水貂绿脓杆菌（PASD03株）鞭毛蛋白的提取与分析

本试验以水貂绿脓杆菌PASD03株为研究对象,对其鞭毛蛋白的提取方法进行研究,分别通过酸裂解、差速离心以及酸裂解结合机械振荡三种方法,用（NH4）2SO4盐析来获得鞭毛蛋白,采用垂直板聚丙烯酰胺凝胶电泳（SDS-PAGE）对提取的绿脓杆菌鞭毛蛋白进行分离纯化,并进行电镜鉴定。结果显示：成功分离出水貂绿脓杆菌的鞭毛蛋白,获得了绿脓杆菌鞭毛蛋白的初提液.绿脓杆菌鞭毛蛋白经SDS-PAGE提示纯化的鞭毛蛋白为一条相对分子质量（Mr）为53×103蛋白带,透射电镜（SEM）观察发现该鞭毛蛋白呈丝状。结论：经酸裂解法并结合机械振荡和硫酸铵沉淀法简便、耗时短、纯度高、产量高,适用于绿脓杆菌鞭毛蛋白的提取。     

甘南玛曲七种主要饲草营养价值比较

对甘南玛曲七种主要饲草的干草产量、高度、常规养分(粗蛋白质、酸性洗涤纤维、粗脂肪、粗灰分、无氮浸出物、钙、磷)进行测定,用灰色关联度法对其营养价值进行评价.结果表明:天然草地干草产量为2882kg/hm2,比新疆大叶苜蓿、甘农l号苜蓿、红豆草和箭(苫)豌豆高,比绿麦、燕麦和垂穗披碱草低,牧草营养价值为甘农1号苜蓿＞绿麦＞箭(苫)豌豆＞垂穗披碱草＞新疆大叶苜蓿＞燕麦＞天然草地＞红豆草.     

RADIOGRAPHIC FINDINGS IN DOGS WITH SPONTANEOUS PULMONARY THROMBOSIS OR EMBOLISM

Thoracic radiographs of 21 dogs with necropsy-confirmed pulmonary thrombosis or embolism (PTE) were reviewed. Two major lung patterns were seen: (1) regional oligemia, giving the impression of a hyperlucent zone; (2) alveolar pulmonary infiltrate, indicating hemorrhage or infarction. Hemorrhage and infarction could not be differentiated radiographically. Other common findings were attenuation or loss of visualization of a lobar artery or lobar vein and pleural effusion, particularly with infarction and cardiac disease. PTE was often associated with renal disease (glomerulonephritis, amyloidosis), septic processes, pancreatitis, systemic venous or right heart thrombosis, cardiac insufficiency, and hypercorticism.     

达乌里胡枝子花粉萌发特性研究

为揭示达乌里胡枝子(Lespedeza daurica)花粉的育性并为其花粉活力检测提供一种高效方法,本试验以达乌里胡枝子新鲜花粉为试验材料,采用液体培养基,研究了蔗糖、硼酸、氯化钙浓度、采样时间、温度、光照和培养时间等因素对花粉离体萌发和花粉管生长的影响.试验结果表明:单因素试验中,适宜花粉萌发的培养基配方为20 g...     

哺乳期幼驼与成年母驼粪便菌群多样性分析

【目的】探究准噶尔双峰驼哺乳期幼驼和成年母驼粪便菌群结构组成及多样性变化,为幼驼肠道健康发育提供重要依据。【方法】选取6～7岁体况相近的健康成年母驼12峰,以及出生日期相近(3月龄)的哺乳期母幼驼12峰,母驼与幼驼在相同饲养环境下饲养。采用直肠取粪法采集粪样,用于粪便内容物细菌16S rDNA的V3-V4区测序,并对测序数据进行相应分析。【结果】母驼粪便菌群Chao1和Shannon指数均显著高于幼驼(P<0.05);在门水平上,母驼和幼驼粪便中位于前十的菌均为厚壁菌门、拟杆菌门、疣微菌门、变形菌门、软壁菌门、螺旋体门、TM7、放线菌门、蓝藻菌门和纤维杆菌门,其中幼驼粪便中变形菌门和软壁菌门丰度均极显著高于母驼(P<0.01);在科水平上,母驼与幼驼粪便中位于前十的菌均为瘤胃球菌科、消化链球菌科、毛螺菌科、梭菌科、克里斯滕森菌科、理研菌科、疣微菌科、拟杆菌科、艰难杆菌科和普雷沃氏菌科,其中母驼粪便中消化链球菌科和梭菌科的丰度均极显著高于幼驼(P<0.01),而幼驼粪便中毛螺菌科的丰度极显著高于母驼(P<0.01);在属水平上,母驼与幼驼粪便中位于前十的菌属均为梭...     

