鸡新城疫病毒强毒Q-BS株的分离与鉴定

从2003年10月至2004年6月,在河北、辽宁、山东等地区鸡群中大规模发生以神经症状、肠道出血为主的流行性疾病。本文对从河北省某AA肉鸡场的病死鸡中分离的病毒毒株,经过实验室的系统鉴定,证实该分离株具有血凝性,且可被ND标准阳性血清所抑制和中和,不能被AI(H5亚型与H9亚型)标准阳性血清及阴性血清抑制;该分离株的毒价为109.3ELD50/0.1ml,MDT为57.6h,ICPI为1.89,IVPI为2.62,回归试验鸡的临床表现与自然病例基本一致。试验结果证明,该毒株属于嗜神经型新城疫病毒强毒株,并命名为Q-BS株。     

姜曲海母猪发情周期性腺激素及其子宫受体含量的变化规律

以长白猪为对照,测定了姜曲海母猪发情周期血浆中雌二醇和孕酮及其子宫受体含量。发现发情期血浆雌二醇的峰值为58.3±3.9pg/ml,与长白猪比差异不显著。间情期孕酮的最高水平和平均水平均比长白猪高(23.25±1.36对14.28±1.42ng/ml和18.56±1.42对11.76±0.57ng/ml,P<0.01)。发情期和间情期的细胞质雌二醇受体(CER)分别为 410±30.3和367±14.2fmol/mgDNA,其kd值分别为4.8±0.65和4.0±0.8nmol;细胞核雌二醇受体(NER)分别为1390±195.3和620±28.9fmol/mgDNA,其kd值为6.6±2.1和4.4±1.3nmol;细胞质孕酮受体(CPR)分别为364±56.0和147±46.0 fmol/mgDNA;细胞核孕酮受体(NPR)分别为337±51.8和184±67.0fmol/mgDNA。发情期和间情期子宫NER含量较长白猪高(P<0.05),说明此时姜曲海母猪子宫对雌二醇具有较高的敏感性。     

Apoptosis‐Like Events and In Vitro Fertilization Capacity of Sex‐Sorted Bovine Sperm

This study utilized three staining assays (Annexin V, mitochondrial membrane potential (JC‐1) and TUNEL) for flow cytometric analysis of apoptosis in sex‐sorted sperm from four different bulls (A, B, C and D). Correlations between sperm quality and IVF efficiency were then assessed to determine which assay provided the best prediction of IVF efficiency. The results of the Annexin V assays, as well as measures of viable sperm, early apoptosis, necrotic sperm and mitochondrial membrane potential (?ψm) showed that the sex‐sorted sperm collected from bull A significantly differed from those of the other three bulls (p < 0.05). In addition, the levels of DNA fragmentation in sex‐sorted sperm from bull A were significantly lower than those from bulls B and C (p < 0.05). The percentage of cells reaching the cleavage and blastocyst stages in sex‐sorted sperm from bull A were significantly greater than those from the other bulls (p < 0.05). A significant positive correlation was observed between viable sperm and the percentage of cells at the cleavage or blastocyst stages (p < 0.05). In contrast, a negative correlation was found between early apoptotic sperm and the percentage of cells at the cleavage or blastocyst stages (p < 0.05). In conclusion, these results indicated that the Annexin V assay was the most reliable technique for the prediction of the IVF success of sex‐sorted bovine sperm.     

