Timing of large movement events of pond-breeding amphibians in Western Massachusetts, USA     

Brad C. Timm  Kevin McGarigal 《Biological conservation》2007,136(3):442-454

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Severe psoroptic mange and endoparasitism in a Nubian doe.          下载免费PDF全文

J Lofstedt  S D White  D S Garlick    P Hanna 《The Canadian veterinary journal. La revue veterinaire canadienne》1994,35(11):716-718

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Immunisation of pregnant sows with a live Salmonella cholerae suis vaccine     

J. Hanna  W.A. Ellis  J.J. O&#x;Brien 《Veterinary microbiology》1979,3(4):303-309

Sows were immunised subcutaneously with a live Salmonella cholerae suis (SCS) vaccine prior to farrowing. Serological tests demonstrated a high level of SCS colostral antibodies at parturition. Piglet sera negative for antibodies at birth contained a high level of SCS antibodies 24 h after the ingestion of vaccinated sow colostrum. Experiments were carried out to establish if these maternally derived antibodies could protect the piglets against an intranasal (IN) challenge with a field isolate of SCS. It was concluded that pregnant sows could be safely immunised with a live SCS vaccine thus providing their piglets with a passive immunity which protected them against an intranasal challenge.  相似文献   

Prince Edward Island. Papillomatous digital dermatitis in a Canadian dairy herd.   总被引：1，自引：1，他引：0       下载免费PDF全文

P Hanna  J Lofstedt    P Duivenvoorden 《The Canadian veterinary journal. La revue veterinaire canadienne》1994,35(10):657

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Use of PPD and phosphatide antigens in an ELISA to detect the serological response in experimental bovine tuberculosis   总被引：3，自引：0，他引：3  

J Hanna  S D Neill  J J O'Brien 《Research in veterinary science》1989,47(1):43-47

Five calves from tuberculosis free herds were each inoculated intranasally with 10(6) viable organisms of a field isolate of Mycobacterium bovis. Four of the calves developed acute tuberculosis. ELISAs employing protein and phosphatide extracts of M bovis as antigens were used to monitor the humoral response of the infected calves. Fourteen days after infection there was a dramatic increase in the level of antibodies demonstrated by the phosphatide antigen. This increase coincided with the first appearance of signs of the disease. The results suggest that the phosphatide antigen may be of potential value in detecting a humoral response, if present, in cattle infected with M bovis. The tests employing the protein antigen demonstrated a humoral response in only one of the infected calves and emphasises the importance of antigen selection to detect antibodies in tuberculous animals.  相似文献   

Use of immunosorbent-purified antigens of Fasciola hepatica in enzyme immunoassays   总被引：1，自引：0，他引：1  

A Trudgett  A Anderson  R E Hanna 《Research in veterinary science》1988,44(2):262-263

A monoclonal antibody specific for the T1 tegumental antigen of Fasciola hepatica was used as a solid-phase immunosorbent for the purification of T1 antigen from homogenised mature F hepatica. Material fractionated by this technique was successfully used in enzyme-linked immunoassays to detect antibodies to F hepatica in sera from sheep and cattle. Species differences in response to infection by F hepatica were demonstrated.  相似文献   

Germination of <Emphasis Type="Italic">Plasmodiophora brassicae</Emphasis> resting spores stimulated by a non-host plant     

Hanna?FribergEmail author  Jan?Lagerl?f  Birgitta?R?mert 《European journal of plant pathology / European Foundation for Plant Pathology》2005,113(3):275-281

Plant-induced germination of Plasmodiophora brassicae resting spores was studied in a laboratory experiment. Spore reaction was analysed in nutrient solution with exudates from growing roots of different plant species – one host plant (Brassica rapa var. pekinensis) and four non-host plants (Lolium perenne, Allium porrum, Secale cereale and Trifolium pratense) – and in controls with distilled water and nutrient solution. It was found that root exudates from L. perenne stimulated spore germination more than exudates from the other plants, including those from the host plant. The effect could not be explained by differences in the nutritional composition of the solutions due to differential uptake of the plant species, or by differences in root activity, measured as exudation of soluble sugars. This is the first time such a separation of factors has been done in analysing the influence of plants on P. brassicae germination. Although stimulation of P. brassicae resting spore germination is not restricted to the presence of host plants, it seems to vary depending on the plant species.  相似文献   

Development of a computerized systems model for health management decision support in growing hogs     

James W. Lloyd  Stephen B. Harsh  John B. Kaneene  Gerald D. Schwab  Brad J. Thacker  Andrew J. Thulin 《Preventive veterinary medicine》1994,19(3-4):249-265

A study was designed to provide decision support for health management in growing hogs. A dynamic, stochastic systems model for a confinement, continuous production hog growing enterprise (including nursery, grower and finisher phases) was developed to simulate the economic effects of disease, available floor space and feed additives using farm- specific data. Modeling techniques included: discrete and distributed (continuous) delays; triangular probability density functions; autocorrelation; table look-up functions; an alpha-beta tracker; non-linear, constrained optimization. The model was designed to be initialized with the system's current status, using an accompanying production/financial database to achieve individual-farm specificity. Initialization of rate variables required ‘reverse optimization’ of historical system performance. Model predictions are based on an adjustment approach, where changes in current performance are dictated by changes in disease rates, available floor space and feed additive use. These effects vary randomly, but are autocorrelated between production phases, between similar diseases and over time.  相似文献   

Transmission of tuberculosis from experimentally infected cattle to in-contact calves   总被引：5，自引：0，他引：5  

S D Neill  J Hanna  J J O'Brien  R M McCracken 《The Veterinary record》1989,124(11):269-271

Five of a group of six calves were inoculated with Mycobacterium bovis. Two more uninoculated calves were introduced to the group 84 days later. All the inoculated calves were subsequently shown to be excreting M bovis in nasal mucus. The uninoculated calf in the initial group of six became infected and subsequently excreted M bovis. The two uninoculated calves which were introduced later did not become infected. It was concluded that contact with nasal mucus from the infected cattle resulted in infection of the uninoculated calf and that the density of accommodation of animals excreting M bovis was an important factor in transmission of the disease.  相似文献   

Loss of a harvested fish species disrupts carbon flow in a diverse tropical river   总被引：1，自引：0，他引：1  

Taylor BW  Flecker AS  Hall RO 《Science (New York, N.Y.)》2006,313(5788):833-836

Harvesting threatens many vertebrate species, yet few whole-system manipulations have been conducted to predict the consequences of vertebrate losses on ecosystem function. Here, we show that a harvested migratory detrital-feeding fish (Prochilodontidae: Prochilodus mariae) modulates carbon flow and ecosystem metabolism. Natural declines in and experimental removal of Prochilodus decreased downstream transport of organic carbon and increased primary production and respiration. Thus, besides its economic value, Prochilodus is a critical ecological component of South American rivers. Lack of functional redundancy for this species highlights the importance of individual species and, contrary to theory, suggests that losing one species from lower trophic levels can affect ecosystem functioning even in species-rich ecosystems.  相似文献