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31.
Objective To assess biosecurity practices in the fancy poultry show sector that would influence the establishment and spread of exotic diseases in poultry in New South Wales. Design A cross-sectional survey of 105 fancy poultry exhibitors at seven agricultural shows. Procedure Exhibitors were interviewed about biosecurity practices on their farms and their knowledge of exotic diseases. Poultry stewards at 18 shows were interviewed about biosecurity practices at their shows. Results Although many exhibitors travelled only short distances to attend shows, some exhibitors attended up to 30 shows per year and travelled interstate to exhibit poultry. A network diagram revealed extensive connections and interactions of poultry throughout the eastern half of NSW. Five of 18 shows included cash sales without any record of purchasers; 46% of exhibitors reintroduced exhibited birds back into their flocks without a quarantine period; and 16% failed to wash cages used to transport the birds. There was a general awareness that exhibition of birds posed a risk to flock health, but knowledge of avian influenza and practices that could be adopted to minimise the risk of disease introduction was limited. Conclusions The factors that could assist the establishment and spread of exotic diseases in poultry in NSW include the mixing of birds at shows, inadequate recording of exhibitor details at shows, inadequate biosecurity practices when reintroducing exhibited poultry back into flocks, cash sales associated with shows that did not include the collection of purchaser details, and inadequate identification of birds.  相似文献   
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Calcium has important physiological functions, and disorders of calcium homeostasis are frequent in horses. We have made important progress understanding equine calcium homeostasis; however, limited information on equine calcitonin (CT) is available, in part because of the lack of validated CT assays. To determine the CT response to high ionized calcium (Ca2+) concentrations in healthy horses, we induced hypercalcemia in 10 healthy horses using a calcium gluconate 23% solution (5 mg/kg; 120 mL/500 kg horse) infused over 4 min. Four horses were infused with 120 mL of 0.9% NaCl and used as controls. We validated a human-specific CT radioimmunoassay for use in horses. Serum Ca2+ concentrations increased from 6.2 ± 0.3 mg/dL to 9.9 ± 0.5 mg/dL (4 min; P < 0.01). Serum CT increased from 16.7 ± 8.0 pg/mL to 87.1 ± 55.8 pg/mL at 2 min, and 102.5 ± 51.1 pg/mL at 4 min (P < 0.01). Serum CT returned to baseline by 20 min, whereas serum Ca2+ returned to baseline by 40 min. Of interest, CT concentrations returned to baseline despite hypercalcemia, suggesting thyroid gland C-cell CT depletion. Resting CT values higher than 40 pg/mL were considered abnormally elevated. No significant changes in serum Ca2+ or CT concentrations were found in control horses. The coefficients of variation for the CT radioimmunoassay were lower than 11.9%. We conclude that the equine thyroid gland C-cell responds quickly to changes in extracellular Ca2+ concentrations by secreting large quantities of CT into the systemic circulation, indicating that CT is important in equine calcium homeostasis. The human CT radioimmunoassay can be used to measure changes in equine CT.  相似文献   
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Background: Disorders of calcium regulation are frequently found in humans with critical illness, yet limited information exists in foals with similar conditions including septicemia. The purpose of this study was to determine whether disorders of calcium exist in septic foals, and to determine any association with survival.
Hypothesis: Blood concentrations of ionized calcium (Ca2+) and magnesium (Mg2+) will be lower in septic foals with concomitant increases in parathyroid hormone (PTH), calcitonin (CT), and parathyroid-related peptide (PTHrP) compared with healthy foals. The magnitude of these differences will be negatively associated with survival.
Animals: Eighty-two septic, 40 sick nonseptic, and 24 healthy foals of ≤7 days were included.
Methods: Prospective, observational study. Blood was collected at initial examination for analysis. Foals with positive blood culture or sepsis score ≥14 were considered septic. Foals with disease other than sepsis and healthy foals were used as controls. Hormone concentrations were measured with validated immunoassays.
Results: Septic foals had decreased Ca2+ (5.6 versus 6.1 mg/dL, P < .01) and increased serum PTH (16.2 versus 3.2 pmol/L, P < .05), and phosphorus concentrations (7.1 versus 6.3 mg/dL, P < .01). No differences in serum Mg2+, PTHrP, and CT concentrations were found. Nonsurviving septic foals (n = 42/82) had higher PTH concentrations (41.1 versus 10.7 pmol/L, P < .01) than survivors (n = 40/82).
