IBD-based QTL detection in inbred pedigrees: A case study of cereal breeding programs

Mapping quantitative trait loci in plants is usually conducted using a population derived from a cross between two lines. The power of such QTL detection and mapping strategies and the estimation of the effects highly depend on the choice of the two parental lines. Thus, the QTL detected in such populations only represent a small part of the genetic architecture of the trait. Besides, the effects of only two alleles are characterized, which is of limited interest to the breeder. On the other hand, common pedigree breeding material remains unexploited for QTL mapping. From a pre-breeding perspective, the utilization of the good quality phenotypic data generated by breeders can be improved through the search and manipulation of QTL. The development of statistical techniques suitable for QTL mapping in general conventional breeding populations is thus challenging. In this study, we extend QTL mapping methodology to a generalized framework, based on a two-step IBD variance component approach, applicable to any type of breeding population coming from inbred parents. The proposed developments attempt to make full use of any inferable relatedness information between the parents. The power and accuracy of this method were assessed on simulated data mimicking conventional breeding programs in cereals, in an effort to reproduce actual conditions of marker and gene allelic frequencies across the parental lines. A wide range of breeding scenarios and of genetic architectures was explored. We demonstrated that taking into account the estimable relatedness between the parents significantly improved the power and accuracy of the QTL parameter estimations. This revised version was published online in July 2006 with corrections to the Cover Date.     

紫锥菊、黄芪对法氏囊病雏鸡的肝损伤及脾脏NK细胞活性的影响

给14日龄雏鸡灌服不同浓度紫锥菊、黄芪合剂,连续灌服7d,21日龄时雏鸡接种传染性法氏囊病病毒(IB-DV),来观察雏鸡血液转氨酶活性及脾脏NK细胞活性的变化。结果显示,攻毒后4d和攻毒后11d时用药组与攻毒对照组相比,谷草转氨酶(Ast)、谷丙转氨酶(Alt)均有所降低,差异显著(P<0.05);攻毒后11d时Ast/Alt比值极显著低于攻毒对照组(P<0.01)。脾脏NK细胞活性在感染后14d,高剂量组活性极显著高于攻毒对照组和空白对照组(P<0.01),感染21d后各组差异不显著。结果表明,紫锥菊、黄芪合剂在雏鸡感染IBDV后12d前后一段时间可显著降低传染性法氏囊病病毒对肝脏造成的损伤,促进脾脏NK细胞的活性,增强机体的防御功能,有利于该疾病的防治。     

蒙成药巴日布·寸汤对鸡新城疫及鸡传染性法氏囊病免疫增强的研究

本试验以鸡新城疫 (ND)和鸡传染性法氏囊病 (IBD)为模型研究蒙成药巴日布·寸汤对ND弱毒苗和IBD中毒苗免疫效果的影响。采用HI微量血凝抑制试验和间接ELISA分别测定抗体效价 ,结果表明 ,巴日布·寸汤与ND及IBD疫苗同期配合使用 ,具有增强机体免疫作用 ,可明显地提高机体的体液免疫水平。     

鸡传染性法氏囊病流行毒株的分离与鉴定

对洛阳、焦作、平顶山、南阳四地区鸡传染性法氏囊病的发病鸡群进行了病原分离，经AGP和Dot－ELISA法检测、鸡体回归试验、鸡胚传代及理化特性的测定，证明为IBD强毒，其中南阳株毒力稍弱于其它3株。四种野毒株的毒价分别为10-7．88、10-7．5、10-6．56和10-5．6ELD50／0．2ml。     

中草药方剂对鸡传染性法氏囊病的治疗及免疫试验

按中兽医学理论,针对鸡传染性法氏囊病研制成中草药方剂进行治疗和免疫试验。结果表明,该方剂对鸡传染性法氏囊病有很好的治疗作用,治愈率在89%以上;并能促进小白鼠淋巴细胞玫瑰花结形成,增强机体免疫功能。     

“营养液1号”对雏鸡ND及IBD免疫的影响

将一日龄蛋用雏鸡160只随机分为实验组和对照组，给实验组雏鸡在1－14日龄饮用1．5％“营养液1号”，每日10h。在ND和IBD一免和二免后监测各组鸡的ND和IBD的抗体效价。结果表明：“营养液1号”可增强雏鸡ND和IBD疫苗的免疫效果，实验组的抗体效价明显高于对照组（P＜0．05），并且持续时间长。     

几种主要禽疫病诊断基因芯片的制备及初步应用

进行了几种主要禽疫病诊断基因芯片制备及其初步应用研究。试验分别设计和克隆鉴定了NDV、IBV、AIV和IBDV的靶基因重组质粒。以克隆的靶基因重组质粒为模板。分别进行PCR扩增制备靶基因并纯化，以基因芯片点样仪将制备的靶基因点制在氨基化的基片上，经干燥、水合、紫外线交联和洗涤后，成功制备了NDV-IBV-AIV-IBDV诊断基因芯片。试验应用CY3荧光标记制备的探针进行芯片的检验，结果表明制备的NDV-IBV-AIV-IBDV诊断基因芯片质量好，可对NDV、IBV、AIV和IBDV进行诊断检测，具有检测灵敏性好，特异性高和芯片可重复检测的优点。试验对30个临床样品进行初步应用检测，结果表明该诊断基因芯片技术与RT—PCR检测技术检出率基本一致，并具有同步诊断检测多种疫病的优点。     

