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151.
152.
Twenty-seven of 427 Angora goats of mixed age became blind within a week of consuming large amounts of Stypandra glauca ("nodding blue lily"). A further 200 goats were depressed for several weeks, but most subsequently recovered. Blindness was associated with optic nerve neuropathy which is postulated to have followed compression of the optic nerves within the bony optic canals as a result of severe myelin oedema. Histologically, the intracanalicular portion of the optic nerve was sclerotic, while the intracranial portion of the optic nerve and the optic tracts were degenerating. The retrobulbar portion of the optic nerve was relatively unaffected. In addition, multifocal retinal photoreceptor degeneration was found ophthalmoscopically and histologically. The syndrome was not reproduced during a trial in which 2 goats were fed 4 and 20 kg of S. glauca harvested after it had finished flowering, more than 3 weeks after the first natural cases of blindness. Based on epidemiological and pathological data we propose that S. glauca is toxic to stock, but only for a short period while flowering in spring.  相似文献   
153.
Objective To assess the validity of claims that heavy metal contamination from an open-cut mine caused the death of 226 cattle on a nearby farm over a period of 18 months, and to investigate other possible contributing factors.
Procedure A retrospective assessment of previous investigations combinded with additional chemical analyses.
Results Extensive chemical analyses produced no evidence of heavy metal contamination associated with the mine. Analysis of bones indicated exposure to fluoride in greater than normal amounts. The main source of fluoride seems to have been gypsum that was included in a feed supplement and also ingested from fertiliser dumps on paddocks. The gypsum itself may have contributed significantly to the ill health. Other factors probably affected some classes of animals, notably the young calves.
Conclusions What originally seemed to be a disease problem of single aetiology probably was an expression of interacting multifactorial causes. This investigation has highlighted the potential toxicity of gypsum to livestock and the need for further studies to establish its basis.  相似文献   
154.
Non-regulatory animal health issues, such as Johne's disease, infectious bovine rhinotracheitis (IBR) and mastitis will become increasing important, with ongoing globalisation of markets in animals and animal products. In response, Ireland may need to broaden the scope of its national animal health services. However, there have been concerns about the respective roles and responsibilities (both financial and otherwise) of government and industry in any such moves. This paper argues the case for increased private sector involvement in Ireland's national animal health services, based both on theoretical considerations and country case studies (the Netherlands and Australia). The Dutch and Australian case studies present examples of successful partnerships between government and industry, including systems and processes to address non-regulatory animal health issues. In each case, the roles and responsibilities of government are clear, as are the principles underpinning government involvement. Furthermore, the roles and responsibilities (financial and otherwise) of the Dutch and Australian industry are determined through enabling legislation, providing both legitimacy and accountability. There are constraints on the use of EU and national government funds to support non-regulatory animal health services in EU member states (such as Ireland and the Netherlands).  相似文献   
155.
Infectious bovine rhinotracheitis (IBR), caused by bovine herpes virus 1 (BoHV-1), may result in various clinical consequences, including severe respiratory disease and conjunctivitis, venereal disease and reduced reproductive performance and abortion. This paper presents the serosurveillance findings from an intake of bulls into a performance testing station in Ireland during November 2007. The herd and within-herd BoHV-1 prevalence in 53 Irish beef herds and the risk factors for infection in these herds were determined, among bulls entering a beef performance testing station in Ireland. BoHV-1 status was determined for 41 herds, of which 30 (73.2%) herds were infected and the mean within-herd BoHV-1 prevalence was 28 (± 20)%. Multivariate exact logistic modelling revealed increasing numbers of contiguous herds and decreasing percentage of males within the herd as significant risk factors associated with infected herds. These findings highlight the high prevalence of BoHV-1 infection in those Irish beef herds that submitted bulls to this performance testing station, and raise concerns regarding IBR control nationally.  相似文献   
156.
157.
The metabolism of 14C-labeled 3-phenoxybenzoic acid, PBA, has been studied in cotton, vine, broad bean, soya bean, pea, lettuce, and tomato, using abscised leaves. PBA was converted into a range of polar products by esterification with glucose (in cotton and other species) and with glucosylarabinose and glucosylxylose (especially in vine leaves). Uptake of the glucose ester itself by cotton leaves also led to conversion into a more polar conjugate, probably the glucosylarabinose ester, which was not detectable following uptake of PBA. When PBA was applied to the surface of intact cotton leaves, it was slowly converted into products similar to those above.  相似文献   
158.
Polymorphonuclear (PMN) cells of more than 90% viability and 92% purity were isolated from the peripheral blood of buffaloes. The cationic proteins were extracted with 0.2 mol/L sodium acetate, pH 4.0 from the granules in the PMN and subjected to both non-denaturing and denaturing acid urea polyacrylamide gel electrophoresis (AUPAGE) for identification of myeloperoxidase (MPO), lysozyme, protease activity and lactoferrin. Protease was identified using -naphthyl acetate as substrate, while lactoferrin was identified using a reference lactoferrin from bovine milk in AUPAGE, and by double immunodiffusion and Western blot techniques. Based on AUPAGE, lysozyme was found to be most cationic of all the proteins and peptides from the PMN granules as was evident from reference lysozyme run. The results indicated that the granules in buffalo PMN cells have lysozyme, protease, MPO and lactoferrin.  相似文献   
159.
Singh, V.K., More, T. and Singh, S., 1997. The effect of activation of granulocytes on enzyme release and hydrogen peroxide and superoxide production in buffaloes. Veterinary Research Communications, 21 (4), 241-247Polymorphonuclear cells kill microorganisms by the stock of antibiotic proteins and peptides stored in their lysosomal granules and have the ability to produce reactive oxygen intermediates (ROI) such as H2O2, O 2 , and HOCl. Since the components involved in the microbicidal functions of buffalo (Bos bubalis) polymorphonuclear cells (PMN) have not been characterized, an assessment was made of the levels of various enzymes, the extent of extracellular release of these enzymes, and also their ability to produce H2O2/O 2 upon activation with opsonized zymosan (OZ) or lipopolysaccharide (LPS). Using GPC-HPLC, OZ was shown to be a more potent secretagogue than LPS, causing a significantly greater release of low-molecular-weight components. Varying levels of the enzymes (myeloperoxidase, lactate dehydrogenase, acid and alkaline phosphatases, -galactosidase, -D-glucuronidase, elastase and lysozyme) were recorded in the buffalo PMN and both the activators (OZ and LPS) caused significant release of all the enzymes except alkaline phosphatase. Both the activators also caused a significant increase in H2O2/O 2 production by the PMN. However, OZ caused a more pronounced activation than LPS. The studies revealed the presence of oxygen-dependent and oxygen-independent microbicidal systems with buffalo PMN, which responded more effectively to zymosan activation.  相似文献   
160.
The conclusion from the randomised badger culling trial was that localised badger culling not only fails to control but can actually increase the incidence of bovine tuberculosis in cattle. Professor Simon More and colleagues from University College Dublin question that conclusion, arguing that the data do not provide sufficient evidence to rule out alternative hypotheses.  相似文献   
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