Characterization of ovine PrP gene promoter activity in N2a neuroblastoma and ovine foetal brain cell lines   总被引：1，自引：0，他引：1  

G. T. O'Neill  K. Donnelly  E. Marshall  D. Cairns  W. Goldmann  N. Hunter 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2003,120(2):114-123

  相似文献   

Responses of ponies to equid herpesvirus-1 Iscom vaccination and challenge with virus of the homologous strain     

D. Hannant  D.M. Jessett  T. O'Neill  C.A. Dolby  R.F. Cook  J.A. Mumford 《Research in veterinary science》1993,54(3):299

An experimental (Iscom) vaccine previously shown to protect hamsters from lethal challenge with equid herpesvirus-1 (Ehv-1), was tested in horses. Vaccination with Ehv-1 Iscoms induced serum antibodies to the major virus glycoproteins gp10, 13, 14, 17, 18 and 21/22a, whereas antibody responses to gp2 were weak or absent. High levels of virus neutralising antibody of long duration were induced, but did not prevent challenge infection with virus of the homologous strain. However, in the vaccinated ponies there was a significant reduction in clinical signs, nasal virus excretion and cell associated viraemia compared with age-matched unvaccinated controls. There was a strong correlation between pre-challenge levels of serum virus neutralising antibody and the duration and total amount of virus excreted from the nasopharynx.  相似文献   

Serological responses of specific pathogen-free foals to equine herpesvirus-1: primary and secondary infection, and reactivation.     

J S Gibson  T O'Neill  A Thackray  D Hannant  H J Field 《Veterinary microbiology》1992,32(3-4):199-214

Serum antibody (virus neutralisation, complement fixation, IgM and IgG) responses to equine herpesvirus-1 (EHV-1) infection were measured in six foals which were initially free from EHV-1 and EHV-4 infection and maternally-derived antibodies. Following primary infection, high titres of virus neutralisation and complement fixation antibodies were detectable against EHV-1, however, corresponding antibody levels against EHV-4 were low or inapparent, although the two viruses share a number of cross-reactive epitopes. In addition, following the primary infection with EHV-1, IgM levels increased before those of IgG, virus neutralisation and complement fixation antibodies, peaked sooner and thereafter declined. Stimulation of IgM levels was observed on secondary infection with EHV-1 given 61 days later. In contrast, IgG, virus neutralisation and complement fixation antibodies following primary infection were more sustained and no increase in their levels was observed on secondary infection. No consistent changes in IgM or IgG levels were seen after administration of dexamethasone to reactivate latent virus.  相似文献   

Transmutation and functional representation of heterogeneous landscapes   总被引：3，自引：0，他引：3  

Anthony W. King  Alan R. Johnson  Robert V. O'Neill 《Landscape Ecology》1991,5(4):239-253

Models of local small-scale ecological processes can be used to describe related processes at larger spatial scales if the influences of increased scale and heterogeneity are carefully considered. In this paper we consider the changes in the functional representation of an ecological process that can occur as one moves from a local small-scale model to a model of the aggregate expression of that process for a larger spatial extent. We call these changes spatial transmutation. We specifically examine landscape heterogeneity as a cause of transmutation. Spatial transmutation as a consequence of landscape heterogeneity is a source of error in the prediction of aggregate landscape behavior from smaller scale models. However, we also demonstrate a procedure for taking advantage of spatial transmutation to develop appropriately scaled landscape functions. First a mathematical function describing the process of interest as a local function of local variables is defined. The spatial heterogeneity of the local variables is described by their statistical distribution in the landscape. The aggregate landscape expression of the local process is then predicted by calculating the expected value of the local function, explicitly integrating landscape heterogeneity. Monte Carlo simulation is used to repeat the local-to-landscape extrapolation for a variety of landscape patterns. Finally, the extrapolated landscape results are regressed on landscape variables to define response functions that explain a useful fraction of the total variation in landscape behavior. The response functions are hypotheses about the functional representation of the local process at the larger spatial scale.  相似文献   

An enzyme immunoassay to measure canine circulating fibronectin     

O'Neill S  Boothby JT  Feldman BF 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1986,15(1):22-26

