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91.
Objective – To determine the incidence rate and prognostic significance of ionized hypocalcemia (iHCa) among septic dogs. Design – Retrospective study Setting – Veterinary teaching hospital Animals – Fifty‐eight septic dogs that were presented to Cornell University Hospital for Animals between January 2006 and December 2007. Procedure – Cases were diagnosed with sepsis if they exhibited 2 or more criteria of the systemic inflammatory response syndrome with a concurrent documented infectious focus. Cases were excluded if diagnosed with a concurrent illness reportedly associated with calcium derangements. Lowest, mean, and highest blood ionized calcium concentrations were recorded and statistically analyzed for an association with morbidity, as measured by duration of hospitalization and number of blood product transfusions, and outcome. In addition, the incidence rate of iHCa was recorded. Results – Of the 58 cases included in this study, iHCa was documented in 4 of 6 (67%) patients that died, 5 of 19 (26%) euthanized patients and 5 of 33 (15%) patients that survived to discharge, with an overall incidence of 24%. Dogs that died during hospitalization had more severe iHCa than patients that were discharged or euthanized as well as significantly lower mean ionized calcium concentrations than patients who were discharged. Severity of iHCa was also associated with a longer duration of hospitalization. The highest ionized calcium concentration was not associated with outcome. Conclusion and Clinical Relevance – This study is the first to document the incidence of iHCa among septic dogs. Because both low mean ionized calcium and the lowest documented ionized calcium concentration are associated with poor outcome, it is likely that both the severity and duration of hypocalcemia are important in these patients. Further prospective studies investigating the prognostic significance, etiology and treatment of iHCa among septic veterinary patients are needed to better understand its role in sepsis.  相似文献   
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Understanding functional connectivity is critical for several issues in ecology and conservation. When animals actively search for habitat across landscapes, their perceptual range of habitats can profoundly influence connectivity. Nonetheless, conceptual development and estimation of perceptual ranges and their influence on connectivity have been limited. Signal detection theory (SDT) has a long tradition in several disciplines to address the problem of detecting stimuli in noisy and uncertain environments. SDT is particularly useful for understanding perceptual ranges because it acknowledges uncertainty in the detection process and distinguishes between two key parameters that have previously been confounded when interpreting the perceptual range of animals: signal detectability and response bias of individuals. Here we extend SDT to the concept of perceptual range, provide approaches for estimating patch detectability and response bias, and apply this framework to interpreting the perceptual range of cactus bugs (Chelinidea vittiger). We find that signal detectability of habitat by C. vittiger, and thus their perceptual range, is between 1 and 2 m, based on generalized linear models aimed at estimating signal detection parameters. SDT provides new insights into perceptual ranges and functional connectivity, which may help understand intra and interspecific variation in animal responses to modified landscapes.  相似文献   
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Austral bracken Pteridium esculentum contains three unstable norsesquiterpene glycosides: ptaquiloside, ptesculentoside, and caudatoside, in variable proportions. The concentration of each of the glycosides was determined in this study as their respective degradation products, pterosin B, pterosin G and pterosin A, by HPLC-UV analysis. Samples of P. esculentum collected from six sites in eastern Australia contained up to 17 mg of total glycoside/g DW, with both ptaquiloside and ptesculentoside present as major components accompanied by smaller amounts of caudatoside. Ratios of ptaquiloside to ptesculentoside varied from 1:3 to 4:3, but in all Australian samples ptesculentoside was a significant component. This profile differed substantially from that of P. esculentum from New Zealand, which contained only small amounts of both ptesculentoside and caudatoside, with ptaquiloside as the dominant component. A similar profile with ptaquiloside as the dominant glycoside was obtained for Pteridium aquilinum subsp. wightianum (previously P. revolutum ) from northern Queensland and also P. aquilinum from European sources. Ptesculentoside has chemical reactivity similar to that of ptaquiloside and presumably biological activity similar to that of this potent carcinogen. The presence of this additional reactive glycoside in Australian P. esculentum implies greater toxicity for consuming animals than previously estimated from ptaquiloside content alone.  相似文献   
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Chlamydia psittaci was detected by PCR in the lung and equine foetal membranes of two aborted equine foetuses and one weak foal from two different studs in Victoria, Australia. The abortions occurred in September 2019 in two mares sharing a paddock northeast of Melbourne. The weak foal was born in October 2019 in a similar geographical region and died soon after birth despite receiving veterinary care. The detection of C. psittaci DNA in the lung and equine foetal membranes of the aborted or weak foals and the absence of any other factors that are commonly associated with abortion or neonatal death suggest that this pathogen may be the cause of the reproductive loss. The detection of C. psittaci in these cases is consistent with the recent detection of C. psittaci in association with equine abortion in New South Wales. These cases in Victoria show that C. psittaci, and the zoonotic risk it poses, should be considered in association with equine reproductive loss in other areas of Australia.  相似文献   
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Insufficient phosphorus (P) availability decreases the yield of Zea mays, particularly for sweet corn crops grown in cool environments. This research examined the mechanisms of yield reductions with initial emphasis on canopy expansion processes that affect the interception of solar radiation. Experiments in two consecutive seasons (2001/2002 and 2002/2003) were grown at a low P site (Olsen P = 6 μg ml−1) at Lincoln, New Zealand. Each experiment contained five rates of P application. In 2001/2002 rates of 0, 50, 100, 150, or 200 kg P ha−1 were applied. In 2002/2003 an additional 0, 0, 10, 20 or 40 kg P ha−1 was applied to the same plots producing total P treatments of 0, 50, 110, 170 or 240 kg P ha−1 summed over the two seasons.When P availability was limited (0 or 50 kg P ha−1) the rates of leaf tip and fully expanded leaf appearance were slower in both seasons. Phyllochrons (°Cd leaf tip−1) were 5 °Cd longer in crops that received 0 kg P ha−1 than those fertilised with ≥100 kg P ha−1. The area of individual leaves was also reduced by low P inputs but the ranking of leaf area by main stem leaf position was conservative. The leaf area of the largest leaf of the unfertilised crops was at least 22% less than the maximum measured leaf area in both seasons. In contrast, P fertiliser application had no effect on leaf senescence.The rate of leaf appearance per plant, individual leaf area and plant population were integrated to calculate green leaf area index (GLAI) and to estimate accumulated radiation interception (RIcum) for these crops. The total RIcum throughout the season in the unfertilised crops was 12–28% less than for those crops that received ≥100 kg P ha−1 in both seasons. This difference partly explained the differences in crop biomass production in response to P availability. A sensitivity analysis showed that RIcum was equally sensitive to changes of the rate of leaf appearance and the area of individual leaves in response to P supply. Both processes need to be incorporated in mechanistic models of P effects on Z. mays which can be used to design efficient P fertiliser strategies.  相似文献   
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