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991.
M. S. McNulty 《British poultry science》1997,38(1):7-13
This paper uses background information about chicken anaemia virus as a guide to how the study and control of virus diseases of poultry may develop in the future. It is predicted that ‘new’ viruses will be discovered in poultry, many of which will be difficult to grow in vitro and whose pathogenicity may appear uncertain. When new diseases/syndromes arise in the future, it should be a priority activity to define their pathology. The limitations of currently available virus diagnostic methods are highlighted. The possibility of vaccinating against economically important subclinical disease is discussed, as is the use of recently developed technologies in differentiating virus strains and in developing new vaccines. 相似文献
992.
993.
OBJECTIVE: To study the role of lectures from the perspective of staff and students involved in the veterinary course at The University of Queensland. METHODS: The Nominal Group Technique of Delbecq et al, which provides the maximum opportunity for group members to put forward points, was used to help develop a questionnaire which was completed by 351 students (a response rate of 84%) and 35 staff (76%) from the five years of the veterinary course, and was analysed using the SAS System for Windows. RESULTS: Almost all the staff and students agreed that lectures should fulfil many roles including stimulating and motivating students and encouraging them to think, as well as presenting ideas and concepts and an indication of the structure and relevance of the material. They should provide a guide for effective deep learning, but not encourage rote (or superficial) learning. A smaller percentage of staff and even fewer students agreed that lectures did fulfil these roles, especially those directed at encouraging students to look beyond simple memorisation of facts. The perceived disparity between reality and the ideal was greater amongst the older, clinical students than amongst their more junior colleagues. CONCLUSIONS: The focus of attention in lectures needs to change from the superficial, rote learning of information to deep, active learning directed at using information to solve problems that are perceived by the students to be relevant. If done in a stimulating and interesting way, this should develop skills in reasoning and critical analysis as well as providing a framework for storage and recall. It should also increase the motivation towards learning both during the veterinary course, and over the professional lifetime. Furthermore, the place of the lecture in veterinary education needs to be reassessed regularly in the face of newly-emerging educational technology. 相似文献
994.
Hill PB Auxilia ST Munro E Genovese L Silkstone MA Kirby B 《The Journal of small animal practice》2000,41(11):519-523
A nine-year-old, neutered female Shetland sheepdog was presented with crusted, ulcerative skin lesions affecting the footpads, commissures of the lips and the lateral canthi of the eyes. Histopathological examination of skin biopsies revealed changes consistent with superficial necrolytic dermatitis and biochemical analysis demonstrated elevated liver enzymes. Abdominal radiography revealed a small liver which, on ultrasonography, appeared diffusely mottled and showed changes suggestive of periportal fibrosis. On exploratory laparotomy, the pancreas appeared normal, but the liver was small and had multiple nodules throughout the parenchyma. This appearance was confirmed as cirrhosis on histopathological examination. The dog was placed on a hepatic support diet and treated with colchicine, essential fatty acid supplementation and raw egg yolks. After four weeks, the skin lesions had resolved and the dog remained free of clinical signs over a 22-month follow-up period. 相似文献
995.
Coolman BR Ehrhart N Marretta SM 《Journal of the American Animal Hospital Association》2000,36(6):542-547
A technique was developed for closure of gastrotomy and enterotomy incisions using disposable skin staples. The technique was used successfully in three dogs with gastrointestinal linear foreign bodies that required a gastrotomy and one or more enterotomies. The method allows for secure closure of gastrointestinal incisions and minimizes the surgical time in patients requiring multiple gastrointestinal incisions. 相似文献
996.
Cryptosporidial oocyst shedding was detected in a 2.5-year-old Quarterhorse stallion with diarrhoea. Based on the detection of cryptosporidial oocysts, and the absence of other aetiological agents or enteropathogens, cryptosporidiosis was presumptively diagnosed. This case was unusual because cryptosporidial oocyst shedding is primarily found in some immunocompromised or immature horses, and has not been reported in healthy mature horses. 相似文献
997.
