocks from Spitsbergen and the equatorial sections of Italy and Slovenia indicate that the world's oceans became anoxic at both low and high paleolatitudes in the Late Permian. Such conditions may have been responsible for the mass extinction at this time. This event affected a wide range of shelf depths and extended into shallow water well above the storm wave base.  相似文献   

16S rDNA comparison demonstrates near identity between an United Kingdom Haemobartonella felis strain and the American California strain     

Tasker S  Helps CR  Belford CJ  Birtles RJ  Day MJ  Sparkes AH  Gruffydd-Jones TJ  Harbour DA 《Veterinary microbiology》2001,81(1):73-78

A handful of North American (USA) strains of the uncultured erythrocytotrophic pathogen of cats, Haemobartonella felis, have been differentiated by comparison of the 16S rRNA gene sequences. Using this approach, an UK strain was characterised, providing an identity for a non-USA H. felis for the first time. This strain shared close phylogenetic homology with the USA Californian strain.  相似文献   

Arthropod-transmitted infectious diseases of cats     

SE Shaw  RJ Birtles  MJ Day 《Journal of Feline Medicine and Surgery》2001,3(4):193-209

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Development and use of real-time PCR to detect and quantify Mycoplasma haemocanis and “Candidatus Mycoplasma haematoparvum” in dogs     

E.N. Barker  S. Tasker  M.J. Day  S.M. Warman  K. Woolley  R. Birtles  K.C. Georges  C.D. Ezeokoli  A. Newaj-Fyzul  M.D. Campbell  O.A.E. Sparagano  S. Cleaveland  C.R. Helps 《Veterinary microbiology》2010,140(1-2):167-170

Two canine haemoplasma species have been recognised to date; Mycoplasma haemocanis (Mhc), which has been associated with anaemia in splenectomised or immunocompromised dogs, and “Candidatus Mycoplasma haematoparvum” (CMhp), recently described in an anaemic splenectomised dog undergoing chemotherapy. The study aim was to develop quantitative real-time PCR assays (qPCRs) incorporating an endogenous internal control to detect Mhc and CMhp and to apply these assays to DNA samples extracted from canine blood collected in Northern Tanzania (n = 100) and from dogs presented to a Trinidadian veterinary hospital (n = 185).QPCRs specific for Mhc and CMhp were designed using 16S rRNA gene sequence data, and each was duplexed with an assay specific for canine glyceraldehyde-3-phosphate dehydrogenase (GAPDH). The assays detected ≤10 copies of a sequence-specific haemoplasma plasmid per reaction and neither assay showed cross-reactivity with 10⁶ copies of the sequence-specific plasmid from the non-target canine haemoplasma species.Nineteen of the 100 Tanzanian samples (19%) were positive for Mhc alone and one (1%) was dually infected. One Trinidadian sample was negative for canine GAPDH DNA and was excluded from the study. Of the 184 remaining Trinidadian samples, nine (4.9%) were positive for Mhc alone, five (2.7%) for CMhp alone, and two (1.1%) dually infected.This is the first report of canine haemoplasma qPCR assays that use an internal control to confirm the presence of amplifiable sample DNA, and their application to prevalence studies. Mhc was the most commonly detected canine haemoplasma species.  相似文献   

Cross‐sectional survey of health management and prevalence of vector‐borne diseases,endoparasites and ectoparasites in Samoan dogs          下载免费PDF全文

RJ Carslake  KE Hill  K Sjölander  SF Hii  D Prattley  E Acke 《Australian veterinary journal》2017,95(12):462-468

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Epizootics of sudden death in tammar wallabies (Macropus eugenii) associated with an orbivirus infection     

KA Rose  PD Kirkland  RJ Davis  D Blumstein  LI Pritchard  KM Newberry  RA Lunt 《Australian veterinary journal》2012,90(12)

Epizootics of sudden death in tammar wallabies (Macropus eugenii) occurred at six research facilities and zoological gardens in New South Wales, Australia, in late 1998 and at one Queensland research facility in March 1999. There were 120 confirmed tammar wallaby deaths during this period; however, population censuses indicated that up to 230 tammar wallabies may have died. The majority of animals died without premonitory signs. A small proportion of wallabies exhibited increased respiratory rate, sat with a lowered head shortly before death or were discovered in lateral recumbency, moribund and with muscle fasciculations. Gross postmortem findings consistently included massive pulmonary congestion, mottled hepatic parenchyma and subcutaneous oedema throughout the hindlimbs and inguinal region. Approximately 30% of the animals examined also had extensive haemorrhage within the fascial planes and skeletal muscle of the hindlimb adductors, inguinal region, ventral thorax, dorsal cervical region and perirenal retroperitoneal area. The tissues of affected animals became autolytic within a short period after death. Bacteriological examination of tissues from 14 animals did not provide any significant findings. Toxicological examination of the gastric and colonic contents of four animals did not reveal evidence of brodifacoume or other rodenticides. Viruses from the Eubenangee serogroup of the Orbivirus genus were isolated from the cerebral cortex of nine, and the myocardium of two, tammar wallabies and the liver and intestine of another tammar wallaby. A similar orbivirus was also isolated from the cerebrospinal fluid of another tammar wallaby that died suddenly. The disease agent appears to be a previously unrecognised orbivirus in the Eubenangee serogroup. This is the first report of epizootics of sudden deaths in tammar wallabies apparently associated with an orbivirus infection.  相似文献