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31.
Leskovar A Coates JR Russell KE Walker MA Storts RW 《Journal of the American Animal Hospital Association》2003,39(3):306-310
A 2-year-old, spayed female, mixed-breed dog was presented for evaluation of a progressive asymmetric tetraparesis and cranial nerve deficits with a 3-week duration. Computed tomography showed a contrast-enhancing lesion along the left side of the junction of the medulla and the cervical spinal cord. An exploratory surgery determined the presence of an intramedullary lesion of the first cervical spinal cord segment. The mass was removed through a dorsal midline myelotomy. Microscopic examination identified a foreign body granuloma that contained a dense, anisotropic outer wall, supporting the conclusion that the foreign body was of plant origin. The dog recovered to a more improved ambulatory status than prior to surgery. 相似文献
32.
Studies have indicated variations in the degree of efficacy of certain commercial disinfectants used in poultry production facilities. We used an adequate method of in vitro testing to compare the efficacy of disinfectants while testing them in conditions similar to those of the poultry facilities. BioSentry 904, ethylenediaminetetracetic acid (EDTA)-Tris, and a combination of the two were tested by this method against five field isolates of Pseudomonas aeruginosa at 10(3), 10(6), and 10(9) colony-forming units (CFU)/ml. At the 10(9) CFU/ml concentration, most compounds failed to achieve a total kill with a contact time of 15 min. When tested at bacterial concentrations of 10(3) CFU/ml, the combination of EDTA-Tris mixed at a 1:1 ratio with BioSentry 904 killed the bacteria upon initial contact (< or = 0.05 min). This disinfectant mixture exhibited antagonistic, indifferent, or synergetic effects when exposed to different bacterial isolates at a concentration of 10(6) CFU/ml. 相似文献
33.
In mid-2000, a broiler chicken company in Alabama experienced high early mortality rates in chicks from two different hatcheries. Five isolates of Pseudomonas aeruginosa, obtained from these contaminated hatcheries and resulting broiler chicks with omphalitis, were selected to determine virulence of the bacteria. One-day-old specific-pathogen-free white leghorn chicks were placed into positive pressure isolation units (10 chicks per unit); feed and water were provided ad libitum. The five isolates of P. aeruginosa (1 x 10(1) or 1 x 10(1) colony-forming units/bird) were used to challenge two replicates of 10 chicks via yolk sac inoculation. Two control groups were injected with 0.1 ml of phosphate-buffered saline, and two groups received no treatment. Mortality was recorded daily, and the chicks that died were necropsied and liver and yolk sacs were cultured. After 14 days, the remaining chickens were euthanatized and necropsied. Bacterial isolates retrieved from liver and yolk sacs were identified by the API 20 NE typing system to confirm that they were the same as the challenge isolate. Virulence varied greatly among the isolates, resulting in mortality rates from 0 to 90%. The challenge isolates produced different and often distinctive postmortem lesion patterns. Antibiotic sensitivity tests showed that all five isolates were resistant to sulfisoxazole, ceftiofur, penicillin, lincomycin, bacitracin, oxytetracycline, erythromycin, naladixic acid, and tetracycline. The isolates varied in sensitivity to other antibiotics, but all isolates were sensitive to gentamicin. 相似文献
34.
Petersen AD Walker RD Bowman MM Schott HC Rosser EJ 《Journal of the American Animal Hospital Association》2002,38(5):407-413
Staphylococcus intermedius (S. intermedius) was isolated from 88.6% and 49.4% of skin and ear samples, respectively, during the years 1992 through 1997, and frequency of isolation remained unchanged. More than 95% of all S. intermedius isolates were susceptible to cephalothin and oxacillin, providing support for empirical treatment of canine skin and ear infections with cephalexin. Pseudomonas aeruginosa (P. aeruginosa) was isolated from 7.5% and 27.8% of skin and ear samples, respectively. The frequency of isolation from skin samples increased over the study period. Because of multidrug-resistant profiles for P. aeruginosa isolates, especially for ear isolates, empirical treatment of P. aeruginosa infections is not advisable. 相似文献
35.
36.
