山羊瘤胃中单宁降解菌的分离、筛选和鉴定

本试验旨在从山羊瘤胃中分离、筛选和鉴定单宁降解菌。从隆林山羊瘤胃采集内容物,采用单宁浓度耐受培养基进行初筛,再采用单宁酶活力鉴定培养基分离、筛选单宁降解菌,筛选出的细菌通过16S r DNA基因序列测定初步鉴定,将菌株在单宁浓度为0.5%、1%、1.5%的单宁酶诱导培养基中培养,测定酶活力。结果表明:共分离、筛选到4株降解单宁的细菌,根据16S r DNA基因序列分析结果,分别为产碱普罗威登斯菌(Providencia alcalifaciens)、克斯特菌(Kerstersia)、普罗威登斯菌(Providencia vermicola)和铜绿假单胞菌(Pseudomonas aeruginosa)。经单宁酶诱导培养基培养后,Kerstersia的胞内单宁酶活力高于其他3株菌,而其他3株菌的酶活力较为接近;Kerstersia、Providencia vermicola和Pseudomonas aeruginosa经1%单宁浓度诱导的单宁酶活力均高于经0.5%和1.5%单宁浓度诱导(P0.05)。本试验成功从山羊瘤胃中筛选、分离、鉴定出4株单宁降解菌,且它们均表现出较高的单宁酶活力。     

中国草地自然灾害及其防治对策

介绍了中国草地的五大自然灾害,提出了综合防治的五项对策。     

An equine herpesvirus 1 (EHV-1) vectored H1 vaccine protects against challenge with swine-origin influenza virus H1N1

In 2009, a novel swine-origin H1N1 influenza A virus (S-OIV), antigenically and genetically divergent from seasonal H1N1, caused a flu pandemic in humans. Development of an effective vaccine to limit transmission of S-OIV in animal reservoir hosts and from reservoir hosts to humans and animals is necessary. In the present study, we constructed and evaluated a vectored vaccine expressing the H1 hemagglutinin of a recent S-OIV isolate using equine herpesvirus 1 (EHV-1) as the delivery vehicle. Expression of the recombinant protein was demonstrated by immunofluorescence and western blotting and the in vitro growth properties of the modified live vector were found to be comparable to those of the parental virus. The EHV-1-H1 vaccine induced an influenza virus-specific antibody response when inoculated into mice by both the intranasal and subcutaneous routes. Upon challenge infection, protection of vaccinated mice could be demonstrated by reduction of clinical signs and faster virus clearance. Our study shows that an EHV-1-based influenza H1N1 vaccine may be a promising alternative for protection against S-OIV infection.     

A/H1N1研究进展

2009年3以来,包括墨西哥、美国和加拿大在内的许多国家发生了甲型H1N1流感[Swine-origin Influenza A (A/H1N1)]疫情,WHO已于2009年6月20日将此次流感流行的预警级别提升至6级.现已基本明确,引起此次流感疫情的A/H1N1流感病毒是猪流感病毒(Swine Influenza Virus, SIV)的一种新型变异株.此次流感疫情的发生,再次使猪流感成为社会各界关注的焦点之一.本文就甲型H1N1流感的临床表现、病毒特征、相互关系及其对动物卫生监督工作的影响等作一综述.     

鸽禽I型副粘病毒油佐剂灭活苗对肉种鸽免疫效果观察

用鸽Ａ／ＰＭＶ－１ＳＸ株（简称ＳＸ株）制成的油佐剂灭活苗与ＮＤＶ油佐剂灭活苗分别免疫肉种鸽,免疫后２０天抗体水平达到峰值,抗体水平在３ｌｏｇ２以上维持３０天以上。免疫后４０天用鸽ＳＸ株和新城疫强毒对两种疫苗免疫鸽分别进行攻击,两种疫苗免疫组对ＮＤＶ强毒攻击的保护率均为１００％,鸽Ａ／ＰＭＶ－１油佐剂灭活苗免疫组对鸽ＳＸ株攻击的保护率为１００％,而ＮＤＶ油佐剂灭活苗免疫组对鸽ＳＸ株攻击的保护率仅为６６７％。鸽Ａ／ＰＭＶ－１油佐剂灭活苗田间试验抽检４８份肉种鸽血清,抗体平均值为４３０±１１６ｌｏｇ２。     

欧亚类禽H1N1与古典H1N1亚型猪流感病毒NA基因遗传进化分析

本研究对2011年分离自吉林省猪群的3株流感病毒进行了遗传进化分析。结果表明欧亚类禽H1N1猪流感病毒和古典H1N1猪流感病毒在吉林省猪群中共同流行,因此加强猪流感流行病学调查具有重要意义。     

甲型H1N1流感病毒NS1蛋白核仁定位的研究

为研究2009年甲型H1N1流感病毒的NS1蛋白的核仁定位情况,采用RT-PCR对其NS1基因进行了扩增,将其克隆至PEGX-KG载体,构建重组质粒KG-NS1,转化大肠杆菌BL21,IPTG诱导表达重组蛋白.然后采用GST柱亲和层析方法纯化NS1重组蛋白,免疫家兔来制备多抗,Western blot检测抗体.通过间接免疫荧光对表达不同长度NS1 (NS1-219、NS1-230、NS1-237)的3种重组流感病毒进行了核仁定位的研究,3种重组毒的NS1蛋白存在于细胞核和细胞质,但都不能定位于核仁,说明NS1蛋白的截短与否并不影响其核仁定位,其生物学意义有待于进一步研究.     

Reassortant H1N1 influenza virus vaccines protect pigs against pandemic H1N1 influenza virus and H1N2 swine influenza virus challenge

Influenza A (H1N1) virus has caused human influenza outbreaks in a worldwide pandemic since April 2009. Pigs have been found to be susceptible to this influenza virus under experimental and natural conditions, raising concern about their potential role in the pandemic spread of the virus. In this study, we generated a high-growth reassortant virus (SC/PR8) that contains the hemagglutinin (HA) and neuraminidase (NA) genes from a novel H1N1 isolate, A/Sichuan/1/2009 (SC/09), and six internal genes from A/Puerto Rico/8/34 (PR8) virus, by genetic reassortment. The immunogenicity and protective efficacy of this reassortant virus were evaluated at different doses in a challenge model using a homologous SC/09 or heterologous A/Swine/Guangdong/1/06(H1N2) virus (GD/06). Two doses of SC/PR8 virus vaccine elicited high-titer serum hemagglutination inhibiting (HI) antibodies specific for the 2009 H1N1 virus and conferred complete protection against challenge with either SC/09 or GD/06 virus, with reduced lung lesions and viral shedding in vaccine-inoculated animals compared with non-vaccinated control animals. These results indicated for the first time that a high-growth SC/PR8 reassortant H1N1 virus exhibits properties that are desirable to be a promising vaccine candidate for use in swine in the event of a pandemic H1N1 influenza.