诺氟沙星与牛血清白蛋白及卵清蛋白结合物的合成

采用碳二亚胺法制备诺氟沙星与牛血清白蛋白（BSA）的结合物，作为诺氟沙星酶联免疫用的免疫原。经紫外光谱法测定，每分子牛血清白蛋白连接的诺氟沙星分子数为16.1个。分别用碳二亚胺法和混合酸酐法制备诺氟沙星与卵清蛋白（OA）的结合物，作为诺氟沙星酶联免疫测定用的包被抗原。经紫外光谱法测定，每分子卵清蛋白连接的诺氟沙星分子数分别为5.8和1.9个。     

不同品系北京鸭血清前白蛋白多态性的研究

应用聚丙烯酰胺凝胶电泳法研究了北京鸭的血清前白蛋多态性，在2个位点观察到多态，Pam位点为单态，在Pas位点发现有5种表现型，它们的频率是：Pas2-2O 26．67％，Pas1-2为12％，Pas2-1为45.33%,Pas1-1为2．67％，Pas2-0为13．33％，在Paf位点发现有4种表现型，它们的频率是：PafF为29．33％，PafS为41．33％，PafFS为10．67％，Paf0为18．67％，并计算了它们的基因频率，群体平均杂合度和遗传距离，遗传分析表明，樱桃谷鸭和奥白星鸭遗传结构相似，而与B系北京鸭遗传结构有明显差异。     

鱼体内性类固醇激素水平与催产药物相关性研究

研究怀卵大鳞副泥鳅(Paramisgurnus dabryanus)用药后亲鱼血清、卵液性激素含量变化,探讨了药物组合和变化间的相关性。结果表明,GnRH-A及其配伍注射后,泥鳅血清中雌雄激素、卵液中孕激素含量在排卵前增加,呈明显的组合—效应关系;表明催产药物可引起血清、卵液性激素含量变化,并且这一变化有一定的规律性,可能会成为繁殖药物筛选的重要指标。     

高铜日粮对断奶仔猪血清及组织中铜、铁、锌沉积的影响

选用60头(28±2)日龄“长×大×定”三元杂交断奶仔猪,按体重和性别随机分成3组,每组20头。Ⅰ组仔猪饲喂基础日粮;Ⅱ组仔猪在断奶后14 d内饲喂基础日粮+250 mg.kg-1铜(CuSO4.5H2O),然后再饲喂基础日粮;Ⅲ组仔猪饲喂基础日粮+250 mg.kg-1铜(CuSO4.5H2O)。试验期28 d。分别于断奶后0、7、14、28 d经前腔静脉采血,用原子吸收光谱仪检测血清中铜、铁、锌水平。试验结束时,每组选5头仔猪放血致死,取心、肝、肾、脾、脑组织,测定铜、铁、锌含量。结果表明,在饲料中添加高铜,可显著提高断奶仔猪的平均日增重和日采食量,降低料重比和腹泻率。仔猪断奶后,血清铜、锌水平下降,高铜日粮显著提高肝、肾、脑和血清铜的含量,降低肝、脾和血清中铁的含量。     

龙井地区犬附红细胞体病流行情况调查

对延边大学农学院动物医院就诊及龙井屠宰场屠宰的犬用血液压滴标本、血涂片染色镜检、差速离心浓集法进行附红细胞体检查，观察其形态，进行流行病学调查。结果表明该地区犬附红细胞体感染率很高，用血液压滴标本法检出犬附红细胞体感染率达100％，红细胞的附红细胞体感染率最高达94．4％，平均红细胞感染率达70．3％。     

河北省猪附红细胞体病的流行病学调查

应用血液压片镜检法对河北省猪附红细胞体病进行了检测,研究猪附红细胞体病在河北省的发病情况和感染率.结果表明:共检测猪血样1 613份,其中阳性血样1 480份,感染率达91.8%.     

陕西关中地区鸡产蛋下降综合征的调查

对陕西省宝鸡市等９个市（县、区）的３５个ＥＤＳ－７６非免疫鸡群和某大型养鸡场的１４个ＥＤＳ－７６免疫鸡群进行了流行病学调查，并采集５０５份血清（其中非免疫鸡群３２３份，免疫鸡群１８２份）用微量血凝抑制试验进行了ＥＤＳ－７６抗体监测。首次确定陕西省确有ＥＤＳ－７６的发生与流行，其非免疫鸡群的阳性率为３５．０９％，有６０％的鸡群受到感染，发病情况和病程与国内外报道的基本一致。调查结果还表明：红壳蛋鸡比白壳蛋鸡对该病更为易感；疫苗注射对该病的发生具有很好的预防作用     

云南省新发猪圆环病毒3型感染状况调查与全基因进化分析

为了解猪圆环病毒3型(PCV3)在云南省不同地区猪群中的流行情况,针对PCV3基因保守区域设计特异性引物,优化反应条件,建立PCR快速检测方法,并采用该方法对采自云南省不同地市431份样品进行检测,将获得的部分毒株全基因序列进行遗传进化分析。结果显示:本研究成功建立了一种快速、特异和灵敏的PCV3检测方法;云南省12个地(市)29县(区)中,8个地(市)12个县(区)检测出阳性样品;431份样品中有43份PCV3阳性样品,阳性率为9.98%;获得的3株PCV3全基因组序列与参考毒株之间的核苷酸同源性为98.6%~99.5%,进化树显示3株云南毒株形成一个小的进化分支,属于PCV3a基因型。本研究结果表明,PCV3在云南省多个地区呈一定的流行趋势,流行毒株以PCV3a基因型为主,有必要进一步开展云南地区PCV3流行病学调查,并提出防控对策。     

Spatial association between primary Middle East respiratory syndrome coronavirus infection and exposure to dromedary camels in Saudi Arabia

Middle East respiratory syndrome coronavirus (MERS‐CoV) is an emerging zoonotic disease. Exposure to dromedary camels (Camelus dromedaries) has been consistently considered the main source of primary human infection. Although Saudi Arabia reports the highest rate of human MERS‐CoV infection and has one of the largest populations of dromedary camels worldwide, their spatial association has not yet been investigated. Thus, this study aimed to examine the correlation between the spatial distribution of primary MERS‐CoV cases with or without a history of camel exposure reported between 2012 and 2019 and dromedary camels at the provincial level in Saudi Arabia. In most provinces, a high proportion of older men develop infections after exposure to camels. Primary human infections during spring and winter were highest in provinces characterized by seasonal breeding and calving, increased camel mobilization and camel–human interactions. A strong and significant association was found between the total number of dromedary camels and the numbers of primary camel‐exposed and non‐exposed MERS‐CoV cases. Furthermore, spatial correlations between MERS‐CoV cases and camel sex, age and dairy status were significant. Via a cluster analysis, we identified Riyadh, Makkah and Eastern provinces as having the most primary MERS‐CoV cases and the highest number of camels. Transmission of MERS‐CoV from camels to humans occurs in most primary cases, but there is still a high proportion of primary infections with an ambiguous link to camels. The results from this study include significant correlations between primary MERS‐CoV cases and camel populations in all provinces, regardless of camel exposure history. This supports the hypothesis of the role of an asymptomatic human carrier or, less likely, an unknown animal host that has direct contact with both infected camels and humans. In this study, we performed a preliminary risk assessment of prioritization measures to control the transmission of infection from camels to humans.