浅谈鸡球虫病的免疫

鸡球虫病是一种危害性较大的肠道寄生虫病,多发于3个月龄以内的仔鸡.尤以15～45日龄的雏鸡最易感染,近年来,球虫疫苗应用,使工厂生产的养鸡场在鸡球虫病控制方面取得显著成绩.笔者就鸡球虫病免疫在生产实践中的应用,作肤浅论述.     

宿主域扩大的重组救活昆虫杆状病毒表达载体的构建及外源基因的表达

通过克隆的家蚕核多角体病毒解旋酶基因DNA与重组救活可线性化的苜蓿尺蠖核多角体病毒基因工程载体病毒 (BacPAK6 )DNA在昆虫细胞中发生重组 ,经累代筛选获得了既可感染家蚕又可感染秋粘虫细胞Sf 2 1的宿主域扩大的昆虫杆状病毒表达载体 (HyBacPAK6 )。HyBacPAK6DNA经Bsu36Ⅰ酶切后与含植酸酶基因的转移载体pVL1393 phy在家蚕细胞中重组后 ,通过蓝白斑筛选发现重组率可达 90 %以上。然而以杂交病毒为载体的外源基因表达量仅为以BmNPV为载体病毒的表达量的 2 0 %左右。分析认为HyBacPAK6可用于表达一些对蚕体有害的外源基因。     

体外评定酸化剂作用效果的方法探讨

文章主要论述了体外法评定酸化剂作用效果的指标和评定方法。     

AFLP分子标记对9份狗牙根材料的鉴定分析

狗牙根(Cynodon dactylon)是全球最重要、品种最丰富的暖季型草坪草种之一,种或品种间形态相近,采用传统形态学和田间小区试验等方法难以作出鉴定,本试验利用AFLP分子标记技术,对9份常用狗牙根材料的遗传多样性进行了分析.结果表明:13对引物共扩增出1326个条带,平均每对引物扩增出93.2条带,其中多态性条带有1212条,多态性条带比率为91.71％,材料间遗传相似系数(GS)为0.469～0.797,变幅为0.328.聚类分析表明,在GS值为0.648处,可将9份常用狗牙根材料分为5类:T-419、小矮人和老鹰草为一类,摄政王单独为一类,瑞拉和黑杰克为一类,南京狗牙根和普通狗牙根     

外源NO对NaCl胁迫下燕麦幼苗氧化损伤的缓解效应

以加燕2号为试验材料,用一氧化氮（NO）供体硝普钠（SNP）、NO清除剂牛血红蛋白（Hb）及SNP类似物亚铁氰化钠处理燕麦植株,研究NO对NaCl胁迫下燕麦幼苗生长和氧化损伤的缓解效应。结果表明,NaCl胁迫下添加外源NO提高了燕麦幼苗的株高,提高了SOD、POD、CAT和APX活性,降低自由基含量和膜脂过氧化程度,表明外源NO能缓解NaCl胁迫诱导的氧化损伤,增强植株的耐盐性。NO供体SNP的类似物亚铁氰化钠（不产生NO）对NaCl胁迫燕麦植株的株高和氧化伤害无缓解效应;施用Hb提高了自由基含量,降低了抗氧化酶活性,而添加外源NO能缓解Hb对燕麦生长的抑制,表明内源NO也可能参与燕麦幼苗耐盐性的调节。     

石羊河国家湿地公园乔木群落及林下植被多样性分析

研究了石羊河国家湿地公园乔木群落及其林下植被组成特征和物种多样性,为该区域的植被管理提供理论依据。采用分层样方抽样法调查石羊河国家湿地公园的乔木群落及林下植被,分析湿地公园植被组成特征和物种多样性。结果表明：共调查到21科、38属、51种植物,其中乔木层共4科、6属、13种,灌木层共5科、8属、9种,草本层共14科、24属、29种;以乔木层优势树种对调查林分进行划分和命名,可分为7个植被群系,分别为旱柳群系、线叶柳群系、沙枣群系、小叶杨群系、二白杨群系、新疆杨群系和胡杨群系,每个群系中植被组成存在一定的差异;7个植被群系乔木层和灌木层的Simpson指数和Shannon-Weiner指数整体小于草本层,但乔木层的Pielou均匀度指数整体大于灌木层和草本层。综上,石羊河国家湿地公园乔木群落及林下植被林分结构比较简单,树种单一,物种多样性较小,林分稳定性较差。     

家蚕第2隐性赤蚁的遗传学研究——Ⅱ.ch-2基因的连锁分析

Ch-2基因是继ch之后新发现的一种隐性赤蚁ch-2基因与pM(2)、Ze(3)、L(4)、Pe(5)、E~(EL)(6)、q(7)、st(8)、I(9)、w-2(10)、ms(12)、cf(13)、U(14)、Se(15)、cts(16)、B_m(17)、nb(19)、rb(21)、or(22)、sp(23)、Nd(25)、及Y_m等各标志基因都是独立遗传.Ch-2与mln杂交F_2代分离+ch-2+min:ch-2+min:ch-2mln:ch-2mln=523:284:231:0≈2:1:1:0;ch-2与elp杂交F_2代分离+ch-2+elf:ch-2+elp:+ch-2elp:ch-2elp=219:97:68:0≈2:1:1:0,充分说明ch-2与mln、elp是连锁遗传的,即ch-2基因位于第18连锁群.     

