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31.
In recent years the vector-borne diseases (VBD) are (re)-emerging and spreading across the world having a profound impact on human and veterinary health, ecology, socio-economics and disease management. Arguably the best-documented example of veterinary importance is the recent twofold invasion of bluetongue (BT) in Europe. Much attention has been devoted to derive presence-absence habitat distribution models and to model transmission through direct contact. Limited research has focused on the dynamic modelling of wind mediated BT spread. This paper shows the results of a stochastic predictive model used to assess the spread of bluetongue by vectors considering both wind-independent and wind-mediated movement of the vectors. The model was parameterised using epidemiological knowledge from the BTV8 epidemic in 2006/2007 and the BTV1 epidemic in 2008 in South-France. The model correctly reflects the total surface of the infected zone (overall accuracy=0.77; sensitivity=0.94; specificity=0.65) whilst slightly overestimating spatial case density. The model was used operationally in spring 2009 to predict further spread of BTV1. This allowed veterinary officers in Belgium to decide whether there was a risk of introduction of BTV1 from France into Belgium and thus, whether there was a need for vaccination. Given the far distance from the predicted infected zone to the Belgian border, it was decided not to vaccinate against BTV1 in 2009 in Belgium.  相似文献   
32.
Over a year swabs were taken from 87 untreated bite wounds in dogs seen by veterinary practitioners in Harare, Zimbabwe. Swabs were also taken from normal skin adjacent to the wound site, and gingival swabs were collected from normal dogs coming to the same clinics. The swabs were cultured aerobically for pathogens, particularly Staphylococcus intermedius, and the antibiotic sensitivities of the pathogens were determined by disc diffusion assay. The most common pathogens isolated from the wounds were S intermedius (23 per cent), Escherichia coli (18 per cent) and non-lactose-fermenting coliforms (14 per cent). S intermedius was common on the normal skin of the dogs with infected wounds, and was associated with wounds on the abdomen, hindlimbs and tail and wounds that were more than three days old. This organism was, however, isolated only infrequently from the gums and there was little correlation in general between the prevalence of pathogens in the mouth and their prevalence in wounds. Of the S intermedius isolates from wounds, 30 per cent were resistant to penicillin and multiple antibiotic resistance was common among the enterobacterial isolates. The majority of the pathogens were sensitive to cotrimoxazole.  相似文献   
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: A nine-year-old male entire Labrador was diagnosed with pituitary dependent hyperadrenocorticism. Following seven months of successful mitotane therapy, the dog presented with marked weight gain, seborrhoea and alopecia. Routine clinicopathological analyses revealed marked hypercholesterolaemia. Serum total and free thyroxine (T4) concentrations were below their respective reference ranges. Serum thyroid stimulating hormone (cTSH) concentration was within reference range. TSH and thyrotropin releasing hormone (TRH) response tests revealed adequate stimulation of total T4 in both, and cTSH in the latter test. Magnetic resonance imaging revealed a mass arising from the pituitary fossa, with suprasellar extension. A diagnosis of tertiary hypothyroidism was made. Following four weeks of levothyroxine therapy, circulating cholesterol concentration had declined, weight loss had ensued and dermatological abnormalities had improved. Euthanasia was performed four months later due to the development of neurological signs. A highly infiltrative pituitary adenoma, with effacement of the overlying hypothalamus was identified on post mortem examination. Tertiary hypothyroidism has not been previously reported in dogs.  相似文献   
35.
Helminth infections of cattle affect productivity in all classes of stock, and are amongst the most important production-limiting diseases of grazing ruminants. Over the last decade, there has been a shift in focus in the diagnosis of these infections from merely detecting presence/absence of infection towards detecting its impact on production. This has been facilitated by studies observing consistent negative correlations between helminth diagnostic test results and measures of productivity. Veterinarians are increasingly challenged to consider the economic aspects of their work, and the use of these tests should now be integrated in economic evaluation frameworks for improved decision making. In this paper, we review recent insights in the farm-specific economic impact of helminth infections on dairy cattle farms as well as in farmer attitudes and behaviour regarding helminth control. Combining better economic impact assessments of helminth infections together with a deeper understanding of the non-economic factors that drive a farmer’s animal health decisions should result in more effective control strategies and increased farmer satisfaction.  相似文献   
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Traditional knowledge in northern Ethiopia points towards the root-stimulating properties of the latex found in Euphorbia abyssinica (EAG). Stem cuttings of EAG as well as cuttings of other species treated with EAG latex reportedly root easily in dry soil. This could be attributable to endogenous auxins contained in the latex. We screened EAG latex for auxins and precursor molecules using analytical LC-MS/MS, and tested the effect of EAG latex on the rooting of woody cuttings of Boswellia papyrifera, a threatened multipurpose tree. The EAG latex contained indole acetic acid (IAA) (0.06 μg/g latex), an auxin controlling apical dominance and lateral rooting, as well as IAA metabolites and conjugates. Boswellia cuttings treated with EAG latex rooted significantly sooner and showed higher survival ratios than untreated controls. EAG is widely available and its latex easy to obtain. Therefore it is a promising source of a natural plant growth regulator which may be used for improving low technology vegetative propagation of woody species in East and Northeast Africa, including the threatened Boswellia tree.  相似文献   
38.
