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排序方式: 共有2336条查询结果,搜索用时 281 毫秒
91.
Chapman PS Green C Main JP Taylor PM Cunningham FM Cook AJ Marr CM 《The Veterinary record》2000,146(4):91-95
A total of 1235 tracheal aspirates taken from 724 thoroughbreds in race training, aged from two to 10 years, were examined cytologically and bacteriologically. An inflammation scoring system on a scale of 0 to 9 was devised to allow the severity of lower airway disease to be assessed from the cytological results. The inflammation scores were closely related to the isolation of bacteria (P<0.001), and the most common bacterial isolates were Streptococcus zooepidemicus, Streptococcus pneumoniae and Pasteurella/Actinobacillus-like species. Lower airway disease was less common in older horses (P = 0.031), and the groups at highest risk were the two- and four-year-olds. Lower airway inflammation was more common in the four-year-olds at National Hunt yards than in the four-year-olds at flat racing yards (P = 0.040, odds ratio = 3.80). 相似文献
92.
Three groups of five parasite-naive calves were used. The treatments were: (a) Group 1 calves were weighed on Day 0 and injected with doramectin at 200 microg/kg. From Day 1 to 19 they were dosed orally with 2000 infective larvae of Dictyocaulus viviparus. On Day 28 they were again injected with doramectin, and infected with D. viviparus larvae from Days 33 to 41. They were then left untreated until Day 81 when they were infected with 20 infective larvae of D. viviparus per kg body weight. They were killed on Day 110 and lungworms were counted; (b) Group 2 calves were immunised with oral lungworm vaccine on Days 0 and 28, and infected and slaughtered as Group 1 on Days 81 and 110, respectively; (c) Group 3 calves acted as infection controls. Blood samples were taken at Days 0, 21, 49, 77 and 110 for antibody tests to D. viviparus. At autopsy there were no significant differences between the number of lungworms from Groups 1 and 2 (Means 17.4 and 31.3, respectively); Group 1 had significantly less value than Group 3 (Mean 228) (p < 0.05). Increased antibody titres to the larval sheath of the infective larvae were observed from Groups 1 and 2, showing that the larvae in Group 1 had penetrated the intestine before being killed by the circulating anthelmintic. This experiment shows that if calves are exposed to infective larvae while under systemic endectocide cover, an immune reaction is stimulated. 相似文献
93.
Buergelt CD Layton AW Ginn PE Taylor M King JM Habecker PL Mauldin E Whitlock R Rossiter C Collins MT 《Veterinary pathology》2000,37(5):428-438
Gross and histopathologic examinations were performed on 70 North American bison (Bison bison) from a Mycobacterium avium paratuberculosis culture-positive herd. The bison examined were part of a breeding herd totaling 2,800 animals. Eight of 70 (11%) animals had gross findings of intestinal mucosal thickening, and 16 of 70 (23%) of the animals had enlarged mesenteric lymph nodes. Histologic lesions compatible with Johne's disease were diagnosed in 30 of 70 (43%) bison on the basis of the demonstration of noncaseating granulomatous inflammatory infiltrates and of one or more acid-fast bacilli characteristic of Mycobacterium avium paratuberculosis. A suspicious diagnosis of Johne's disease was obtained in 11 of 70 (16%) bison on the basis of the observation of noncaseating granulomatous inflammatory infiltrates without demonstrable acid-fast bacteria. Twenty-nine of 70 (41%) animals were assessed as histologically paratuberculosis free. Histologic results were compared to Johne's disease tests such as culture, serology, and polymerase chain reaction, which were performed on some of the cohort animals. 相似文献
94.
K. H. Taylor A. N. Smith M. Higginbotham D. D. Schwartz D. M. Carpenter E. M. Whitley 《Veterinary and comparative oncology》2007,5(4):208-218
Serum, plasma and tissue expression of vascular endothelial growth factor (VEGF) was measured in 20 dogs previously diagnosed histologically with oral melanoma. The concentrations of VEGF in serum and plasma were significantly higher in dogs with melanoma than in a control population (P ≤ 0.002). Concentrations of VEGF in the serum and plasma of dogs with melanoma were highly correlated (r = 0.867). Ninety‐five per cent of melanoma tissues expressed VEGF. Two staining patterns were detected: diffuse and granular cytoplasmic staining. High blood concentrations of VEGF were correlated to a shorter survival time in dogs receiving definitive therapy (P = 0.002). Survival times were significantly longer in dogs receiving definitive therapy versus palliative therapy (median 496 versus 97 days, P = 0.007). Blood concentrations of VEGF were associated with stage (P < 0.05). Dogs with oral melanoma have increased serum, plasma and tissue concentrations of VEGF. Increased expression of VEGF may be a reasonable target for future therapy of canine oral melanoma. 相似文献
95.
胃炎和胃溃疡是生长肥育猪和母猪的一种常见、但很少被诊断出的疾病,它可引发诸多的问题:从导致肥育猪产生进攻性行为、生产性能受挫,直至死亡。而海洋矿物质或许可以解决上述问题。 相似文献
96.
