新城疫活疫苗对控制鸡大肠杆菌病的效果观察

为了研究鸡新城疫活疫苗紧急免疫控制鸡大肠杆菌病的效果,通过大肠杆菌人工感染30日龄蛋鸡,待出现病症后,紧急免疫新城疫La-sota弱毒苗(Ⅳ系)4羽份.免疫后5～17 d,通过血凝抑制试验测定血清新城疫抗体水平,试验组新城疫抗体水平逐步提高,对照组抗体略有下降,免疫后17 d两组抗体水平差异显著(P＜0.05);对照组...     

乙型脑炎病毒荧光定量PCR的建立及对病毒体外复制动态的研究

根据乙型脑炎病毒(JEV)NS3基因保守序列设计并合成一对引物,以构建的重组质粒作为阳性标准品,建立了一种敏感、特异、重复性好的快速检测JEV的SYBR Green I荧光定量PCR方法.该方法在1.92×108～1.92×101拷贝/μL范围内具有良好的线性关系,可检测到初始模板中19拷贝/μL的病毒核酸,敏感性是常规RT-PCR方法的10倍;检测时间缩短了50％,该方法不与其它猪源病毒发生交叉反应;在重复性试验中,批间、批内变异系数均小于1.2％.应用本方法对JEV在BHK-21细胞上繁殖滴度进行定量检测,绘制JEV在BHK-21细胞上的一步生长曲线,并与TCID50方法绘制的复制动态曲线进行比较.结果显示,两种方法测定的JEV在BHK-21细胞上的复制动态具有一定的平行关系,对于制备灭活疫苗而言,荧光定量PCR方法更快速和敏感,所测得的抗原含量更精确,有利于企业机动灵活地安排生产.     

Indium-111 labeled vitamin B12 imaging of a ciliary adenoma with concurrent grade 2 soft tissue sarcoma of the leg in a Labrador Retriever

An 11-year-old, male castrated, Labrador Retriever was evaluated for the presence of rapidly growing concurrent leg and intraocular masses. Metastasis was noted in the chest at time of initial presentation. Indium-111 labeled vitamin B12 imaging was performed, and there was significant uptake by both primary tumors and the lung metastases. Enucleation and amputation were performed for palliative relief. The leg mass was a grade 2 soft tissue sarcoma and the ocular mass a ciliary adenoma. The dog remained symptom-free for approximately 10 weeks before developing signs of respiratory distress. He was euthanized 12 weeks after initial presentation, and there was diffuse infiltration of the lungs with metastatic sarcoma. Indium-111 labeled vitamin B12 imaging identified a ciliary adenoma in this case and may provide a useful differentiation technique for evaluation of intraocular and retrobulbar masses if it can be demonstrated that there is differential uptake between inflammatory or infectious conditions and neoplasia.     

细胞松弛素B浓度对小鼠卵母细胞去核效果的影响

目的　探讨细胞松弛素 B浓度对小鼠卵母细胞去核效果的影响。方法　常规超排 KM小鼠获卵母细胞 ,将有明显第一极体的卵母细胞放入含有 5× 10 - 3、1× 10 - 2 、2× 10 - 2 g/ L CB的成熟培养液中孵育 15 min,采用盲吸法去核 ,去核后的卵母细胞放入含 5× 10 - 3g/ L Hoechst33342的成熟培养液中染色 15 min,在荧光显微镜下检查去核的效率。结果　 CB组去核率可达 88.2 % ,而对照组去核成功率仅达 2 9.7% ,两者的去核效果统计学上有显著差异 ;同时 CB的浓度过高会影响去核的效果 ,使卵母细胞的破溃率升高。结论　 CB有利于去核 ,同时卵胞膜可以借助磷脂双层的游动性而很快得到修复 ;高浓度的 CB对卵胞膜作用过于强烈 ,细胞骨架严重破坏 ,磷脂双层结构的弹性和粘性减弱 ,修复能力降低 ,影响胚胎的构建。     

桑花叶病病原及化学药剂治疗的研究

桑花叶病的症状种类较多，是由多种植物病原病毒寄生引起发病，其中有一种是暂定名为桑斑块花叶病，其症状主要是形成退绿斑块花叶，畸形叶或叶形变长。病原病毒为球形，直径25～30nm，主要通过嫁接传病。化学药剂吖橙对此病有明显抑制作用，从而使病桑树康复并增产。     

Performance of using opposing homozygotes for paternity testing in Japanese Black cattle

