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Veterinarians diagnose marijuana toxicity based on clinical signs and history, or in conjunction with an over-the-counter (OTC) human urine drug screen. With the legalization of recreational marijuana use becoming more prevalent in the United States, a more accurate test to aid in the diagnosis of canine marijuana toxicity is needed. We collected urine and serum samples from 19 dogs with confirmed or suspected marijuana toxicosis from multiple veterinary hospitals and analyzed them with a novel UPLC-MS/MS method. Calibrations from 0.1 to 100 ng/mL and QC materials were prepared. Samples were extracted, purified, and eluted with solid-phase extraction. Urine samples were tested with an OTC human urine drug screen. The limit of detection (LOD) and lower limit of quantification (LLOQ) ranges for marijuana metabolites in serum were 0.05–0.25 ng/mL and 0.1–0.5 ng/mL, respectively. In urine, the LOD and LLOQ ranges for the metabolites were 0.05–0.1 ng/mL and 0.1–0.5 ng/mL, respectively. In serum, median and range of metabolite concentrations (ng/mL) detected included: THC, 65.0 (0.14–160); 11-OH-Δ9-THC, 4.78 (1.15–17.8); 11-nor-9-carboxy-Δ9-THC, 2.18 (0.71–7.79); CBD, 0.28 (0.11–82.5); and THC-glucuronide, 2.05 (0.72–18.3). In the 19 urine samples, metabolite: creatinine (ng: mg) values detected included: THC, 0.22 (0.05–0.74); 11-OH-Δ9-THC, 0; 11-nor-9-carboxy-Δ9-THC, 1.32 (0.16–11.2); CBD, 0.19 (0.12–0.26); THC-COOH-glucuronide, 0.08 (0.04–0.11); and THC-glucuronide, 0.98 (0.25–10.7). Twenty of 21 urine samples tested negative for THC on the urine drug screen. All 19 serum samples contained quantifiable concentrations of THC using our novel UPLC-MS/MS method. Utilizing a UPLC-MS/MS method can be a useful aid in the diagnosis of marijuana toxicosis in dogs, whereas using an OTC human urine drug test is not a useful test for confirming marijuana exposure in dogs because of the low concentration of THC-COOH in urine.  相似文献   
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In situ digestion kinetics of neutral detergent insoluble nitrogen (NDIN) from alfalfa (Medicago sativa L.) harvested at one-tenth bloom and eastern gamagrass (Tripsacum dactyloides L.) harvested at the boot (GGB), anthesis (GGA), and physiological maturity (GGM) stages of growth were determined with nonlinear regression techniques. Whole-plant tissue and associated leaf and stem fractions were incubated in the ventral rumen simultaneously. On a wholeplant basis, potential extents of degradation were particularly high (> or =904 g/kg NDIN) for GGB and GGA, relative to those of GGM and alfalfa (772 and 658 g/kg NDIN, respectively). For all plant parts, degradation rates of NDIN were faster (P<.05) for alfalfa than for all gamagrass forages. Degradation rate of NDIN did not differ (P>.05) across maturities for any gamagrass tissue type. These results indicate 1) that phenological development and lignification do not limit the rate of NDIN degradation in gamagrass forages but do markedly limit the potential extent of NDIN availability and 2) that most of the NDIN in these forages is potentially available in the rumen and can contribute to the ruminal N supply. Our secondary objective was to compare estimates of N escaping ruminal degradation that were determined on the basis of NDIN degradation kinetics (NDIN method) with those determined traditionally, on the basis of total residual N. The NDIN method mathematically eliminates all neutral detergent soluble N from consideration as part of the pool of dietary N potentially escaping the rumen intact. Estimates of rumen escape nitrogen determined on the basis of degradation rates of NDIN were consistently less than corresponding estimates that were determined on the basis of total residual N. When ruminal escape N that was determined with the NDIN method was regressed on corresponding estimates with the total residual N method, the slopes of the regression lines were .53 and .66 for assumed passage rates of .02 and .06 h(-1), respectively. For the forages evaluated in this study, these results indicate that neutral detergent soluble N may make important contributions to the pool of N escaping ruminal degradation.  相似文献   
