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Multiple skin nodules, with histological features of adnexal tumours consistent with trichoepithelioma, were observed on the head and trunk of Syrian hamsters. Skin biopsies from 20 hamsters from five different colonies were affected, and two of the affected hamsters also had lymphoma. Two owners reported that 16 of 70 hamsters and 50 of 100 hamsters in their colonies had similar skin lesions. These tumours have previously been associated in laboratory colonies with hamster polyomavirus (HaPV) infection. Examination of skin tissues by electron microscopy failed to reveal intranuclear virus particles. Using recombinant major capsid protein VP1 of HaPV, VP1-specific antibodies were detected in sera from 12 of 12 affected hamsters and in four of four unaffected in-contact hamsters, by ELISA. The ELISA data were verified by immunoblot analysis. Eleven of 13 serum samples contained antibodies which reacted with at least one recombinant structural HaPV protein (VP2), including samples from three in-contact unaffected hamsters. Nine of the 11 anti-VP2-positive samples also reacted with recombinant VP3 of HaPV, and six reacted with VP1. Amplification by PCR and sequencing detected VP1 -encoding sequences showing a high degree of homology with HaPV. The findings suggest a possible infection by HaPV or a HaPV-like virus and it is likely that such an infection was enzootic within the affected colonies.  相似文献   
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OBJECTIVE: To determine which antimicrobials that are used to treat neonatal foals with septicemia attributable to Escherichia coli will minimize endotoxin release from bacteria and subsequent activity of inflammatory mediators while maintaining bactericidal efficacy. SAMPLE POPULATION: Blood samples from 10 healthy foals. PROCEDURE: Escherichia coli isolates A and B were isolated from 2 septicemic foals, and minimal inhibitory concentrations (MIC) were determined for 9 antimicrobials. Five of these antimicrobials were tested in vitro at 2 and 20 times their respective MIC. Whole blood or mononuclear cells grown in tissue-culture media were incubated with 105 colony-forming units of E. coli and each antimicrobial or saline (0.9% NaCl) solution. After 6 hours, number of viable bacteria remaining was determined, and supernatant was tested for endotoxin and tumor necrosis activity. RESULTS: Testing in whole blood was compromised by bactericidal effects of the blood itself. In mononuclear cell suspensions, each antimicrobial significantly reduced the number of viable bacteria to low or undetectable amounts. Antimicrobials did not differ significantly in efficacy of bacterial killing. Amikacin used alone or in combination with ampicillin resulted in significantly less endotoxin activity than did ampicillin, imipenem, or ceftiofur alone. There was a correlation between TNF-alpha and endotoxin activity. CONCLUSIONS AND CLINICAL RELEVANCE: Aminoglycosides appear less likely to induce endotoxemia and TNF-alpha synthesis during bactericidal treatment of E. coli septicemia, compared with beta-lactam antimicrobials. Use of ampicillin, imipenem, or ceftiofur in the treatment of septicemic neonatal foals should be accompanied by appropriate treatment for endotoxemia.  相似文献   
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A seven-year-old neutered male cocker spaniel was presented with an 11-month history of generalised bacterial dermatitis. There were skin lesions over the entire body, which were round, slightly raised and encrusted. Skin biopsies were collected and the histological findings were consistent with pemphigus foliaceus. Immunohistochemical staining by the indirect immunoperoxidase method was positive, with desmosomal deposition of immunoglobulin (Ig) G. Haematological analysis revealed a regenerative anaemia and profound thrombocytopenia, while a Coombs' test was positive for polyvalent canine Coombs' reagent and anti-dog IgG. An antinuclear antibody test was positive, with a titre of 10,240. An ophthalmic examination demonstrated low tear production (keratoconjunctivitis sicca). Seven months after initial referral, the dog was re-presented with severe generalised peripheral lymphadenopathy. Radiographic evaluation of the thorax and abdomen revealed enlarged cranial mediastinal and sublumbar lymph nodes. Tru-Cut biopsy from an enlarged lymph node confirmed the diagnosis of lymphoma, which was phenotyped as a B-cell tumour. The diagnosis in this case was systemic lupus erythematosus, with the unusual feature of pemphigus foliaceus, and subsequent development of B-cell lymphoma. The case adds further to knowledge of the protean clinical presentations of canine autoimmune diseases and provides additional evidence for the potential association between autoimmunity and immune-system neoplasia in this species.  相似文献   
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Pasteurella multocida is responsible for major animal diseases of economic significance in both developed and developing countries whereas human infections related to this bacterium are infrequent. Significantly, development of a carrier status or latent infections plays a critical role in the epidemiology of these diseases. Aiming at increased knowledge of these infections, we examine potential diagnostic and selected typing systems for investigating diseases caused by P. multocida. Detection of P. multocida from clinical specimen by; (i) isolation and identification, (ii) polymerase chain reaction (PCR), iii) specific hybridisation probes, (iv) serological tests and (v) other alternative methods is critically evaluated. These detection systems provide a wide spectrum of options for rapid diagnosis and for detecting and understanding of latent infections in herd/flock health control programmes, though PCR methods for detecting P. multocida in clinical specimen appear increasingly preferred. For establishing the clonality of outbreak strains, we select to discuss macromolecular profiling, serotyping, biotyping, restriction enzyme analysis, ribotyping and multiplex PCR typing. Although P. multocida infections can be rapidly diagnosed with molecular and serological tests, isolation and accurate species identification are central to epidemiological tracing of outbreak strains. Our review brings together comprehensive and essential information that may be adapted for confirming diagnosis and determining the molecular epidemiology of diseases associated with P. multocida.  相似文献   
17.