Conclusions and Clinical Importance: Septic foals were more likely to have disorders of calcium regulation compared with healthy foals, where hyperparathyroidemia was associated with nonsurvival.  相似文献   
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OBJECTIVE: To establish the range and cost of losses in Merino flocks in southern New South Wales during drought conditions by determining the cause of death, morbidity or wasting in adult sheep. DESIGN AND POPULATION: Pathological studies were performed on 392 dead or moribund adult sheep from 12 Ovine Johne's disease (OJD)-infected flocks during 2002 and a further 58 sheep culled due to wasting from one of these flocks in 2003. Flocks ranged between 3,500 and 20,000 sheep. METHOD: The most likely cause of death, morbidity or wasting was determined following consideration of the environment in which the animal was found, clinical and gross pathological findings, plus histopathology of tissues collected during necropsy. RESULTS: A most likely cause of death, morbidity or wasting was determined for 362 sheep in 2002 and 58 sheep in 2003. OJD contributed to the death of 250 sheep in 2002, and wasting of 48 sheep in 2003. Of the sheep that died or were euthanased due to other causes, malnutrition was a contributing factor in the death of 70 sheep (63%) in 2002 and 2 sheep (20%) in 2003. Losses were not evenly distributed across flocks, with 57% of mortalities caused by malnutrition in 2002 occurring in one flock. Malnutrition accounted for 18% of the annual cost of all deaths among adult sheep in 2002 with an average cost of $16,882 per farm. Losses not attributed to malnutrition included a range of infectious and non-infectious disorders. These included balanoposthitis, clostridial enterotoxaemia, cutaneous myiasis, endoparasitism, enteritis, intestinal adenocarcinoma, misadventure, peritonitis, periparturient death of ewes, photosensitisation, pneumonia, post-shearing stress and squamous cell carcinoma of the perineum. CONCLUSION: Almost one third of mortalities in OJD-infected flocks during drought were unrelated to OJD and could be reduced by improving nutritional and disease management practices. The importance of close supervision of the flock is highlighted so that early management intervention can be instituted, including the culling of cases of welfare concern.  相似文献   
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Auroras are caused by accelerated charged particles precipitating along magnetic field lines into a planetary atmosphere, the auroral brightness being roughly proportional to the precipitating particle energy flux. The Analyzer of Space Plasma and Energetic Atoms experiment on the Mars Express spacecraft has made a detailed study of acceleration processes on the nightside of Mars. We observed accelerated electrons and ions in the deep nightside high-altitude region of Mars that map geographically to interface/cleft regions associated with martian crustal magnetization regions. By integrating electron and ion acceleration energy down to the upper atmosphere, we saw energy fluxes in the range of 1 to 50 milliwatts per square meter per second. These conditions are similar to those producing bright discrete auroras above Earth. Discrete auroras at Mars are therefore expected to be associated with plasma acceleration in diverging magnetic flux tubes above crustal magnetization regions, the auroras being distributed geographically in a complex pattern by the many multipole magnetic field lines extending into space.  相似文献   
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A study of the real possibilities of carbohydrate profiles and chemometrics to characterize the botanical origin of honey from a single geographical area, the Province of Soria (Spain), is presented. To this end, 14 carbohydrates were quantified using high-performance liquid chromatography (HPLC) with pulsed amperometric detection (PAD) in 77 natural honeys, the botanical origins of which were ling, spike lavender, French lavender, thyme, forest, and multifloral. Principal component analysis has been employed as a first approach to characterize the honey samples analyzed, showing similarities between spike lavender and multifloral honeys. The best discrimination among groups is obtained when four canonical discriminant analyses were carried out sequentially, origin by origin, achieving an overall percentage of success of 90% following cross-validation.  相似文献   
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The objectives of this study were to describe pharmacokinetic and pharmacodynamic changes as a result of a single intravenous administration of magnesium sulfate (MgSO4) to healthy horses. MgSO4 is a magnesium salt that has been used to calm horses in equestrian competition and is difficult to regulate because magnesium is an essential constituent of all mammals. Six healthy adult female horses were administered a single intravenous dose of MgSO4 at 60 mg/kg of body weight over 5 min. Blood, urine, and cerebrospinal fluid (CSF) samples were collected, and cardiovascular parameters were monitored and echocardiograms performed at predetermined times. Noncompartmental pharmacokinetic analysis was applied to plasma concentrations of ionized magnesium (Mg2+). Objective data were analyzed using the Wilcoxon rank-sum test with p < .05 used as a determination for significance. Plasma concentrations of Mg2+ increased nearly fivefold, ionized calcium (Ca2+) decreased by nearly 10%, and the Ca2+ to Mg2+ ratio declined more than 3.5-fold and remained different than baseline until 24 hr (p < .05). Significant changes were seen with urinary fractional excretion of electrolytes, cardiovascular parameters, and echocardiographic measurements. No changes were detected in CSF electrolyte concentrations. The decrease in Ca2+ result of hypermagnesemia supports the interaction between these cations. Alterations detected in plasma electrolyte concentrations and urinary fractional excretion of electrolytes may serve as biomarkers for regulatory control for the nefarious administration of MgSO4.  相似文献   
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