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Thirty-one female Syrian hamsters (Mesocricetus auratus) were inoculated intraperitoneally with a lethal dose of Burkholderia mallei (Budapest strain). Hamsters were killed postinoculation on days 0 through 6. Lesions were first noted in the spleens on postinoculation day 1, and in mediastinal and mesenteric lymph nodes, mediastinum, liver, and bone marrow on day 2. Lesions were present in the lung and submandibular lymph nodes on day 3, and in the brain on day 5. The characteristic histopathologic change was necrotizing pyogranulomatous inflammation, often with hemorrhage. Lesions indicative of impaired vascular perfusion, such as ischemia and infarction, were evident at the later time points. Pathologic changes generally increased in severity and distribution with time, and almost all tissues were ultimately affected. Our findings suggest that intraperitoneal bacteria were rapidly transported to mediastinal lymph nodes by transdiaphragmatic lymphatics and ultimately seeded other tissues hematogenously. The results of the study indicate that the Syrian hamster is a useful small animal model for glanders.  相似文献   
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A retrospective analysis of the metabolizable energy (ME) intake of privately owned pet cats from the authors’ nutrition consultation practice (years 2007–2011) was carried out to test whether current recommendations are suitable for pet cats. Data of 80 adult cats (median age: 9.0 years, median deviation from ideal weight: +22.5%, majority neutered) at maintenance were available. Six percentage of the cats were healthy and the others were affected by various chronic diseases. A standardized questionnaire was used, cat owners weighed cat and food. For ration calculation, the software Diet Check Munich? was used (ME prediction according to National Research Council, 2006: Nutrient Requirements of Dogs and Cats. National Academy Press, Washington, DC). Data were analysed for the factors deviation from ideal weight, breed, age, gender, disease and type of feeding [prepared food (dry, wet) vs. home‐made]. Over‐ or underweight were defined as ≥15% deviation from ideal body weight (BW) according to Kienzle and Moik (British Journal of Nutrition 2011, 106, Suppl 1: S113). Cat owner's estimation of ideal BW was higher than literature data from Kienzle and Moik (2011). Based on literature data, 26.3% of the pet cats were normal weight, 63.7% overweight and 10% underweight. The mean ME intake of all adult cats amounted to 0.40 ± 0.14 MJ/kg actual BW0.67 (n = 80). When the data were analysed according to normal, over‐ and underweight, there was a significant effect with normal weight cats eating 0.46 MJ/kg BW0.67. Underweight cats ate even more (0.49 MJ/kg BW0.67), whereas overweight cats ate considerably less (0.36 MJ/kg BW0.67). The other factors had no influence on ME intake of adult cats.  相似文献   
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The efficacy of two media, an Edward-type medium (EPJ) and a modified SP4-type medium (SP4-PS), were compared for primary isolation of Mycoplasma gallisepticum (MG) from commercial layer chickens (n = 58) vaccinated with the live F strain of MG. Three groups of chickens that differed in the interval after vaccinal exposure to the F strain (32, 41, and 102 weeks) were studied at necropsy. Mycoplasma isolation was attempted from the trachea, sinus, and cloaca using lavage and swab techniques but was successful only from the trachea and sinus. MG was isolated from 39 (8.4%) of 463 culture attempts from 58 tracheal inocula and 58 sinus inocula. Isolation of MG was successful more frequently using EPJ medium than SP4-PS medium, and isolation occurred more often from the sinus than from the trachea. Of the 58 chickens studied, 19 (33%) were shown by culture to be infected with MG. Isolation was successful only from 32- and 41-week post-vaccination exposure groups. However, all chickens studied were serologically positive for MG antibody by rapid-plate agglutination and hemagglutination-inhibition assays.  相似文献   
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