广西梧州市农場印度摩拉水牛,雄性,因打架,胸部左側严重负伤曆鴨T未及时报告,待发現时伤口已肿大化脓,內已生蛆丝谥本?公分,基部6公分,恶臭。处理方法:先用高錳酸鉀溶液冲洗伤口,除去蛆虫,后用桃叶若干,石灰少許,共同捣碎,填塞于伤口內,到填滿为止,外塗凡士林(仅防蝇叮虫咬),只用药一次,数日后伤口痊癒。  相似文献   
18.
A seven-year-old Labrador was presented with weight loss and mild generalised lymphadenopathy. Histopathology of an excised lymph node by the referring veterinarian demonstrated granulomatous lymphadenitis. At the time of referral, fine-needle aspirates of the lymph nodes confirmed the presence of ongoing granulomatous inflammation. Further investigations revealed marked hypercalcaemia, a low parathyroid hormone concentration, a parathyroid hormone related protein concentration within the reference range, and an elevated serum concentration of 1,25 dihydroxyvitamin D. An underlying cause of the granulomatous lymphadenitis could not be identified. The clinical signs, hypercalcaemia and elevated serum concentrations of 1,25 dihydroxyvitamin D resolved following prednisolone treatment. In contrast to dogs, hypercalcaemia occurred secondarily to granulomatous disease and elevated 1,25 dihydroxyvitamin D concentrations is a well-recognised condition in human beings. To the authors' knowledge, this is the first case report to describe elevated serum calcium and 1,25 dihydroxyvitamin D concentrations in a dog with histologically confirmed granulomatous disease.  相似文献   
19.
Rhabdoviruses infect a variety of hosts, including non-avian reptiles. Consensus PCR techniques were used to obtain partial RNA-dependent RNA polymerase gene sequence from five rhabdoviruses of South American lizards; Marco, Chaco, Timbo, Sena Madureira, and a rhabdovirus from a caiman lizard (Dracaena guianensis). The caiman lizard rhabdovirus formed inclusions in erythrocytes, which may be a route for infecting hematophagous insects. This is the first information on behavior of a rhabdovirus in squamates. We also obtained sequence from two rhabdoviruses of Australian lizards, confirming previous Charleville virus sequence and finding that, unlike a previous sequence report but in agreement with serologic reports, Almpiwar virus is clearly distinct from Charleville virus. Bayesian and maximum likelihood phylogenetic analysis revealed that most known rhabdoviruses of squamates cluster in the Almpiwar subgroup. The exception is Marco virus, which is found in the Hart Park group.  相似文献   
20.
The effects of three preslaughter diets on heifer beef quality were investigated. Heifers (n = 45) were divided into three groups and fed for ad libitum consumption either maize silage, grass silage, or a 50:50 mixture of maize silage and grass silage. Meat quality was determined by measuring color, lipid oxidation, alpha-tocopherol levels, and fatty acid composition. Beef from the maize silage group had poorest color stability (P < 0.05), whereas beef from the grass silage diet had best (P < 0.05) color stability. The visual panel least preferred the maize silage group after 2 or more days of display, and lipid oxidation was significantly (P < 0.001) higher in this group compared to the 50:50 maize:grass silage and grass silage groups. There was a significant (P < 0.001) difference in the alpha-tocopherol levels detected in the meat from the three dietary groups. Alpha-tocopherol levels increased in the order: maize silage < 50:50 maize:grass silage < grass silage, at levels of 2.08, 2.95, and 3.84 microg/g meat, respectively. Fatty acid analysis indicated 18:3 was significantly (P < 0.001) lower in the maize silage-fed group than in the maize:grass silage and grass silage groups. However, 18:3 was significantly (P < 0.001) higher in the grass silage group than in the other two groups. There were no significant differences in all other fatty acids among the three dietary groups. It was concluded that beef from grass silage-fed animals had better overall quality in terms of color, lipid oxidation, and alpha-tocopherol levels than beef from maize silage fed animals.  相似文献   
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