Sheep were sensitized by repeated infection with Haemonchus contortus L3, followed by a 12 week rest period, and an abomasal cannula was surgically implanted in all sheep. Seven of the sensitized sheep were subsequently challenged with 50 000 H. contortus L3 while 4 control sheep were challenged with saline. Biopsy samples were taken using a fibreoptic endoscope on days 0, 1, 2, 3, 5, 7 and 28 after challenge and leukocyte subpopulations quantified by (immuno)histology. Differential blood cell counts were performed on the same days. At the end of the trial, sheep showed significantly reduced worm burdens compared to unsensitized control sheep, confirming their resistance status. Both blood and tissue eosinophils, as well as tissue γδ TCR+ cells were rapidly elevated by day 1 post L3 challenge (pc), peaking at day 3 pc. There was a slight increase in tissue CD4 T cells at day 2 pc, peaking at day 3 pc while no significant changes in CD8 T cells were observed. B cells (CD45R+) increased later into challenged tissues with a peak at 5 days pc. All tissue lymphocyte subpopulations as well as tissue and blood eosinophils were reduced by day 7 pc before increasing again at day 28 pc, suggesting separate responses to larval and adult antigens. In contrast, globule leukocytes and mucosal mast cells only showed one peak at day 5 pc and 28 pc, respectively. Unexpectedly, globule leukocytes correlated significantly with tissue eosinophils but not mucosal mast cells. The results are consistent with an early eosinophil-mediated killing of L3, possibly recruited by IL-5 produced by γδ T cells. In contrast to post-mortem studies, abomasal cannulation allowed sequential analysis of both early and late time points in the same animal, providing a more complete picture of cellular interactions at both peripheral and local sites, and their correlation with the different stages of parasite development.  相似文献   
39.
The Welfare Quality® project has developed an operational definition of farm animal welfare, which consists of 12 criteria grouped into four principles (‘good feeding’, ‘good housing’, ‘good health’ and ‘appropriate behaviour’). As part of a larger survey, 204 farmers, 72 vegetarians, and a representative sample of 459 adult citizens in Flanders (Belgium) scored the importance of each of the 12 criteria on a 1–10 scale, and divided 100 points across the four principles according to the perceived relative weights for farm animal welfare. These data were analysed to verify quantitatively whether (1) the grouping of 12 criteria into the four principles, and (2) the relative weights used by Welfare Quality® for aggregating the 12 criteria into an overall welfare judgement correspond with the perception of these three stakeholder groups from a region and setting not previously covered by Welfare Quality® studies. Moreover, the effects of various socio-demographic variables on the importance allocated to the welfare criteria and principles were investigated. Vegetarians and females gave consistently higher importance scores to all 12 criteria as compared with farmers, citizens and males, respectively, particularly for the (criteria belonging to the) principle ‘appropriate behaviour’. Farmers allocated more weight to ‘good feeding’ than did vegetarians or citizens. These differences confirm that farmers view animal welfare more in terms of biological functioning (instead of affective states or natural living) as compared to other citizens, and vegetarians in particular. As the concept has a different meaning to different people, any operational definition of animal welfare is unlikely to match equally well with the perception of every single stakeholder group or person. The structure of the Welfare Quality® operational definition with the 12 criteria aggregated into four principles, corresponds well with the opinion of the stakeholders as they judged all 12 criteria as rather important to extremely important for farm animal welfare. Factor analysis restricted to contain four factors confirmed the grouping of the criteria into the correct principles. Exploratory factor analysis using Eigenvalues > 1 as extraction criterion indicated, however, that from the citizen perspective two principles (‘good feeding & health’ and ‘appropriate behaviour & housing’) rather than four would suffice. The main discrepancy with the Welfare Quality® approach concerns the aggregation procedure: the stakeholders did not consider all four principles as equally important, and the relative importance allocated to criteria corresponded poorly across principles. Some of these discrepancies were consistent across the three different stakeholder groups.  相似文献   
40.
Members of the genus Habronema (Nematoda: Habronematidae) were preserved in 4 fixatives for examination with scanning electron microscopy (SEM). Tegumental features of the anterior and posterior extremities of these specimens were compared to evaluate the effect of the fixatives: modified Flemming's solution, glutaraldehyde (GA), Karnovsky's fixative and 70% ethanol. Fixatives were assessed on the appearance of the tegument, evidence of any wrinkling, shrinkage or swelling and the degree of extension in the male tail. Seventy per cent ethanol gave the most satisfactory results.  相似文献   
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