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71.
T Takahashi Y Tamura T Sawada S Suzuki M Muramatsu T Fujisawa Y Benno T Mitsuoka 《Research in veterinary science》1989,47(2):275-276
The enzymatic activities of 39 strains of Erysipelothrix rhusiopathiae and 34 of E tonsillae were determined with the API ZYM system. The profiles of these two species were very similar, differing solely in N-acetyl-beta-glucosaminidase activity. Whereas 90 per cent of strains of E rhusiopathiae exhibited strong activity with N-acetyl-beta-glucosaminidase, positive reactions were observed for this enzyme in only 24 per cent of strains of E tonsillae. These results support previous DNA-DNA hybridisation studies and suggest that E tonsillae is a new species of the genus Erysipelothrix. 相似文献
72.
Large scale surveillance of FMD non-structural protein (NSP) antibody in pigs was conducted to monitor for FMD virus circulation in Taiwan using Ceditest and UBI NSP ELISA kits after recurrence of FMD in 2009. A total of 53,759 serum samples were collected from pigs in the auction markets in 2009. There were 43 farms with positive FMD NSP reactors to both NSP ELISA tests in the nationwide surveillance. After tracing back, clinical examination and the NSP ELISA testing using both Ceditest and UBI on 14 follow-up serum samples from all the herds with confirmed NSP reactors in 2009, there were 4 farms classified as positive on follow-up testing criteria. In this surveillance, we have demonstrated that the NSP ELISA tests of outbreak farms followed by clinical and serological investigation could be used to detect FMD circulation in the pig population in Taiwan even while the national compulsory vaccination program is ongoing. 相似文献
73.
Y Li H N Kadarmideen J C M Dekkers 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2008,125(5):320-329
The purpose of this study was to develop and investigate selection strategies that aim at maximizing long-term genetic response while conserving gene diversity and controlling inbreeding in populations of limited effective size, assuming complete knowledge of all genes affecting a quantitative trait. Three selection strategies were proposed to select on 100 quantitative trait loci (QTL) and compared with truncation selection on breeding value. Alternative selection strategies aimed at maximizing the average breeding value of parents with a penalty on (1) the number of unfavourable QTL genotypes among parents (OS-I), (2) the negative of the logarithm of the frequency of the favourable allele at each QTL among parents (OS-II), and (3) the average pedigree relationship among parents (OS-III). When all QTL and their effects were known, the strategies examined were able to obtain extra long-term responses, conserve QTL diversity and reduce inbreeding, compared with truncation selection. Strategy OS-II was the most effective in conserving QTL diversity and OS-III in reducing inbreeding. By changing the magnitude of the penalties applied, the impact on long-term response, inbreeding and diversity can be controlled. Extra long-term responses over truncation selection of OS-I and OS-II were even greater when effects of QTL were estimated rather than assumed known, indicating the applicability of results to practical strategies for marker-assisted selection. Extra responses are expected to be reduced for larger population sizes. 相似文献
74.
The present study was to investigate the feasibility and efficiency of the DNA vaccine to protect chickens against very virulent infectious bursal disease virus (vvIBDV) infection. A plasmid DNA carrying VP2‐4‐3 genes of vvIBDV SH95 and a plasmid DNA carrying chicken interleukin‐6 (ChIL‐6) genes were constructed and designated as pALTER‐MAX‐VP2‐4‐3 and pALTER‐MAX‐ChIL‐6 respectively. Several DNA vaccination experiments were performed: 1‐week‐old chickens were intramuscularly injected with only plasmid pcDNA3‐VP2, pALTER‐MAX‐VP2‐4‐3 or mixture with pALTER‐MAX‐ChIL‐6. The chickens at 4 weeks old were orally inoculated with vvIBDV SH95. The results showed that immunization with the mixture of pALTER‐MAX‐VP2‐4‐3 and pALTER‐MAX‐ChIL‐6 three times conferred protection for 90% of chickens. Enzyme‐linked immunosorbent assay (ELISA) antibody titres in chickens immunized together with pALTER‐MAX‐ChIL‐6 were higher than those immunized simply with plasmid pcDNA3‐VP2 or pALTER‐MAX‐VP2‐4‐3. IBDV was not detected in the bursa of the protected chickens at 8 days after challenge by RT‐PCR. The results indicate that protection against vvIBDV can be achieved by using the VP2‐4‐3 gene of vvIBDV as a DNA vaccine. Furthermore, the simultaneous injection of ChIL‐6 plasmid significantly increased the protection after challenge with the very virulent strain. 相似文献
75.