QuEChERS法在兽药残留检测中的优化与应用

兽药的不合理使用可导致动物产品及环境中兽药残留超标,从而对公共卫生安全构成威胁。QuEChERS法是一类快速、简便、经济、高效、耐用和安全的样品前处理方法,常用于植物产品农药检测。通过持续优化,目前该方法开始在动物产品兽药残留检测中得到应用。本文综述了QuEChERS法的特点,探讨了该方法在畜禽产品或样品兽药残留检测中的优化与应用。与植物样品相比,动物相关样品基质复杂,脂肪含量较高,因此需要对QuEChERS法进行优化。常用的优化方式包括提取液优化、脱水盐优化和吸附剂优化。目前QuEChERS法在畜禽肌肉、内脏、鸡蛋、牛奶及相关产品以及尿液、粪便等环境样品兽药残留萃取中得到应用。随着与其他提取净化方法的连用以及自动化提取装置的不断更新,未来QuEChERS法会得到持续优化与发展,其提取效率和净化效果将进一步得到提高,并将在动物产品残留检测中发挥重要作用。     

Role of IFNLR1 gene in PRRSV infection of PAM cells

BackgroundInterferon lambda receptor 1 (IFNLR1) is a type II cytokine receptor that clings to interleukins IL-28A, IL29B, and IL-29 referred to as type III IFNs (IFN-λs). IFN-λs act through the JAK-STAT signaling pathway to exert antiviral effects related to preventing and curing an infection. Although the immune function of IFN-λs in virus invasion has been described, the molecular mechanism of IFNLR1 in that process is unclear.ObjectivesThe purpose of this study was to elucidate the role of IFNLR1 in the pathogenesis and treatment of porcine reproductive and respiratory syndrome virus (PRRSV).MethodsThe effects of IFNLR1 on the proliferation of porcine alveolar macrophages (PAMs) during PRRSV infection were investigated using interference and overexpression methods.ResultsIn this study, the expressions of the IFNLR1 gene in the liver, large intestine, small intestine, kidney, and lung tissues of Dapulian pigs were significantly higher than those in Landrace pigs. It was determined that porcine IFNLR1 overexpression suppresses PRRSV replication. The qRT-PCR results revealed that overexpression of IFNLR1 upregulated antiviral and IFN-stimulated genes. IFNLR1 overexpression inhibits the proliferation of PAMs and upregulation of p-STAT1. By contrast, knockdown of IFNLR1 expression promotes PAMs proliferation. The G0/G1 phase proportion in IFNLR1-overexpressing cells increased, and the opposite change was observed in IFNLR1-underexpressing cells. After inhibition of the JAK/STAT signaling pathway, the G2/M phase proportion in the IFNLR1-overexpressing cells showed a significant increasing trend. In conclusion, overexpression of IFNLR1 induces activation of the JAK/STAT pathway, thereby inhibiting the proliferation of PAMs infected with PRRSV.ConclusionExpression of the IFNLR1 gene has an important regulatory role in PRRSV-infected PAMs, indicating it has potential as a molecular target in developing a new strategy for the treatment of PRRSV.     

Graft-versus-host reaction (GVHR) in clonal amago salmon,Oncorhynchus rhodurus

The graft-versus-host reaction (GVHR) was demonstrated in a salmonid model system of clonal diploid and triploid amago salmon. Triploid operculum grafts on clonal diploid evoked an acute rejection within 12 days. Grafts exchanged among triploid amago salmon exhibited prolonged survival for 18 days. In contrast, diploid grafts on triploid, and allografts among clonal diploid amago salmon were accepted. A typical GVHR was induced in triploid recipients by intraperitonal injection of head kidney cells from sensitised diploid donors. The clinical signs of graft-versus-host disease (GVHD) were observed in the recipients after 1 week of cell injection as a loss of appetite and appearance of solid faeces, followed by haemorrhage, local swelling of ventral skin and an enlarged spleen. Three of six fish died within 1 month. Water temperature and frequency of sensitisation are critical to induce GVHR. Diploid donors had to be sensitised three times at 20 degrees C to induce the typical GVHR. GVHR was most effectively induced by head kidney cells, followed by peripheral blood leucocytes (PBL) and spleen cells. Ploidy analysis by flow cytometry revealed that the donor head kidney cells greatly increased in the recipient liver, head kidney and spleen, and reached the peak after 9 days of donor cell injection. The results in the present study are quite similar to the findings in ginbuna and ginbuna-gold fish hybrid system, suggesting the presence of T cells in salmonid as well as cyprinid fish.