Comparative immunological and microbiological aspects of paratuberculosis as a model mycobacterial infection     

Whittington RJ  Begg DJ  de Silva K  Plain KM  Purdie AC 《Veterinary immunology and immunopathology》2012,148(1-2):29-47

Paratuberculosis or Johne's disease of livestock, which is caused by Mycobacterium avium subsp. paratuberculosis (MAP), has increased in prevalence and expanded in geographic and host ranges over about 100 years. The slow and progressive spread of MAP reflects its substantial adaptation to its hosts, the technical limitations of diagnosis, the lack of practical therapeutic approaches, the lack of a vaccine that prevents transmission and the complexity and difficulty of the on-farm control strategies needed to prevent infection. More recently evidence has accumulated for an association of MAP with Crohn's disease in humans, adding to the pressure on animal health authorities to take precautions by controlling paratuberculosis. Mycobacterial infections invoke complex immune responses but the essential determinants of virulence and pathogenesis are far from clear. In this review we compare the features of major diseases in humans and animals that are caused by the pathogenic mycobacteria M. ulcerans, M. avium subsp. avium, M. leprae, M. tuberculosis and MAP. We seek to answer key questions: are the common mycobacterial infections of humans and animals useful "models" for each other, or are the differences between them too great to enable meaningful extrapolation? To simplify this, the immunopathogenesis of mycobacterial infections will be defined at cellular, tissue, animal and population levels and the key events at each level will be discussed. Many pathogenic processes are similar between divergent mycobacterial diseases, and at variance between virulent and avirulent isolates of mycobacteria, suggesting that the research on the pathogenesis of one mycobacterial disease will be informative for the others.  相似文献   

Serum and plasma cardiac troponin I concentrations in clinically normal Thoroughbreds in training in Australia     

Begg LM  Hoffmann KL  Begg AP 《Australian veterinary journal》2006,84(9):336-337

Cardiac troponin I is a potentially useful test to identify cardiac muscle damage in the horse. Measurements of cardiac troponin I from serum or heparinised plasma samples from 23 clinically normal Thoroughbred horses in race training were analysed through a standard Australian commercial laboratory using the ADVIA Centaur Assay. The cardiac troponin I concentrations were < 0.15 microg/L from all samples. The test was then validated using macerated equine myocardium. Cardiac troponin I concentration may be useful in determining whether poor performance in Thoroughbred horses is related to active myocardial disease.  相似文献   

Effect of changes in hook pattern and size on catch rate, hooking location, injury and bleeding for a number of tropical reef fish species     

Amos Mapleston  David Welch  Gavin A. Begg  Mark McLennan  David Mayer  Ian Brown 《Fisheries Research》2008,91(2-3):203-211

The Queensland Great Barrier Reef line fishery in Australia is regulated via a range of input and output controls including minimum size limits, daily catch limits and commercial catch quotas. As a result of these measures a substantial proportion of the catch is released or discarded. The fate of these released fish is uncertain, but hook-related mortality can potentially be decreased by using hooks that reduce the rates of injury, bleeding and deep hooking. There is also the potential to reduce the capture of non-target species though gear selectivity. A total of 1053 individual fish representing five target species and three non-target species were caught using six hook types including three hook patterns (non-offset circle, J and offset circle), each in two sizes (small 4/0 or 5/0 and large 8/0). Catch rates for each of the hook patterns and sizes varied between species with no consistent results for target or non-target species. When data for all of the fish species were aggregated there was a trend for larger hooks, J hooks and offset circle hooks to cause a greater number of injuries. Using larger hooks was more likely to result in bleeding, although this trend was not statistically significant. Larger hooks were also more likely to foul-hook fish or hook fish in the eye. There was a reduction in the rates of injuries and bleeding for both target and non-target species when using the smaller hook sizes. For a number of species included in our study the incidence of deep hooking decreased when using non-offset circle hooks, however, these results were not consistent for all species. Our results highlight the variability in hook performance across a range of tropical demersal finfish species. The most obvious conservation benefits for both target and non-target species arise from using smaller sized hooks and non-offset circle hooks. Fishers should be encouraged to use these hook configurations to reduce the potential for post-release mortality of released fish.  相似文献   

Stopped in its tracks: how λ‐cyhalothrin can break the aphid transmission of a potato potyvirus          下载免费PDF全文

Brian Fenton  William T Salter  Gaynor Malloch  Graham Begg  Eric Anderson 《Pest management science》2015,71(12):1611-1616

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Thoracolaryngeal reflex latencies in Thoroughbred horses with recurrent laryngeal neuropathy     

Curtis RA  Hahn CN  Evans DL  Williams T  Begg L 《Veterinary journal (London, England : 1997)》2005,170(1):67-76

Electrolaryngeography was used to study the latencies of the thoracolaryngeal adductor reflex in Thoroughbred horses with and without recurrent laryngeal neuropathy (RLN). Latencies were compared in horses with grades 1 and 2 RLN, diagnosed by endoscopy in resting horses. The reliability of the measurements, effect of sedation and correlations of latencies with age of the horse were also studied. There was no effect of sedation on reflex latency periods. The latency of the reflex period measured to a convolved peak of the electromyographic response was significantly different in horses with grades 1 and 2 disease; medians and quartile ranges were 0.067 (0.065-0.073) and 0.072 (0.068-0.074) s, respectively (P<0.05). Significant associations were found between reflex latencies and both horse age and the grade of RLN. Reflex latency measurements are reliable and sensitive, and may assist with the clinical appraisal of Thoroughbred horses with RLN.  相似文献   

加强协作与交流推动乳业全球化进程     

Jim Begg 《中国乳业》2006,(11):18-19

刚才各位乳业高层的演讲给我留下了非常深刻的印象，我们也是密切关注他们是不是能够安现他们的业务目标。为股东带来价值。是否有能力整合整个乳品产业的供应链。  相似文献   

Discrimination between Icelandic cod (Gadus morhua L.) populations from adjacent spawning areas based on otolith growth and shape     

Groa Petursdottir  Gavin A. Begg  Gudrun Marteinsdottir   《Fisheries Research》2006,80(2-3):182-189

Studies on Atlantic cod (Gadus morhua L.) have demonstrated extensive variation in life history characteristics among populations exposed to different environmental conditions. In Iceland, cod sampled from adjacent spawning areas, within the main spawning area at the southwest coast, exhibit variation in vital life history characteristics. In this study, we investigated the stock structure of Icelandic cod on the main spawning grounds to discriminate between these adjacent spawning groups by using otolith growth and shape. Otolith growth was based on annual increment width estimated for the major age groups (6–7 year olds) of the spawning stock. Otolith shape was determined using Fourier analysis and compared among cod sampled from the different spawning areas with stepwise canonical discriminant analysis (CDA). We found significant differences in growth and otolith shape between adjacent spawning groups of cod where those sampled close to the coast differed from those that were sampled further out on the bank and continental shelf. Our results suggest that these cod may belong to different populations and the large and fast growing cod spawning in the coastal area may need special protection given their significance to the overall productivity of the stock.  相似文献   

Percy Edwin Sykes     

L Begg 《Australian veterinary journal》2014,92(4):100-100

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