OBJECTIVE: To determine efficacy of intratesticular injection of glycerol as a means to sterilize dogs. ANIMALS: Six 2- to 4-year-old sexually intact male dogs. PROCEDURE: Testicular volume, serum testosterone concentration, and number of sperm in ejaculate were determined before and at weekly intervals for 12 weeks following intratesticular injection of a 70% glycerol solution (1 ml/testis). Testicular tissue specimens for histologic evaluation were obtained 4, 8, and 12 weeks following injection. RESULTS: Number of sperm in ejaculate following glycerol injection was not significantly different from number before injection. Compared with preinjection values, serum testosterone concentrations were significantly less 5, 9, and 10 weeks following injection, although libido and ejaculate characteristics were unchanged. Testicular swelling was evident 24 to 48 hours following injection, and testicular volume decreased starting on week 5 following treatment. Seminiferous tubules and evidence of normal spermatogenesis were detected in testicular biopsy specimens obtained from all dogs 12 weeks following injection. CONCLUSION AND CLINICAL RELEVANCE: Intratesticular injection of a 70% glycerol solution did not result in azoospermia and sterility in dogs. 相似文献
998.
Matsuo K Tada T Nonaka N Oku Y Kamiya M 《The Japanese journal of veterinary research》2000,47(3-4):145-149
This study revealed the dose dependency of prednisolone tertiary-butylacetate (PTBA) treatment on the establishment of Echinococcus multilocularis in the small intestine of Mongolian gerbil (Meriones unguiculatus) and that some of the physiological parameters of host were correlated with the doses of PTBA and establishment of the worm. Twenty Mongolian gerbils were divided into 5 groups, according to the doses of PTBA; 0 mg, 0.5 mg, 2 mg, 5 mg and 10 mg per head. All animals were injected intraperitoneally with PTBA every other day from 6 days before to 6 days after infection. Doses of PTBA and the number of worms recovered at 7 days post-infection showed a positive correlation (r = 0.929, P < 0.0001). The increase of total protein (TP) and the decrease of the percentage of lymphocytes in the peripheral leukocytes were dependent on doses of PTBA (TP: r = 0.811, P < 0.0001, percentage of lymphocyte: r = -0.92, P < 0.0001). The TP and the percentage of lymphocyte also correlated with the number of worms recovered (TP: r = 0.617, P = 0.0049; percentage of lymphocyte: r = -0.800, P < 0.0001). 相似文献
999.
de B Welchman D Ainsworth HL Pennycott TW MacKenzie G Wood AM 《The Veterinary record》2000,147(4):93-97
Between 1995 and 1997 a neurological condition in pheasant poults from 24 sites in England and Scotland was investigated. Affected birds showed varying degrees of ataxia and incoordinated movements and, in severe cases, recumbency, but generally remained alert with their heads held upright. The condition characteristically affected poults from seven weeks of age and the incidence on any one site was low. No significant bacteria were isolated consistently from brain tissue. The condition was characterised histologically by a non-suppurative meningoencephalitis, in which lesions were found predominantly in the cerebellum in 61 of 81 samples examined (75.3 per cent). A non-suppurative myelitis was recorded in 16 of 20 spinal cords examined. No lesions were recorded in peripheral neural tissue and lesions were rare in other tissues. The condition appeared not to have been recorded previously in pheasants. A viral aetiology was suspected but Newcastle disease virus was not involved. 相似文献
1000.
The antifungal activity of natamycin toward molds isolated from commercially manufactured poultry feed 总被引:9,自引:0,他引:9
The antifungal activity of natamycin, a polyene antifungal compound, was evaluated on molds isolated from commercial poultry feed. The antifungal activity was measured by determination of the minimal inhibitory concentration (MIC) for natamycin on molds growing on semisolid microbiological medium (potato dextrose agar) containing pure natamycin at concentrations ranging from 0 to 200 mg/liter. Natamycin exhibited a high degree of antifungal activity against the 191 isolates of aspergilli used in this study, with average MIC values ranging from 5.08 to 40.1 mg/liter for Aspergillus fumigatus and Aspergillus parasiticus, respectively. Natamycin was also equally effective in inhibiting the growth of nonaflatoxigenic compared with aflatoxigenic isolates of Aspergillus flavus and A. parasiticus. Natamycin was also efficacious against molds other than aspergilli, with MIC values ranging from 2.15 to 5.80 mg/liter for Paecilomyces and Rhizopus spp., respectively. Natamycin exhibited apparent sporicidal activity against spores of toxigenic strains of Fusarium moniliforme and A. parasiticus but not Penicillium rubrum. This sporicidal activity was evident only when spores were exposed to an in vitro concentration of natamycin of 25 mg/liter or higher for a period of time of at least 12 hr. The growth inhibiting activity of natamycin was more pronounced compared with the sporicidal activity. 相似文献