OBJECTIVES: To explore seizure management from the perspective of the owners of dogs with idiopathic epilepsy. METHODS: Questionnaires were mailed to owners of 29 dogs under management for suspected or diagnosed idiopathic epilepsy through the clinics of the Small Animal Hospital of the University of Glasgow Veterinary School, using either phenobarbitone or potassium bromide alone or in combination. RESULTS: The postal survey had an 86 per cent response rate. Analysis of the responses demonstrated that "the dog's quality of life", "adequate seizure frequency" and "acceptable side effects of antiepileptic drugs" were the three greatest concerns for owners; 52 per cent of owners strongly agreed that the seizure management for their dog was adequate, though the seizure frequency reported varied within this group; the majority of owners did not consider the administration of medication a nuisance. However, approximately 60 per cent of owners reported that caring for an epileptic dog had an effect on the organisation of their free time, though this was not dependent on perception of seizure control. Opinions as to the value of further diagnostic procedures, in particular intracranial imaging, were significantly affected by having pet health insurance. CLINICAL SIGNIFICANCE: From the owners' perspective, adequacy of seizure control is determined by the balance between "the dog's quality of life", "adequate seizure frequency" and "acceptable side effects of antiepileptic drugs". A frequency of less than one seizure every three months is associated with the perception by owners of adequate seizure control. 相似文献
76.
The protective effect of porcine antiserum prepared against culture filtrate (CF) of an attenuated strain of Erysipelothrix rhusiopathiae (serovar 2) in mice to challenge with 20 virulent strains of 18 serovars and one type N was investigated. Passively immunized mice survived after challenge with serovars 1a, 1b, 2, 5, 6, 8 (strain Goda), 11, 12, 15, 16, 21 or type N, but 10-30% mortality occurred in immunized mice challenged with each strain of serovars 4, 7, 8 (strain 911), 9, 18 or 19 and 70% mortality to serovar 10 (strain 2179). All immunized mice died after challenge with serovar 20 (strain 2553). Non-treated control mice died after challenge with all serovars and the type tested. 相似文献
77.
Virulence factors in Escherichia coli isolated from piglets with neonatal and post-weaning diarrhea in Japan 总被引:9,自引:0,他引:9
A total of 567 strains of Escherichia coli were isolated from piglets with neonatal diarrhea (ND) or post-weaning diarrhea (PWD) in Japan. They were investigated for enterotoxigenicity and possession of adhesins and O antigens. There were clear differences between the strains of ND origin and those of PWD origin in the occurrence of enterotoxigenic E. coli (ETEC) strains, type of enterotoxin and frequency of adhesins: ETEC was found in 77 (25.7%) of 300 strains of ND origin and in 137 (51.3%) of 267 strains of PWD origin. ETEC strains producing heat-labile enterotoxin (LT) or heat-stable enterotoxin (STa), alone or in combination were evenly distributed among the strains of PWD origin. In contrast most of the ETEC strains of ND origin produced LT alone. Adhesins appeared in 42 (54.5%) of 77 ETEC strains of ND origin and in 36 (26.3%) of 137 ETEC strains of PWD origin. Adhesins were less common in ETEC strains of PWD origin than in those of ND origin. Some K99-positive ETEC strains of PWD origin produced both LT and STa. There was a similarity in the distribution of O antigens, particularly O149 and O157, between the strains of ND origin and those of PWD origin. 相似文献
78.
Adherence of four virulent and four avirulent strains of Erysipelothrix rhusiopathiae, serovar 1a, to porcine kidney cell lines, PK-15 and ESK cells, was examined in an in vitro system. The virulent strains adhered well to the cells (range of means, 9.95 +/- 0.87-36.01 +/- 1.10 per cell). In contrast, the avirulent strains showed negligible adherence to the cells (range of means, 0.11 +/- 0.04-1.41 +/- 0.13 per cell). Pretreatment of bacteria with heat, trypsin, or antiserum resulted in a marked decrease in adherence. Scanning electron microscopic examination revealed that the bacteria attached directly to the microvilli of cells. 相似文献
79.
80.
Niora J. Fabian Michael Y. Esmail Lauren Richey Sureshkumar Muthupalani Jennifer L. Haupt Joanna Joy Sebastian E. Carrasco 《Journal of veterinary diagnostic investigation》2021,33(3):582
Cutaneous leiomyosarcomas are malignant mesenchymal tumors of smooth muscle origin and are reported occasionally in avian species. A 14-y-old male laboratory White Carneau pigeon (Columba livia) was presented for surgical excision of a cervical soft tissue mass. Ultrasonography with color flow Doppler imaging revealed multiple cavitations of mixed echogenicity within the mass and vascularization. Histologically, the dermis and subcutis were expanded by a densely cellular multinodular mass comprised of fusiform cells forming haphazardly arranged broad streams and short interwoven bundles, often surrounding blood vessels and variably sized cavitations. Neoplastic cells were strongly immunopositive for desmin and α–smooth muscle actin, and negative for pancytokeratin, S100, and von Willebrand factor. Based on histopathology and IHC findings, the cutaneous mass was diagnosed as leiomyosarcoma (LMS). The pigeon died 312 d post-operatively. Postmortem examination revealed masses infiltrating the left and right pulmonary airways and one hepatic nodule, but no regrowth at the surgical site. Histologic and IHC evaluation of the pulmonary and hepatic masses were consistent with LMS, representing metastatic foci from the primary cutaneous LMS. Our case highlights the malignant behavior and histomorphologic features of cutaneous LMS in an avian species. 相似文献