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1.
A 4-month-old male Old English Sheepdog was presented for evaluation of a raw meat-based homemade diet after a 1-month history of progressive lameness. Marked dietary deficiencies were detected, which included calcium, phosphorus and vitamin D. Hypovitaminosis D and hypocalcaemia were diagnosed by serum analysis. Evidence of severe diffuse osteopenia was noted on survey radiographs. Dual-energy X-ray absorptiometry (DEXA) was used to quantify bone mineral content and density and compare to published reference ranges. The puppy's initial bone mineralization was markedly subnormal, with bone mineral density 66% lower than expected, and bone mineral content 40% lower than expected. Subsequent DEXA scans were performed at intervals during the puppy's recovery to document the rate of bone re-mineralization and guide therapeutic recommendations. Marked improvement was achieved within 4 months through exercise control and feeding of a diet appropriately formulated for large breed puppy growth and development. This report reinforces the necessity of thorough dietary history and highlights the potential for malnutrition in pets fed homemade and raw meat-based diets. Use of DEXA has rarely been reported in clinical cases, yet can be a valuable tool for diagnosing and monitoring cases with abnormal bone mineralization. Further studies using DEXA to track bone mineralization in healthy puppies are encouraged to develop a more robust reference range of bone mineralization in growing dogs of varying sizes, weights and ages.  相似文献   
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Four Morgan mares and five Morgan geldings ranging in age from 5- to 12-years-old were fitted with Global Positioning System units to determine if season has an influence on travel pattern. Body and hoof growth measurements were obtained so that the influence of season on body condition and hoof growth could be determined. Waist and heart circumference, cresty neck score, and body condition score were determined in each season. The ambient temperature and precipitation was recorded for each season. Waist circumference was the greatest (P < .05) in the spring and summer and the least in the fall and winter. Hoof growth was the greatest (P < .05) in the fall and the least in the winter. The front and rear hooves grew at similar rates in all horses. Hoof growth in geldings and mares were also similar. The average distances traveled were similar across seasons; however, the horse did numerically travel more in the spring and summer compared with the fall and winter. The range of the travel pattern was influenced by season with the horses traveling significantly less in the winter, although the average travel distances were similar. In conclusion, season in temperate zones will influence body condition, hoof growth, and pattern of travel, but the total distance traveled will be similar. Further research needs to be conducted to determine the influence of season on hoof growth and travel patterns.  相似文献   
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It is well established that vegetables and fruit (VF) contain antioxidant phytochemicals. Consequently, it is expected that individuals who consume diets with a high content of VF should be better protected against oxidative cellular damage than individuals who do not, but not all data support this assumption. The objective of this study was to identify possible explanations for this conundrum. The effects of two diets that differed in VF content on markers of oxidative damage were studied. Sixty-four women participated in a 14-day dietary intervention. Subjects consumed on average either 3.6 or 12.1 servings of VF per day. The primary end points assessed were 8-hydroxy-2-deoxyguanosine (8-oxo-dG) in peripheral lymphocyte DNA and 8-isoprostaglandin F-2alpha (8-iso-PGF2alpha) excreted in urine. Subjects consuming the high versus low VF diet had lower concentrations of 8-oxo-dG (p < 0.01) and of 8-iso-PGF2alpha (p < 0.01). However, the reduction in oxidative end points by high VF was not uniform. Rather, an antioxidant effect was observed primarily in individuals whose oxidative end points at baseline were above the median for the study population. Using change in plasma carotenoids (end point minus baseline measurements) as an index of phytochemical intake, the reduction in oxidative markers was inversely proportional to change in plasma carotenoids; this effect was stronger for lipid peroxidation (p < 0.01) than DNA oxidation (p < 0.05). These findings imply that increasing exogenous antioxidant exposure may primarily benefit individuals with elevated levels of oxidative stress. Null findings do not necessarily indicate that an antioxidant compound lacks in vivo activity.  相似文献   
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Context

With underrepresentation of habitats in publicly protected areas, attention has focused on the function of alternative land conservation mechanisms. Private conservation easements (CEs) have proliferated in the United States, yet assessing landscape-level function is confounded by varying extent, resolution, and temporal scale.