Simulation study of the competitive ability of erect, semi-erect and prostrate cowpea (Vigna unguiculata) genotypes 总被引:1,自引:1,他引:1
Ecophysiological simulation models provide a quantitative method to predict the effects of management practices, plant characteristics and environmental factors on crop and weed growth and competition. The INTERCOM interplant competition model was parameterised, calibrated by monoculture data for three cowpea (Vigna unguiculata) genotypes that differed in growth habit, common sunflower (Helianthus annuus) and common purslane (Portulaca oleracea), and used to simulate competition of cowpea cover crops with sunflower or purslane. The simulation results were compared with observations from field competition experiments in 2003 and 2004. INTERCOM more accurately simulated actual field data for the competition of cowpea genotypes and sunflower than companion field experiments for the competition of cowpea and purslane. The validated simulation model of cowpea and sunflower at two densities was used to study the effects of cowpea growth habit on final biomass production of cowpea and sunflower. The model suggested that erect growth habit was more competitive than semi‐erect and prostrate growth habit, when cowpea genotypes were grown with sunflower. Cowpea leaf area distribution was important to higher cowpea biomass production, while cowpea height growth was important to reduce sunflower biomass. Our simulation approach is suggested as a method for crop breeders to gauge the likely success of selection for competitive crops before undertaking expensive long‐term breeding experiments. 相似文献
97.
T. V. Balmer D. Irvine R. S. Jones † M. J. Roberts † L. Sungsby ‡ P. M. Taylor A. E. Waterman ‡ C. Waters § 《The Journal of small animal practice》1998,39(4):158-164
The postoperative analgesia and sedation in cats given carprofen (4·0 mg/kg bodyweight by subcutaneous injection preoperatively) was compared to that in cats given pethidine (3·3 mg/kg bodyweight by intramuscular injection postoperatively) in a controlled, randomised, blinded, multicentre clinical trial. Further dosing with the particular analgesic was allowed if a cat was exhibiting unacceptable pain. In total, 57 carprofen cases and 59 pethidine cases were evaluated. Significantly fewer cats in the carprofen group required additional doses of analgesic, and mean pain scores were significantly lower from four hours after ovariohysterectomy, and at 18 to 24 hours after castration, compared to the pethidine group. In conclusion, carprofen provided as good a level of postoperative analgesia as pethidine, but of a longer duration (at least 24 hours) and was well tolerated. It thus provides an option for 'pre-emptive analgesia' in cats about to undergo surgery. 相似文献
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100.
Abstract— The daily riboflavin excretion of five adult cats has been studied for periods ranging from 7 to 11 days. The cats were housed in metabolism cages and were provided with a diet of cooked rabbit meat, wholemeal bread and water. The total amount of riboflavin excreted does not appear to be related to the dietary intake. The concentration of riboflavin in the urine does appear to be characteristic for a given cat under our experimental conditions.
Résumé— L'excrétion quotidienne de riboflavine chez cinq chats adultes a étéétudié pendant des périodes allant de 7 à 11 jours. Les chats étaient casés dans des cages à métabolisme et recevaient un régime de viande de lapin cuite, de pain entier et d'eau. La quantité totale de riboflavine excrétée ne semble pas être en rapport avec la quantité ingérée. Dans les conditions expérimentales que nous avons utilisées la concentration urinaire de riboflavine parait caractéristique pour un chat donné.
Zusammenfassung— In einer von 7 bis zu 11 Tagen reichenden Zeitspanne wurde untersucht, wieviel Laktoflavin fünf ausgewachsene Katzen täglich ausscheiden. Die Katzen wurden in Käfigen untergebracht, in denen der Stoffwechsel ständig überprüft werden kann, und sie wurden mit einer aus gekochtem Kaninchenfleisch, Vollkornbrot und Wasser bestehenden Diät gefüttert. Die Gesamt-menge des ausgeschiedenen Laktoflavins scheint in keiner Beziehung zu der Nahrungsaufnahme zu stehen. Die Konzentration des Laktoflavin im Urin scheint für eine unter unseren Versuchs-bedingungen stehende Katze charakteristisch zu sein. 相似文献
Résumé— L'excrétion quotidienne de riboflavine chez cinq chats adultes a étéétudié pendant des périodes allant de 7 à 11 jours. Les chats étaient casés dans des cages à métabolisme et recevaient un régime de viande de lapin cuite, de pain entier et d'eau. La quantité totale de riboflavine excrétée ne semble pas être en rapport avec la quantité ingérée. Dans les conditions expérimentales que nous avons utilisées la concentration urinaire de riboflavine parait caractéristique pour un chat donné.
Zusammenfassung— In einer von 7 bis zu 11 Tagen reichenden Zeitspanne wurde untersucht, wieviel Laktoflavin fünf ausgewachsene Katzen täglich ausscheiden. Die Katzen wurden in Käfigen untergebracht, in denen der Stoffwechsel ständig überprüft werden kann, und sie wurden mit einer aus gekochtem Kaninchenfleisch, Vollkornbrot und Wasser bestehenden Diät gefüttert. Die Gesamt-menge des ausgeschiedenen Laktoflavins scheint in keiner Beziehung zu der Nahrungsaufnahme zu stehen. Die Konzentration des Laktoflavin im Urin scheint für eine unter unseren Versuchs-bedingungen stehende Katze charakteristisch zu sein. 相似文献