Current knowledge about the processes of luteolysis and maternal recognition of pregnancy in camelids

Camelids have many unique reproductive features that considerably differ from those of other domestic species. Females are induced ovulators with subsequent development of a corpus luteum (CL) with a short lifespan. Plasma progesterone concentration starts to increase on day 4, peaks on day 8–9 and, in non-pregnant animals, basal concentration is reached around day 10–11 post-induction of ovulation. Luteolytic pulses of prostaglandin F_2α (PGF_2α) are firstly detected on day 7 or 8 (approximately on day 5–6 after ovulation), with maximal luteolytic peaks observed between days 9 and 11 post-mating, in coincidence with a high endometrial expression of cyclooxygenase 2, a limiting enzyme in prostaglandins synthesis. Unlike other species, oxytocin seems not to be involved in the luteolytic process in these species. The CL is the main source of progesterone secretion, and its function is required to support pregnancy. Despite constant research efforts, aspects of reproduction and maternal recognition of pregnancy in camelids remain not fully understood. A transient decrease and subsequent recovery in plasma progesterone concentration are observed after day 9 post-mating in pregnant animals in association with a pulsatile release of PGF_2α and a transitory decrease in CL vascularization. Thus, embryo recognition should occur between days 8 and 12 post-mating. In camels, conceptus tissues exhibit aromatizing activity with the capacity to synthesize large amounts of oestradiol. Similarly, llama blastocysts secrete oestradiol-17β during the preimplantation stage, with a higher production during the elongation period. An increase in the endometrial expression of oestrogen receptor α is also observed on day 12 post-mating. All these evidences suggest that oestrogen could be the signal released by the embryo at the time of its recognition in camelids. Besides, nearly 98% of pregnancies are carried out in the left horn. A decrease in the endometrial expression of mucin 1 and 16 genes has been reported, suggesting that these changes are crucial for successful embryo implantation; however, no differences have been observed between horns. Thus, maternal recognition of pregnancy in camelids is a particularly complex process that must occur in a concise time to allow the rescue of the CL and embryo survival.     

曲拉通和硝酸混合溶液直接提取快速测定草鱼中铅含量

为建立快速测定草鱼中铅含量的方法,通过分析曲拉通和硝酸混合溶液浓度、提取时间、称样定容体积比例等因素的影响,以及基体改进剂的使用效果,确定了草鱼中铅元素提取测定的最佳条件。验证结果显示：采用曲拉通和硝酸混合溶液提取草鱼中铅元素方法的提取率为86.5%～95.6%,加标回收率为91.5%～95.6%,精密度均小于4.0%,检出限和定量限分别为0.011和0.032 mg/kg,满足了国家标准GB 5009.12—2017第一法石墨炉原子吸收光谱法的要求。与国家标准方法比较,本研究建立方法的样品前处理时间从4～12 h缩短至0.2 h内,酸试剂用量从湿法消解的7～12 mL减少至1～2 mL;前处理过程无需高温消解,无需其他前处理设备,避免了样品污染和待测元素损失,实现了降低分析成本以及保护环境和试验人员的目的。结果表明,该方法是一种简单、准确、绿色、快速测定草鱼中铅含量的方法,尤其适合大量样品检测。     

结核杆菌多位点环介导等温扩增检测方法的建立

为建立一种快速、高敏感、高特异、鉴别结核分枝杆菌和牛分枝杆菌的方法,本研究根据大多数致病性结核分枝杆菌共有序列esat-6,结核分枝杆菌和牛分枝杆菌gyrB共有特异性序列,以及结核分枝杆菌种特异序列mtp40设计6对特异性引物对痰液中的结核分枝杆菌进行检测,并与鉴别培养基分离培养结果以及常规PCR鉴定结果进行比较。实验结果表明,建立的LAMP检测方法具有很高的特异性。可区分致病性结核分枝杆菌和非致病结核分枝杆菌,也可鉴别结核分枝杆菌和牛分枝杆菌。LAMP检测技术的灵敏度比经典PCR技术高100倍左右,可检测到7拷贝/反应。另外,用3种方法同时检测样品发现,LAMP与细菌培养的符合率为90.91%,LAMP与常规PCR检测结果的符合率为100%。LAMP检测方法可以在流行病学调查及现场快速诊断方面广泛应用,并为临床治疗提供依据。     