Objectives

We developed and tested an assessment tool to evaluate interacting spatial, social, and environmental attributes of easements relative to the degree of human modification (HM). We hypothesized that on both private and public conservation properties HM would be lower than on non-conserved parcels, and that for fine-scale features (most CEs), the level of HM would be driven by the variables used to create the coarser scale HM measure.

Methods

Variation in HM between private, public, and non-conserved was tested via pairwise parcel sampling. Composition was evaluated using multiple geographic bounds and edge characteristics. We assessed both environmental and social predictors using multinomial logistic regression.

Results

Privately conserved lands did not differ significantly from non-conserved lands. Publicly conserved lands had lower HM than both privately conserved and non-conserved lands. Edge contrast was similar between private and matched non-conserved patches. The level of HM was not driven by distance to roads, or by elevation in this mixed-use setting.

Conclusions

Variation in tests for differences, land characteristics, and HM variables confirmed the significantly lower HM of publicly protected lands, and opens the question as to naturalness of easements in some contexts. CEs in this location may be representative of the mixed rural-forested landscape instead of more natural land cover.

  相似文献   
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An 18-year-old, grey, Thoroughbred Cross gelding was referred to the Cummings School of Veterinary Medicine at Tufts University following a 3-week history of low-grade fever of unknown origin, distal limb swelling, and weight loss. Clinical examination identified a few black, round, smooth nodules along the ventral aspect of the proximal tail. Transabdominal ultrasound showed a markedly enlarged heterogenous spleen, hyperechoic liver nodules, and evidence of peritonitis with fibrin deposition. A mature neutrophilia was noted on complete blood count with variable numbers of phagocytized granules within neutrophils. The granules did not stain with Perl's Prussian blue, and were intensely positive when stained with Fontana-Mason, consistent with melanin. On necropsy, the spleen occupied approximately one-third of the abdominal cavity and was diffusely firm with abundant black pigment on cut section. The medullary space of the 18th thoracic vertebra was also diffusely blackened. The splenic, mediastinal, and tracheobronchial lymph nodes were five times the normal size and diffusely pigmented. The final anatomic diagnosis was disseminated malignant melanoma with extensive splenic involvement and hemolymphatic and vascular neoplastic dissemination. To the authors' knowledge, this is the first full report to identify circulating neutrophils containing phagocytized melanin granules, which confirmed an antemortem diagnosis of disseminated melanoma.  相似文献   
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Cyclosporine is a powerful T‐cell inhibitor used in the treatment of immune‐mediated and inflammatory diseases in the dog. There is limited information on how to best monitor patients on cyclosporine therapy. Currently, pharmacokinetic and pharmacodynamic assays are available. Pharmacokinetic assays that measure the concentration of cyclosporine in the blood are used to assess if an appropriate drug concentration has been achieved; however, target blood drug concentrations have not been shown to reliably correlate with suppression of T‐cell function in the dog. In human transplant recipients, therapeutic drug monitoring has shifted to include pharmacodynamic‐based monitoring. Our laboratory has validated a RT‐qPCR assay to measure the pharmacodynamic effects of cyclosporine in the dog. In this study, activated T‐cell expression of IL‐2 and IFN‐γ was measured using RT‐qPCR daily for 7 consecutive days in 8 healthy Walker hounds receiving oral cyclosporine at a dosage of 10 mg/kg every 12 hr. Cytokine production was found to be markedly decreased within 24 hr after the initiation of cyclosporine and remained significantly decreased for the duration of the project. Based on these results, cyclosporine causes a rapid drop in T‐cell cytokine production that is sustained with continued dosing in healthy dogs. Although performed in healthy dogs, this study demonstrated a marked decrease in cytokine suppression within 24 hr of drug administration, suggesting that pharmacodynamic monitoring of cyclosporine's effects on T cells could be considered within several days of commencing therapy in dogs suffering from life‐threatening immune‐mediated disorders.  相似文献   
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