Genome-wide single nucleotide polymorphism (SNP) markers in Japanese Black cattle enable genomic prediction and verifying parent–offspring relationships. We assessed the performance of opposing homozygotes (OH) for paternity testing in Japanese Black cattle, using SNP genotype information of 50 sires and 3,420 fattened animals, 1,945 of which were fathered by the 50 genotyped sires. The number of OH was counted for each sire–progeny pair in 28,764 SNPs with minor allele frequencies of ≥0.05 in this population. Across all pairs of animals, the number of OH tended to increase as the pedigree-based coefficient of relationship decreased. With a threshold of 288 (1% of SNPs) for paternity testing, most sire–progeny pairs were detected as true relationships. The frequency of Mendelian inconsistencies was 2.4%, reflecting the high accuracy of pedigree information in Japanese Black cattle population. The results indicate the utility of OH for paternity testing in Japanese Black cattle.     

潮霉素B预混剂的临床驱虫试验研究

为了解潮霉素B预混剂临床驱除绦虫线虫的有效性和给药时间的合理性,依据兽药临床试验规范,试验选择了蠕虫自然感染皖西麻黄鸡824只,按要求随机分为3组,分别为潮霉素B预混剂治疗组284只,芬苯哒唑粉对照药物组284只,不治疗的感染对照组256只,试验周期根据临床治疗效果确定。结果显示,潮霉素B预混剂,推荐剂量10 mg/kg混饲,连续饲喂21 d,对鸡蛔虫和绦虫的粗计驱虫率分别为63%和26%,表现明显的驱除蛔虫作用(P0.05),连续饲喂42 d,对鸡蛔虫和绦虫的粗计驱虫率分别为100%和-13%,驱蛔虫效果极显著(P0.01);对照药物芬苯哒唑粉,50 mg/kg混饲,连续饲喂6 d,对鸡蛔虫和绦虫的粗计驱虫率分别为100%和44%,同样具有极显著的驱除蛔虫作用(P0.01),本试验中2种药物的驱蛔虫效果相当,对绦虫的驱除作用不明显(P0.05)。潮霉素B预混剂10 mg/kg混饲,连续饲喂42 d,可以驱净鸡蛔虫的感染,但对鸡绦虫感染无明显的驱除作用。     

Encephalitozoon cuniculi–Associated Equine Encephalitis: A Case Report

A case of encephalitis of unknown origin in the horse was investigated. Postmortem examination findings revealed a nonsuppurative granulomatous meningoencephalitis in the right hemisphere of the cerebral cortex. Testing for West Nile virus, equine herpes virus, equine infectious anemia, Toxoplasma gondii, Neospora caninum, and Sarcocystis neurona were negative. The horse had a titer for Encephalitozoon cuniculi, and sections from the affected area of the brain tested positive for the organism using both polymerase chain reaction (PCR) and immunohistochemistry. Amplicons generated using PCR were sequenced, and E. cuniculi genotype II was identified. This is the first case of E. cuniculi genotype II associated with encephalitis in the horse.     

Involvement of the ERK1/2 MAPK pathway in insulin-induced S6K1 activation in avian cells

In mammals, insulin regulates S6K1, a key enzyme involved in the control of protein synthesis, via the well-documented phosphoinositide-3'kinase (PI3K) pathway. Conversely, S6K1 is activated by insulin in avian muscle despite the relative insulin insensitivity of the PI3K pathway in this tissue. Mitogen-activated protein kinase (MAPK) cascade is another insulin sensitive pathway. The aim of this study was to explore the potential involvement of the ERK1/2 MAPK pathway in the control of p70 S6 kinase (S6K1) in avian species. Firstly, we characterized ERK1/2 MAPK in various chicken tissues. ERK2 was the only isoform detected in avian species whatever the tissue studied. We also showed that ERK2 is activated in vivo by insulin in chicken muscle. The regulation and the role of ERK2 in insulin signaling were next investigated in chicken hepatoma cells (LMH) and primary myoblasts. Insulin stimulation led to ERK2 and S6K1 phosphorylation, and concomitantly increased kinase activity. U0126, an inhibitor of the ERK MAPK pathway, completely abolished insulin-induced S6K1 phosphorylation and activity in chicken myoblasts, whereas its effect was only partial in LMH cells. In conclusion, these results show that ERK1/2 MAPK is involved in the control of S6K1 by insulin in chicken cells, particularly myoblasts.