辽宁省大连市羊群布鲁氏菌病横断面研究

本研究采用横断面研究方法,通过两个阶段的随机抽样检测,结合问卷调查,获得大连市羊群布鲁氏菌病血清流行率及感染风险因素,初步了解了当地养羊场户对布鲁氏菌病防控相关知识的掌握情况和行为实践特点。研究结果表明,大连市羊布鲁氏菌病场群血清流行率为8.89%(95%CI:6.14%~11.63%)。从饲养模式看,调查的6个种羊场均无布鲁氏菌病感染,而商品代饲养场和散养村羊群布鲁氏菌病血清流行率分别为13.33%(95%CI:5.64%~21.03%)和8.21%(95%CI:5.24%~11.17%),差异不显著(X~2=1.93,p=0.170.05)。从饲养品种看,不同品种羊群之间的布鲁氏菌病血清流行率差异也不显著(X~2=0.15,p=0.930.05)。单因素分析结果表明,"与其他养羊场户共用种公羊""产后胎衣丢弃和喂狗""流产物喂狗""与其他养羊场户共用交通工具""近一年羊贩子进羊圈""近一年在交易市场买卖羊"等行为是羊群感染布鲁氏菌病的风险因素,而"购入前检测布鲁氏疾病"是显著的保护性因素。进一步的logistic回归分析表明,"近一年在交易市场买卖羊"(OR=4.91,95%CI:1.57%~15.35%)"流产物处理不当"(OR=1.87,95%CI:1.06%~3.30%)是主要的羊群布鲁氏菌病感染风险因素。"知信行"调查结果表明,大连市养羊从业者对布鲁氏菌病的认知程度较好,说明兽医部门的宣传工作有成效。但从行为实践角度来看,仍有部分养羊场户存有侥幸心理,在日常养殖和生活中不采取降低布鲁氏菌病感染风险的措施。     

浙江地区不同品种紫花苜蓿不同刈割期二茬性状表现

对不同秋眠级别的紫花苜蓿Medicago sativa品种进行适应性试验,研究不同品种不同刈割期株高、分蘖数、根系、茎叶比及生物学产量间的变化,为生产推广提供指导.     

家蝇抗菌肽的研究进展马红霞

从家蝇抗菌肽的分类、结构特点、作用机理、诱变、活性检验以及分子生物学研究等方面介绍了家蝇抗菌肽的研究进展。家蝇抗菌肽独特的作用机理、成熟的诱导、分离纯化技术及其相关基因的克隆、表达等研究成果均为对家蝇抗菌肽进行更深入的研究奠定了基础。采用分子生物学技术有望筛选并制备大量的高效家蝇抗菌肽。     

颗粒人工饲料育对小蚕生长发育的影响

本文探讨了颗粒人工饲料育的饲养方法和饲育环境对小蚕生长发育的影响，结果表明：1－2龄最适给饵量为50mg/头，适宜饲养密度为1.5头／cm^2，增加给饵次数有利于小蚕的生长发育，温度和光照对小蚕的生长发育有显著的影响，以29－30℃黑暗饲育成绩最好。     

促食物质和阻食物质相互作用对家蚕摄食性的影响

以 4龄起蚕取食饲料一定时间后的排粪量为指标 ,探讨了促食性物质和阻食性物质对家蚕摄食性的影响。结果表明 ,将桑叶粉、蔗糖、肌醇等促食物质同时添加到饲料中 ,对家蚕的取食有协同促进作用。脱脂大豆粉、柠檬酸等摄食抑制物质的阻食作用也具有累加性。而将促食物质和阻食物质混合添加时 ,二者表现为相互抑制效应。添加促食剂是减弱或消除阻食性物质的摄食抑制作用的有效途径。     

秦岭野生草坪植物一羊茅的引种驯化

通过对秦岭野生草坪植物一羊茅两个生态型(变种)的引种试验观察,初步发现它们具有绿期长、抗逆性强、繁殖能力强、抗杂草病害等特点,为具有开发前景的优良冷季型草坪植物.     

Fatal infection in human flora-associated piglets caused by the opportunistic pathogen Klebsiella pneumoniae from an apparently healthy human donor

Seventeen out of 24 human flora-associated (HFA) piglets died after oral administration of whole fecal flora from an apparently healthy human donor. The bacteria isolated from the organs of the infected piglets were identified as Klebsiella pneumoniae by bacteriological and biochemical tests and 16S rRNA gene sequence analysis. The identical K. pneumoniae strain was also isolated from the donor's fecal flora. All three neonatal piglets inoculated with K. pneumoniae from the donor's fecal flora developed severe diarrhea, with 2 eventually dying. This strongly suggests that the opportunistic pathogen K. pneumoniae from the human donor caused the fatal infection in the HFA piglets. The results underscore the importance of safety evaluation of the human donor's fecal flora for HFA piglet development.