Horak IG Braack LE Fourie LJ Walker JB 《The Onderstepoort journal of veterinary research》2000,67(4):239-250
Ixodid ticks were collected from 104 wild carnivores belonging to 23 species in various nature reserves and on several farms in all nine provinces of South Africa. Seven feral cats in a nature reserve were also examined. Twenty-four tick species belonging to seven genera were recovered and identified. Amongst these ticks we consider the adults of Haemaphysalis leachi, Haemaphysalis spinulosa, Haemaphysalis zumpti, Ixodes rubicundus, Rhipicentor nuttalli, Rhipicephalus simus and Rhipicephalus turanicus to be true parasites of wild carnivores. Although numerous adult Rhipicephalus appendiculatus and Rhipicephalus zambeziensis were collected from some lions these were either sick or old animals. The immature stages of seven species regularly utilized wild carnivores as hosts on an opportunistic basis. 相似文献
37.
S L Lodge-Ivey K Walker T Fleischmann J E True A M Craig 《Journal of veterinary diagnostic investigation》2006,18(4):369-374
Ergot alkaloids present in endophyte-infected tall fescue induce fescue toxicosis in livestock consuming the plant. The lysergic acid (LA) ring structure is a common moiety among the ergot alkaloids. Little is known about the bioavailability of LA because of limitations in available analytical protocols. Thus, a high-performance liquid chromatography procedure was developed to analyze biological matrices for LA. The biological matrices of interest were tall fescue straw and seed, and ruminant feces, urine, and ruminal fluid. Lysergic acid was added to each matrix at a high (150 ng/ml) or low (30 ng/ml) level. Using the high-level addition, the greatest recovery of LA was obtained from ruminal fluid, feces, and urine (P < 0.05), with an average 85.1% recovered. At the low level, a greater recovery of added LA was observed in the ruminal fluid, urine, and feces (82.1%; P < 0.05) than that in the other 2 matrices (62.6%). The limit of quantitation (LOQ) in ruminal fluid and urine was 5.5 and 18.4 ng/ml, respectively. Seed, straw, and feces had higher LOQ (24.2, 14.5, and 36.0 ng/g, respectively). Limit of detection (LOD) was 1.64, 10.80, 4.35, 5.52, and 7.26 ng/g for ruminal fluid, feces, urine, seed, and straw, respectively. To test the assay in vivo, samples of ruminal fluid and urine were collected from steers consuming a diet containing 400 ng of ergovaline/g and 30 ng of LA/g. All matrices sampled resulted in levels above the LOD and LOQ for the assay, indicating that this assay is sufficiently sensitive for use in assessing the bioavailability of LA. 相似文献
38.
39.
Treating elderly pets and maximising your practice returns will be in focus at this year's AVA Annual Conference. The Scientific Organising Committee is delighted that such distinguished international and local speakers have agreed to give presentations in the Small Animal (Geriatric Medicine and Surgery) and Practice Management streams at the conference.
The AVA Conference will be at Hobart's Wrest Point Conference Centre from May 21–26, 2006. To see the full program and to register online visit www.ava.com.au/avaconference. 相似文献
The AVA Conference will be at Hobart's Wrest Point Conference Centre from May 21–26, 2006. To see the full program and to register online visit www.ava.com.au/avaconference. 相似文献
40.
Stephen M.G. Duff Yun-Chia Sophia Chen Gopichand Yalamanchili Dan M. Walker Edward A. Boyd Christopher J. Yarnold 《Pesticide biochemistry and physiology》2007,88(1):1-13
The carboxyterminal processing protease of D1 protein (CtpA) is predicted to be an excellent target for the discovery of a general broad-spectrum herbicide. Directed and random screening of compounds against recombinant spinach CtpA (rCtpA) has led to the discovery of five different chemical classes of inhibitors. Lead compounds from each inhibitor class were investigated for their in vitro effects on the activities of both recombinant and native spinach CtpA. All of the lead compounds have Ki values of less than 50 μM when tested against rCtpA, and all except one showed competitive inhibition. Results from partially purified native CtpA from spinach were similar to those from the recombinant form of the enzyme, thus validating the use of rCtpA in the inhibitor screen. Compounds from three of the classes of CtpA inhibitors show in vivo herbicidal activity against Arabidopsis thaliana when applied either by addition to growth media or by spraying the leaves. Transgenic Arabidopsis plants which over-express CtpA showed greater resistance to the compounds than wild-type plants providing evidence that these inhibitors are directly acting against CtpA. 相似文献