Neuraminidase production by Erysipelothrix rhusiopathiae

In order to characterise neuraminidase activity by Erysipelothrix, 85 isolates of Erysipelothrix spp. from a variety of sources including human clinical, marine and terrestrial animals, and the environment were investigated for neuraminidase production. Neuraminidase activity was detected by a peanut lectin haemagglutination method. The effects of media, incubation conditions and pH on the production and activity of neuraminidase were also investigated. Enzyme activity was detected only in the supernatants of the isolates of Erysipelothrix rhusiopathiae which had been incubated in cooked meat broth and Todd Hewitt broth supplemented with horse serum after 16 and 36 h incubation at 37 degrees C. The maximum titres were reached at 40 h in cooked meat broth and 56 h in Todd Hewitt broth supplemented with horse serum. All 58 isolates and the type strain (ATCC 19414) of E. rhusiopathiae produced detectable neuraminidase activity with titres between 10 and 320. The optimal pH for the enzyme activity varied among the isolates with a pH between 6.0 and 7.0 covering the highest enzyme activity of the most. There was no statistically significant difference in the level of neuraminidase activity between isolates from different sources (p > 0.05). Neuraminidase activity was not detected in the non-pathogenic Erysipelothrix spp. such as E. tonsillarum. Neuraminidase was detected only in E. rhusiopathiae suggesting its possible role as a virulence factor. Enzyme production and activity were medium and pH dependent. The peanut lectin haemagglutination assay is a simple, rapid and sensitive method and is particularly useful for the analysis of multiple samples.     

中国兽医生物安全实验室建设与管理

1 生物安全(biosafety) 　　1.1 生物安全的定义 　　生物安全就是“生命安全“.对于兽医工作者来说,就是防止动物病原体进入动物体内或存留在动物所在的地方,防止动物病原体的传播和扩散.它涉及多项措施,旨在防止动物病原体的感染、传播与流行,防止对人类造成危害.……     

口服补液盐的临床应用与动物实验研究

作者于1983年开始将以葡萄糖—钠泵学说为理论的口服补液盐(ORS)技术引入我国畜牧兽医领域,经过几年的临床研究;先后在防治犊牛、猪、雏鸡和犬的腹泻脱水等获得86～98.7％的成功率。健康绵羊ORS液吸收实验和与静脉输液、口服蒸溜水吸收比较实验证明,ORS液的各种成分在服后2小时内,不仅能被胃肠粘膜吸收,极显著改善红细胞压积(P<0.01),而且初步观察到促水分吸收的葡萄糖—钠泵现象。     

河北进境种用动物衣原体血清学检测

衣原体病是一种重要的人畜共患病,给养殖业带来巨大的经济损失,同时严重威胁从业人员的身体健康。本研究对河北辖区引进的2批种鸡、2批种鸭及2批种猪进行抽样,使用间接血凝试验（IHA）检测引进种用动物的衣原体抗体。结果表明：衣原体IHA抗体阳性率为15.7%。在种鸡、种鸭和种猪中均检测到衣原体IHA抗体,阳性率分别为18.1%、4.2%和20%。这说明在引进种用动物中存在着较高的衣原体抗体阳性率,需要加强对该病的检测。     

世界各国动物源残留监控体系概况

本文着重介绍了欧盟、美国和澳大利亚的动物源残留监控情况并对2009年的监控报告进行了分析总结。     

日本食品企业实施HACCP体系认证的现状及其问题

<正>HACCP(Hazard Analysis and Critical Control Point,危害分析和关键点控制)的概念于20世纪60年代,由美国Pillsbury公司的Howard Bauman博士及其同事在一项太空食品研究计划中提出。HACCP体系已成为国际公认的能够确保食品安全的有效控制管理体系,是近年来发达国家在食品和饲料质量管理中普遍采用的管理体系。     

利用16S rRNA全长序列鉴定植物乳杆菌

从标明含有嗜酸乳杆菌的活菌胶囊中分离到一株乳杆菌Lal菌株，利用16S rRNA全序列分析法和传统分类法对Lal菌株进行分类鉴定表明：Lal菌株属于植物乳杆菌种新株系，该菌株现在已经被中国科学院北京微生物所菌种保藏中心收录保存，编号为ASl．2986。     

泰山粗毛型长毛兔高产品系选育研究

以德系、法系安哥拉、沪２０７１ 系和ＧＳＡＢ兔为育种素材,通过合成杂交方式建立选育基础群,实施半开放式核心群世代选育,经过５ 个世代育成粗毛型兔新品系。新品系平均年产毛量１７０４ｇ,兔毛品质优良,粗毛率２０．１１％ ,料毛比４０．３３∶１,成年体重５．５ｋｇ,体长５５ｃｍ ,胸围４０ｃｍ ,平均窝产仔７．３６只,育成成活率９２％ 。适应性和抗病力较强,体质健壮,外貌整齐,遗传性稳定     

浅谈二噁英的检验技术

1　检测二口恶英的技术难度食品和饲料中二口恶英及其类似物的检验属于超痕量级检验,通常以ｎｇ/ｋｇ和ｐｇ/ｋｇ表示。它比其他污染物含量低千倍到亿倍以上,检测难度很大,其多组分即同系物、异构体的化学前处理技术几乎包罗近代最先进的手段,涉及分离、富集、提取、净化、清洗和浓缩装置,还包含自动凝胶色谱(ＡｕｔｏｍａｔｅｄＧｅｌＰｅｒｍｅａｔｉｏｎＣｈｒｏｍａｔｏｇｒａｐｈｙ)、反相ＨＰＬＣ、玻璃色谱柱等。检测过程需要尖端大型分析仪器的支持,定量分析依靠ＨＲＧＣ/ＨＲＭＳ,对仪器的灵敏度、选择性和特异性要求极高,是现今分…