Evaluation of a competitive ELISA for antibody detection against avian influenza virus

Active serologic surveillance is necessary to control the spread of the avian influenza virus (AIV). In this study, we evaluated a commercially-available cELISA in terms of its ability to detect AIV antibodies in the sera of 3,358 animals from twelve species. cELISA detected antibodies against reference H1- through H15-subtype AIV strains without cross reactivity. Furthermore, the cELISA was able to detect antibodies produced following a challenge of the AIV H9N2 subtype in chickens, or following vaccination of the AIV H9 or H5 subtypes in chickens, ducks and geese. Next, we tested the sensitivity and specificity of the cELISA with sera from twelve different animal species, and compared these results with those obtained by the hemagglutination-inhibition (HI) test, the "gold standard" in AIV sera surveillance, a second commercially-available cELISA (IZS ELISA), or the agar gel precipitation (AGP) test. Compared with the HI test, the sensitivities and specificities of cELISA were 95% and 96% in chicken, 86% and 88% in duck, 97% and 100% in turkey, 100% and 87% in goose, and 91% and 97% in swine, respectively. The sensitivities and specificities of the cELISA in this study were higher than those of IZS ELISA for the duck, turkey, goose, and grey partridge sera samples. The results of AGP test against duck and turkey sera also showed significant correlation with the results of cELISA (R-value >0.9). In terms of flock sensitivity, the cELISA correlated better with the HI test than with commercially-available indirect ELISAs, with 100% flock sensitivity.     

蝴蝶兰不同品种表型性状遗传多样性分析

以72份蝴蝶兰品种为研究对象,对其叶片、花梗和花器官相关的34个表型性状进行测定与评价,通过表型多样性分析、聚类分析和主成分分析等方法,探讨其种质资源表型性状的遗传多样性。结果表明：72份蝴蝶兰品种的绝大多数性状呈现变异丰富、类型多样的特性,数量性状遗传多样性变异范围为16.39%～157.36%,质量性状Shannon−Wiener多样性指数范围为0.38～1.32,其中叶片的数量性状变异程度较低,但其质量性状的多样性水平较高;R型聚类分析将34个性状分为3个大类,第I类群包含了花部和叶部性状,表明花与叶的表型联系较紧密,第II类群和第III类群包含花序长、最长叶长、植株大小和花序梗长,表明这4个表型性状呈独自进化关系; Q型聚类分析将72份蝴蝶兰种质资源分为4大类,其中第II类可细分为7个亚类群,II−1、II−2亚类群可作为大花和中花育种的亲本,II−3、II−4、II−5和II−7亚类群可作为小花育种的亲本,II−4亚类群可作为香花育种的亲本,同时蝴蝶兰‘JB5342’‘JB5184’‘JB5541’‘JB3697’‘安娜’和‘JB5725’等品种与多数供试蝴蝶兰品种遗传距离较远,可作为重要亲本参考。主成分分析表明,花宽、花瓣长、花瓣宽、萼片长、花长和萼片宽的特征向量绝对值较高,是造成蝴蝶兰表型变异的主要因素。     

影响新疆阿克苏地区棉花质量的主要成因及提升对策

随着新疆阿克苏地区机采棉面积的激增,棉花质量出现下降,存在颜色级下降、长度偏短、成熟度不够等现象。为全面了解阿克苏地区棉花纤维品质变化情况及成因,阿克苏地区农业农村局组织有关人员深入植棉县（市）种子管理站、种业企业、棉花加工企业、棉纺企业、种植大户开展调研。结合调研分析,认为影响棉花质量的主要因素是品种、种植管理、采收、收购和加工工艺等,并从积极发挥政策引导作用,加大优质棉花品种选育与管理,开展配套生产技术研究与规范棉花种植管理,规范棉花采收、加工行为,强化棉花质量监督检查,合力打造品牌棉花,促进信息互联互通等方面提出了相应对策,以期对提升该地区棉花质量起到指导作用。     

