Serological Survey of Toxoplasma gondii Infection in the Domestic Goose (Anser domestica) in Southern China

In the present study, the antibodies to Toxoplasma gondii in 191 farm‐bred and 83 house‐bred geese (Anser domestica) were assessed for the prevalence of T. gondii infection in southern China with the modified agglutination test. Antibodies to T. gondii (MAT ≥ 1 : 5) were found in 27 (14.14%) of farm‐bred geese and 14 (16.87%) of house‐bred geese. Geese infected with T. gondii may be a source of T. gondii infection for humans and cats.     

Vaccination of chickens with a chimeric DNA vaccine encoding Eimeria tenella TA4 and chicken IL-2 induces protective immunity against coccidiosis

A fusion DNA vaccine co-expressed Eimeria tenella TA4 and chicken IL-2 (chIL-2) was constructed and its efficacy against E. tenella challenge was observed. TA4 gene of E. tenella and chIL-2 gene were cloned into expression vector pcDNA3.1 and pcDNA4.0c in different forms, producing vaccines pcDNA3.1-TA4-IL-2, pcDNA3.1-TA4 and pcDNA4.0c-IL-2. The expression of aim genes in vivo was detected by RT-PCR and western blot. Animal experiment was carried out to evaluate the immune efficacy of the vaccines. Results indicated these DNA vaccines were successfully constructed and the antigen genes could be expressed effectively in vivo. The animal experimental results showed that DNA vaccines could obviously alleviate cecal lesions, body weight loss and increase oocyst decrease ratio. The ACI of pcDNA3.0-TA4-IL-2 group was 192, higher than that of pcDNA3.1-TA4 group. The results suggested that TA4 was an effective candidate antigen for vaccine and co-expression of cytokine with antigen was an alternative method to enhance DNA vaccine immunity.     

Cytotoxicity of gamma-ray in rat immature hippocampal neurons

This in vitro study evaluated the detrimental effect of acute gamma (γ)-irradiation on rat immature hippocampal neurons. Rat immature hippocampal neurons (0.5 day in vitro) were irradiated with 0~4 Gy γ-rays. Cytotoxicity was analyzed using a lactate dehydrogenase release assay at 24 h after γ-irradiation. Radiation-induced cytotoxicity in immature hippocampal neurons increased in a dose-dependent manner. Pre-treatments of pro-apoptotic caspase inhibitors and anti-oxidative substances significantly blocked γ-irradiation-induced cytotoxicity in immature hippocampal neurons. The results suggest that the caspase-dependent cytotoxicity of γ-rays in immature hippocampal cultured neurons may be caused by oxidative stress.     

犊牛大肠杆菌病的诊治

2010年5月,黑龙江省双城市某乡先后有3位畜主来我院对其所养的5头犊牛发病情况进行就诊。通过询问得知,这几头犊牛基本都是刚出生半个月左右。病犊发热,精神沉郁或昏迷。间有腹泻,有2头死前发生腹泻,并有明显的脖颈扭转现象。另外2头犊牛发病初期排出黄色粥样粪便,后期排灰白色水样粪     

广西玉林市规模化禽场禽流感病毒检测

为了解广西玉林市2020年规模禽场禽流感病毒感染状况,采用荧光RT-PCR方法,对广西玉林市7个县(市、区)42个规模化禽场采集的1260份禽喉/泄殖腔棉拭子样品进行了通用型禽流感病毒核酸检测(荧光PCR),并对检测为阳性的样本进行H5、H7亚型(双重荧光PCR)和H9亚型(荧光PCR)分型鉴定.结果显示:在42个规模...     

液相色谱-串联质谱法测定猪尿液中地西泮及其7种代谢物残留

为建立快速测定猪尿中地西泮及其7种代谢物残留的超高效液相色谱-串联质谱(UPLC-MS/MS)确证方法,本研究优化了样品净化的阳离子交换固相萃取柱(PCX柱)及其淋洗洗脱条件.猪尿液酸化后直接经PCX柱净化,依次用水、60％ 甲醇水溶液淋洗,最后用5％ 氨化甲醇洗脱;选用BEH C18色谱柱分离,UPLC-MS/MS进...     

饲料添加剂类抗生素替代品在生猪养殖中的研究进展

随着现代社会的发展,集约化养殖成为主流趋势,抗生素的缺失往往会给养殖者带来巨大损失.但是,长期以来,抗生素滥用导致的细菌耐药性和药物残留问题日益严峻.随着我国2020年饲料添加剂类的抗生素的禁用,寻找高速、有效的抗生素替代品成为养殖业急需解决的重要问题.近年来,涌现出的各种饲料添加剂,如酸化剂、微生态制剂、酶制剂、植物...     

甘肃省天水市生猪屠宰企业非洲猪瘟检测能力提升措施

着力加强和提升生猪屠宰企业非洲猪瘟检测实验室建设是有效防范非洲猪瘟传播的重要手段。为进一步提升屠宰企业非洲猪瘟自检能力,对甘肃省天水市生猪屠宰企业非洲猪瘟自检体系建设和运行情况进行了实地调研,并针对不足之处提出系列提升指导措施。调研发现:2019年以来,通过优化实验室配置、增加检测人员数量、加强检测人员培训和强化生物安全防护措施等,天水市屠宰企业非洲猪瘟检测能力明显提升。本文为我国其他地区生猪屠宰企业提升非洲猪瘟自检能力提供了参考。     

云南省部分养殖场鸡传染性贫血病毒核酸检测及VP2基因序列分析

为了解云南省鸡传染性贫血病毒（chicken anemia virus,CAV）的流行及其VP2基因变异情况,2017—2020年,在昆明市、楚雄州、大理州、红河州、玉溪市等家禽养殖密集区的89个鸡场,采集422份疑似病鸡肝脏样品,通过PCR方法检测CAV核酸。结果显示,检出阳性245份,平均阳性率为58.06%;不同年份的CAV核酸阳性率为53.61%~60.91%,不同区域核酸阳性率为51.68%~63.52%。对3份CAV阳性样品进行VP2基因序列分析,发现核苷酸序列同源性为99.6%~99.8%,与参考毒株1852TW和N7的核苷酸同源性为99.6%~99.8%,均属于GroupA分支。结果表明：云南省普遍存在CAV感染,且感染较严重;VP2基因仍可作为PCR病毒核酸检测的首选目标基因。通过加强鸡群CAV监测,淘汰阳性鸡群和结合疫苗免疫,可减少该病造成的损失。     

一起野禽H5N8亚型禽流感疫情的处置与思考

2021年1月,江苏省连云港市云台山景区云台街道西隅水库发生一起疑似野禽H5N8亚型禽流感疫情,共17只鸳鸯、大雁感染死亡。江苏省动物疫病预防控制中心迅速组织相关人员,指导连云港市按照国家相关方案和规范要求,开展现场调查、实验室诊断和应急处置工作。经江苏省动物疫病预防控制中心初诊,国家禽流感参考实验室确诊,诊断为H5N8亚型高致病性禽流感疫情。同时,指导当地政府划定疫点、疫区和受威胁区,封锁相关区域,开展应急监测、紧急流行病学调查、全面消毒等应急处置工作。经果断处置,疫情得到了有效控制,未造成扩散和蔓延。本次疫情提示：野禽疫情的早期发现和及时控制对于降低疫情扩散风险至关重要;林业和农业农村部门的沟通协作要继续加强,日常的禽流感监测力度需要进一步加大,家禽的禽流感疫苗免疫要更加科学,群众的禽流感防控意识要持续提高。