Evaluation of infectivity and transmission of different Asian foot-and-mouth disease viruses in swine

Most isolates of foot-and-mouth disease virus (FMDV) display a broad host range. Since the late 1990s, the genetic lineage of PanAsia topotype FMDV serotype O has caused epidemics in the Far East, Africa, the United Kingdom, France, the Netherlands, and numerous other countries throughout Europe and Asia. In contrast, there are several FMDV isolates that exhibit a more restricted host range. A Cathay topotype isolate of FMDV serotype O from the 1997 epizootic in Taiwan (O/TAW/97) demonstrated restricted host specificity, only infecting swine. Methods used to evaluate infectivity and pathogenicity of FMDV isolates in cattle are well-documented, but there has been less progress studying transmission and pathogenicity of FMDV isolates in pigs. In previous studies designed to examine pathogenicity, various chimeric viruses derived from O/TAW/97 were intradermally inoculated in the heel bulb of pigs. Subsequent quantitative scoring of disease and evaluation of virus released into nasal secretions and blood was assessed. Here we prove the usefulness of this method in direct and contact inoculated pigs to evaluate infectivity, pathogenicity and transmission of different Asian FMDV isolates. Virus strains within the Cathay topotype were highly virulent in swine producing a synchronous disease in inoculated animals and were efficiently spread to in-contact naive pigs, while virus strains from the PanAsia topotype displayed more heterogeneous properties.     

自制中药颗粒剂对腹泻仔猪小肠黏膜病理结构及养分消化率的影响

为了研究自制中药复方颗粒剂对腹泻仔猪小肠黏膜组织结构和营养消化率的影响,试验选用人工感染大肠埃希菌引起腹泻的28日龄断奶的杜长大仔猪36头,随机均分为2组,每组3个重复,每个重复6头。抗生素治疗组在饮水中添加盐酸林可霉素2.0 m L/头饮水,2次/d,连续5 d;中药复方颗粒剂治疗组在饮水中添加2.0 g/头饮水,2次/d,连续5 d。分别于用药后14 d时,每组每个重复随机抽取1头屠宰,无菌采集小肠黏膜,通过石蜡切片和HE染色观测小肠黏膜病理组织学变化。其余仔猪继续饲养14 d,采用内源指示剂法进行消化试验。结果显示,小肠黏膜组织结构:中药复方颗粒剂治疗组小肠黏膜除有少量出血外,未发现明显病理变化。抗生素治疗组小肠黏膜脱落,有广泛充血、出血;黏膜上皮细胞变性坏死;嗜酸性粒细胞浸润,有大量以淋巴细胞杯状细胞为主的炎性细胞浸润;微绒毛排列紊乱、脱落;细胞受损严重,线粒体等细胞器结构异常。养分消化率:对于有机物质、磷的消化率,各组之间无显著差异,中药复方颗粒剂治疗组对钙的消化率为57.10%,显著高于抗生素治疗组(56.10%),并与健康仔猪组(57.40%)差异不显著。中药复方颗粒剂治疗组对粗蛋白质的消化率为79.30%,显著高于抗生素治疗组(78.50%),并与健康仔猪组(79.20%)差异不显著。中药复方颗粒剂治疗组对粗纤维的消化率为48.30%,极显著高于抗生素治疗组(46.10%),并与健康仔猪组(48.20%)差异不显著。中药复方颗粒剂治疗组对粗脂肪的消化率为63.40%,极显著高于抗生素治疗组(62.10%),并与健康仔猪组(63.60%)差异不显著。结论:抗生素治疗仔猪腹泻造成小肠黏膜明显的病理变化和功能障碍,而中药治疗有利于仔猪小肠黏膜组织结构的修复,并能显著提高小肠的养分消化率。为防治仔猪腹泻、提高仔猪的生长性能提供依据。