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61.
猪、禽安全生产中主要病原菌耐药性检测及控制技术研究进展 总被引:1,自引:0,他引:1
国内外研究及本课题组的调查表明,猪、禽养殖中主要病原菌的耐药性日趋严重,细菌产生耐药性的机理复杂多样.而药性的检测技术在常规药敏试验的基础上,国内外学者及本课题组已将质粒指纹图谱,PCR,SSCP,核酯探针等分子生物学技术用于耐药性检测.本文还综述和提出了加强兽药管理、制定用药规范、研究质粒消除技术、开发出针对性疫苗、益生素、噬菌体制剂等一系列耐药性的控制技术. 相似文献
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Ghosh TK Haldar S Bedford MR Muthusami N Samanta I 《Journal of animal physiology and animal nutrition》2012,96(2):275-284
The study compared the effects of an antibiotic growth promoter (AGP), yeast (Saccharomyces cerevisiae) and yeast cell wall (YCW) on performance, microbiology and histo-morphology of the small intestine and humoral immune responses in Ross 308 broilers. The treatments (eight replicates/treatment, n = 12/replicate) were negative control (NC, without AGP), positive control (PC, supplemented with bacitracin methylene disalicylate, 400 mg/kg), Y and YCW (supplemented with yeast and YCW, respectively, 1000 mg/kg). Live weight at 42 days improved (p = 0.086) in the PC, Y and YCW groups. Feed conversion ratio was better (p = 0.039) in the YCW group compared with the other groups. Antibiotic growth promoter in the PC group shortened the villi in duodenum (p = 0.044). Mucosal Escherichia coli number was higher in the PC group (p < 0.001), whereas in the digesta E. coli number was lower (p = 0.001) in the PC, Y and YCW groups in relation to the NC. Mucosal Salmonella populations increased (p = 0.0001) in the PC group, whereas in the digesta, all treatments reduced the Salmonella (p = 0.0001). Following oral challenge with Salmonella pullorum, YCW increased E. coli numbers on the mucosa (p < 0.001) whereas in the digesta the Y group had lower (p < 0.0001) number of E. coli. In the digesta, Salmonella count was lower in the YCW group compared with the other treatments (p < 0.01). Yeast cell wall -treated birds exhibited better (p < 0.05) humoral immune response against Newcastle disease which was far more persistent over time than in any other treatments. It was concluded that the yeast and the yeast cell wall may have effects identical to BMD on performance of broilers and thus may constitute an effective replacement strategy in the dietary regimens for broiler chickens. 相似文献
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Eltayb A Barakat S Marrone G Shaddad S Stålsby Lundborg C 《Zoonoses and public health》2012,59(5):330-338
Antibiotic resistance is a major emerging global public health threat. Farmers in the Khartoum state are believed to misuse antibiotics in animal farming leading to daily exposure to resistant bacteria and antibiotic residues. Hence, farmers are at potential risk exposure to bacteria, zoonotic infection and toxicity. We hypothesized that farmers' misuse of antibiotics could be due to their ignorance of the importance of optimal use of antibiotics, the potential health hazards and the economical waste associated with antibiotic misuse practices. In the present study, we investigated knowledge and practices among farmers regarding antibiotic use and resistance. For this purpose, a cross-sectional study was conducted in Khartoum state where data were collected from 81 farmers using structured interviews. Data were analysed both quantitatively and qualitatively. Fifty-two per cent of farmers were uneducated or had studied for < 6 years. The majority reported antibiotic use for treatment and prevention while only 5% stated use for growth promotion. Antibiotic group treatment for both sick and healthy animals was commonly practiced among most farmers. The most commonly used group of antibiotics was the quinolones, which was reported by one-third. Only 30% of the farmers had heard of antibiotic resistance and provided their definition. Almost half were not aware of the commonly transferred zoonotic infections between humans and animals. The farmers consume 1-2 meals/day from their own farm products. A significant association between low education, poor knowledge of farmers on antibiotic use, antibiotic resistance and zoonotic infections was found. This association may play a vital role in the present practiced misuse of antibiotics. Our findings on farmers' practices could be used as baseline information in defining the gaps related to antibiotic use and resistance in animal farming in Sudan. It can thus serve as a foundation for future interventions. 相似文献
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研究卡那霉素、潮霉素、头孢霉素和羧苄青霉素对剑麻愈伤组织生长、不定芽分化及生根的影响,并确定抑制农杆菌生长的头孢霉素、羧苄青霉素的质量浓度。结果表明:潮霉素明显抑制剑麻愈伤组织生长和不定芽分化,卡那霉素次之,头孢霉素和羧苄青霉素相对较小;4种抗生素均能抑制剑麻生根,其抑制效果依次为头孢霉素>卡那霉素>羧苄青霉素>潮霉素。头孢霉素和羧苄青霉素的浓度大于200 mg/L时,农杆菌生长完全被抑制。在筛选剑麻转化体时,卡那霉素和潮霉素的使用浓度分别以100、50 mg/L为宜,羧苄青霉素和头孢霉素的使用浓度均为200 mg/L。 相似文献
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Maria Foti Cristina Giacopello Vittorio Fisichella Giuseppe Latella 《Journal of Exotic Pet Medicine》2013,22(3):270-274
Pseudomonas aeruginosa represents an opportunistic pathogen for animals and humans that is often associated with high disease morbidity and, at times, mortality. Captive reptiles have been shown to be reservoirs of P. aeruginosa strains that can be sources of exposure to humans that come in contact with these animals. In this study, the prevalence of P. aeruginosa among subclinical captive reptile species and the antimicrobial sensitivity of bacterial isolates were investigated. Sixty-five oral swabs were collected from captive reptiles belonging to 15 different species in which no overt signs of disease were evident. From this group of animals, 46 (70.8%) isolates were identified as P. aeruginosa. All of the P. aeruginosa strains were shown to have a wide range of antibiotic resistance. At present, there is a paucity of data regarding the prevalence of P. aeruginosa in various reptile species; therefore, continued scientific investigations are indicated to determine the significance of P. aeruginosa infection as it relates to captive reptile species. 相似文献