几种中微量元素肥料对烤烟产量及品质的影响

2011年,在吉林省大安市、洮南市和镇赉县分别进行了大田烤烟,锰、硼、钼、锌和镁肥的施肥量和施用方法的试验研究。试验结果表明:在锰、硼、钼、锌和镁等中微量元素有效含量缺乏的烟田中,增施适量的中微肥,能够促进烤烟的营养均衡并在此基础上促进其生长;能够提高土壤和叶片中相应的中微量元素含量;烤烟的经济效益也随之得到提高。从试验长势看,所有试验中微肥都比对照好,喷施比基施表现要好,基施中硼、钼、锌、镁表现比较好,喷施中硼、钼、镁、钾+钼、钾+锌表现最好;从烘烤质量上看,不论基施的还是喷施的钼都表现得最好。     

我国生猪生产的波动性研究

本文针对生猪产量数据存在的问题,对肉类市场放开至第一次农业普查期间的生产数据进行了调整,在此基础上运用趋势分解法描述了改革开放后我国生猪生产的波动情况,进而对历史数据所描述的波动特征表示置疑,认为我国生猪生产存在明显的周期性,最后提出当前我国生猪生产急需采取的一些必要措施,以建立生猪供给安全长效机制。     

用重组核衣壳蛋白ELISA检测PRRSV抗体的研究

ＰＲＲＳＶ重组Ｎ蛋白ＥＬＩＳＡ检测人工感染猪血清７５份,与ＩＤＥＸＸ公司ＥＬＩＳＡ试剂盒及ＩＦＡ的符合率分别为９７．３％和１００％。检测疫苗免疫猪血清,阳性率１００％。在免疫后６ｄ就能检出抗体,比ＩＦＡ敏感。检测８５份我国田间猪血清,阳性率１８．８％。     

低成本省力化栽桑技术的研究进展

我国已育成了若干适合条桑育,适于扦插的桑品种及适于种子直播的杂交桑,为建立高密度低成本桑园打下了基础。推广了直接用袋接体,硬枝扦插和杂交种直接建园和初试了中晚秋条桑收获技术。今后的研究方向是选育发根性强,高产优势,适合条桑收获的桑树品种及以条桑收获为主的提高劳动生产率的栽培技术。     

青皮种子主要储藏条件的研究Ⅰ.种子含水量与测控

水分是影响青皮(Vatica astrotricha Hance)种子活力最关键的内在因素,其中种胚含水量是决定因素。用含水量27—29％椰糠控制种胚含水量在50—52％,也就是控制种子含水量在30—36％,维持种子一定的呼吸强度(32℃下测定为50—60 O_2μl/g·h),种子活力保持最高,能延长寿命。找出了储藏中种子安全含水量的最佳点,此点处于安全含水量下限的内缘,可利用种子本身果翅与种子或大小种子之间含水量的内在关系来测定。这种测定方法准确、快速又简便。可考虑作为确定“顽拗型”种子安全含水量下限的新捷径。     

Altered pharmacokinetics of enrofloxacin in experimental models of hepatic and renal impairment

We investigated the effects of hepatic and renal impairment on the pharmacokinetics of enrofloxacin in Sprague-Dawley rats. Experimental hepatic and renal failure were induced by carbon tetrachloride (CCL₄) and 5/6 nephrectomy, respectively. After intravenous dosing of enrofloxacin (10 mg/kg), plasma concentrations of enrofloxacin were measured using liquid chromatograph/mass spectrometry. There was no significant effect of hepatic impairment on enrofloxacin pharmacokinetics. However, renal impairment markedly prolonged elimination half life (t_1/2λz) of enrofloxacin (P < 0.05), comparing with respective control. Total body clearance (Cl_b) and volume of distribution at steady state (V_ss) were significantly decreased (P < 0.05) by renal impairment. In conclusion, these results suggested that renal impairment could affect the pharmacokinetics of enrofloxacin.     

贵州天然豆科牧草——窄叶野豌豆的引种与驯化

对采自贵州省册亨县、三都县的窄叶野豌豆野生种进行了引种驯化。结果表明：其产草量中等，鲜草３７．５～４５ｔ／ｈｍ２，草质优良；生育期短，早熟；种子产量高，收纯净种子５００～６００ｋｇ／ｈｍ２。适合在我国南方中亚热带地区同水稻、玉米轮作，也可作为农田填闲作物栽培