酵母诱导表达鸡IFN-α抗IBDV效果及其对信号分子PI3K和NF-κB的影响

试验旨在研究酵母表达鸡IFN-α抗传染性法氏囊病病毒（IBDV）的效果及对其淋巴细胞信号分子PI3K和NF-κB p65的影响。将40只10日龄非免疫雏鸡随机分为IFN-α组和空白对照组,持续注射给药3 d后,于第3次给药后第1天开始每天心脏采血,持续3 d,并于最后一次采血后对雏鸡进行攻毒,在攻毒后开始每天心脏采血,连续3 d。通过MTT法检测淋巴增殖活性情况,ELISA测定不同时间段淋巴细胞中PI3K的水平、细胞中总NF-κB p65、细胞核中NF-κB p65蛋白表达含量及IBDV抗原量。结果显示,与对照组相比,攻毒前,IFN-α对淋巴增殖活性、细胞中PI3K和NF-κB p65的表达具有极显著地促进作用（P<0.01）;与攻毒前相比,攻毒后第1和2天IFN-α组淋巴增殖活性、细胞中PI3K和NF-κB p65的表达极显著增加（P<0.01）,IFN-α对IBDV-Ag具有极显著地抑制效果（P<0.01）。这些结果表明,IFN-α可通过增加PI3K激活NF-κB信号通路以增强机体免疫反应,并对IBDV-Ag有显著的抑制作用,本试验为IFN-α免疫增强和抗病毒作用的研究提供科学依据。     

Antimicrobial Resistance Impacts Clinical Outcome of Granulomatous Colitis in Boxer Dogs

Background: Escherichia coli have recently been identified within the colonic mucosa of Boxer dogs with granulomatous colitis (GC). Eradication of invasive E. coli is associated with clinical and histological remission. Objectives: To determine antimicrobial susceptibility profiles of E. coli strains from GC and healthy dogs, and the association of antimicrobial resistance with clinical outcome. Animals: Fourteen Boxer dogs with GC and 17 healthy pet dogs. Methods: Prospective study: E. coli was cultured from GC biopsies and rectal mucosal swabs of healthy dogs. Individual strains were selected by phylogroup and overall genotype, determined by triplex‐ and random amplified polymorphic DNA‐polymerase chain reaction respectively. Antimicrobial susceptibility was determined by broth microdilution minimal inhibitory concentration. Results: Culture yielded 23 E. coli strains from GC (1–3/dog, median 2) and 34 strains from healthy (1–3/dog, median 2). E. coli phylogroups were similar (P= .18) in GC (5A, 7B1, 5B2, 6D) and healthy (2A, 10B1, 15B2, 7D). Resistance to ampicillin, amoxicillin‐clavulanate, cefoxitin, tetracycline, trimethoprim‐sulfa (TMS), ciprofloxacin, and chloramphenicol was greater (P < .05) in GC (21–64%) than healthy (0–24%). Enrofloxacin resistant E. coli were isolated from 6/14 GC versus 0/17 healthy (P= .004). Of the enrofloxacin resistant cases, 4/6 were also resistant to macrophage‐penetrating antimicrobials such as chloramphenicol, rifampicin, and TMS. Enrofloxacin treatment before definitive diagnosis was associated with antimicrobial resistance (P < .01) and poor clinical outcome (P < .01). Conclusions and Clinical Importance: Antimicrobial resistance is common among GC‐associated E. coli and impacts clinical response. Antimicrobial therapy should be guided by mucosal culture and antimicrobial susceptibility testing rather than empirical wisdom.     

"禽福、亿妙灵"对雏鸡IBD疫苗接种后免疫细胞数量的影响

分别应用免疫组织化学和组织化学方法对使用免疫增强剂“禽福”和“亿妙灵”的1日龄SPF雏鸡接种IBD疫苗后,对其免疫器官胸腺、法氏囊、脾脏的T细胞和IgG、IgM、IgA抗体生成细胞数量的动态变化进行了较全面系统的研究。结果表明,不论是使用“禽福”,还是“亿妙灵”的雏鸡,接种IBD疫苗后,其上述各项被检指标均不同程度地高于IBD疫苗单独接种雏鸡。其中,“禽福”IBD疫苗接种雏鸡又较“亿妙灵”IBD疫苗接种雏鸡明显增加。表明免疫增强剂“禽福、亿妙灵”能明显提高雏鸡对IBD疫苗的免疫应答,增强IBD疫苗接种雏鸡对vvIBDV攻击的免疫保护率。