A competitive enzyme immunoassay has been used to detect and quantitate fibronectin in canine plasma. In this test, purified fibronectin, bound to microtiter plates, competes with plasma fibronectin for the conjugated antibody, rabbit-anticanine, fibronectin-horseradish peroxidase. The assay could detect fibronectin in purified standards from 58 ng/ml to 580 microgram/ml. The range of 1-100 microgram/ml was linear for plasma samples diluted 1:10, allowing samples with fibronectin concentrations from 10-1000 microgram/ml to be easily measured by this method. The mean normal fibronectin concentration of 132 dogs, by this method, was determined to be 320 +/- 74 microgram/ml.  相似文献   

Scale of heterogeneity of forage production and winter foraging by elk and bison     

L. L. Wallace  M. G. Turner  W. H. Romme  R. V. O'Neill  Yegang Wu 《Landscape Ecology》1995,10(2):75-83

The relationship between fine-scale spatial patterns of forage abundance and the feeding patterns of large ungulates is not well known. We compared these patterns for areas grazed in winter by elk and bison in a sagebrush-grassland landscape in northern Yellowstone National Park. At a fine scale, the spatial distribution of mapped feeding stations in 30 m × 30 m sites was found to be random where there were no large patches devoid of vegetation. In areas similar to the mapped sites, the underlying spatial distribution pattern of biomass was also determined to be random. At a broad scale, forage biomass differed among communities across the northern range but forage quality did not. These results suggest that ungulates are feeding randomly within forage patches (fine scale) but may select feeding sites based upon forage abundance at broader, landscape scales. Contrary to what has been suggested in other systems, ungulates were not overmatching at finer scales.  相似文献   

Prepenetration stages in infection of clematis by Phoma clematidina     

P. van de Graaf †  M. E. Joseph  J. M. Chartier-Hollis  T. M. O'Neill 《Plant pathology》2002,51(3):331-337

A detailed study of conidial germination, germ-tube growth and the formation of infection structures in Phoma clematidina , the causal agent of clematis wilt, is described for two clematis varieties differing in disease resistance. On both the resistant and susceptible varieties, the fungus entered leaves and stems by direct penetration of the cuticle, often, but not always, following the formation of infection structures. More germ tubes per conidium were formed on the susceptible host, but these germ tubes were on average shorter than on the resistant host. Although germ tubes regularly entered the plant via trichomes, stomata were not found to be sites of entry. Following penetration of the cuticle of resistant plants, germ-tube growth was sometimes restricted to the subcuticular region, and halo formation occurred at the sites where penetration was attempted. Subcuticular growth and halo formation were not observed on susceptible plants. These observations may partly explain the resistance of small-flowered clematis varieties to P. clematidina .  相似文献   

A survey of northern Victorian dairy farmers to investigate dairy calf management: colostrum feeding and management          下载免费PDF全文

AJ Phipps  DS Beggs  AJ Murray  PD Mansell  MF Pyman 《Australian veterinary journal》2018,96(4):101-106

Objectives

To describe colostrum management practices carried out in northern Victorian dairy herds and to identify weaknesses in these areas that may affect calf health and welfare by comparing the results with the current industry recommendations

Methods

A questionnaire to obtain information about colostrum management and calf‐rearing practices was sent to commercial dairy farming clients of Rochester Veterinary Practice between June and September 2013. The questionnaire consisted of a general herd overview and colostrum harvesting practices.

Results

The response rate was 39% (58/150). Many dairy producers were not meeting the current industry recommendations in the following areas: (1) time of removal calf from the dam, (2) relying on calf suckling colostrum from the dam to achieve adequate passive transfer, (3) failing to supplement calves with colostrum, (4) feeding inadequate volumes of colostrum, (5) delayed colostrum harvesting, (6) pooling of colostrum, (7) failing to objectively assess colostrum quality or relying on visual assessment and (8) storing colostrum for a prolonged periods of time at ambient temperatures.

Conclusion

The results from this survey highlight the need for greater awareness of industry standards for colostrum management and feeding hygiene.

  相似文献   

BVDV in Australian alpacas: natural infection and clinical profiles following co‐mingling with a persistently infected heifer          下载免费PDF全文

CA Evans  E Erregger  F Hemmatzadeh  PD Cockcroft 《Australian veterinary journal》2018,96(7):262-268

  相似文献   

Seroprevalence of antibodies to Pestivirus infections in South Australian sheep flocks          下载免费PDF全文

CA Evans  SR Lanyon  RM O’Handley  MP Reichel  PD Cockcroft 《Australian veterinary journal》2018,96(8):312-314

  相似文献