Meta分析是一类可以将多项研究结果整合在一起加以分析的统计方法.该方法通过收集与主题相关的研究结果,并将每个研究结果计算为一个统一的指标(效果量),然后对不同研究的效果进行量化加以统计分析.文章综述了Meta分析方法的发展历史、Meta分析方法的一般性步骤、常用统计模型以及该方法在动物遗传育种研究中的候选基因研究、QTL定位和全基因组关联分析这三个方面的应用.

随着现代分子生物学技术的飞速发展和进步,分子标记新技术应运而生.国内传统育种研究重点在地方品种、培育品种的种质评定等方面.生长、胴体、毛皮等性状的研究成为了分子遗传育种研究的重点.本文主要对家兔的毛皮、生长、繁殖、抗病等性状遗传多样性的候选基因进行了综述.

为研究过氧化氢酶对断奶仔猪生长性能的影响,试验采用将128头28日龄的健康杜长大断奶仔猪按体重相近(约7kg)、公母各占1/2的原则随机分为4个处理组,每个处理组4个重复,每个重复8头猪.对照组饲喂基础日粮,试验1、2、3组分别在基础日粮中添加0.05％、0.1％、0.15％过氧化氢酶.结果表明,试验组的平均日增重均高于对照组,其中试验2、3组差异显著(p＜0.05),日增重提高了9.26％、7.41％.料肉比和腹泻率降低,差异显著(p＜0.05).

本文通过在日粮中添加过氧化氢酶,来探讨过氧化氢酶对怀孕母猪繁殖性能的影响,为猪的生产实践提供理论参考依据.本次试验将72头怀孕长大母猪随机分为两组,形成典型对照试验,分别喂给过氧化氢酶制剂添加料和常规料,然后收集怀孕35天活胚数、活胚重、产仔数、健仔数、初生均重等数据.结果表明过氧化氢酶能防治母猪群外源性繁殖力低下综合征,通过促进精氨酸内源合成,提高动物窝产仔数和初生重,增强种母猪的繁殖力,清除母猪群毒素干扰状态,持续保持母猪群高PSY水平,解除母猪氧化应激状态,保持后续高水平的MSY,增值原有效益.

本研究采用单因子设计,选用(75.0±2.5)kg健康PIC生长猪30头,随机分成A组(湿发酵豆粕)、B组(发酵豆粕)和C组(基础饲粮)3个处理中,每个处理6个重复,每个重复1头猪.以玉米-豆粕型饲粮为基础饲粮,A组复合蛋白质(10.0%)和B组复合蛋白质(10.0%)分别替代基础饲粮中粗蛋白质含量的30%构成A组和B组试验饲粮.试验期30天,试验期间记录每组实验猪的采食量,试验结束后对所有实验猪进行称重,每个处理随机选3头猪屠宰,收集胃内容物测定胃的pH,截取1cm左右的十二指肠考察用于病理分析肠绒毛的长度,隐窝的深度.结果表明:平均日增重(ADG:Average Daily Gain)上A、B组与C组差异显著(P<0.01),同时,A、B组差异显著(P<0.05).日均采食量(ADFI:Average Daily Feed Intake)上A组比B组多160g,比C组多420g.料肉比(G/F:Gain/Feed)表明,A组最低,C组最高.A组胃内食糜pH显著低C组(P<0.01)和B组(P<0.05),B组与C组之间pH的差异也很显著(P<0.05).病理结果显示,A组、B组绒毛高度均明显优于C组(P<0.01).隐窝深度均显著低于C组(P<0.01).A组、B组绒毛高度/隐窝深度值均显著高于C组(P<0.01).

育种是培育和改进优良动物的有效手段,提高畜产品品质的基础.通过育种工作可以提高畜群的生产性能,使其充分利用杂种优势,达到工业化畜牧业,降低能耗,提高生产效率和经济效益.文章通过不同育种方法阐述有关于羊的育种技术进展.

Tail analysis and genome-wide association studies(GWAS) were combined in this study to determine preliminary two tails selection criterions.A total of 2 000,1 500,1 000 and 500 samples and 20％,15％,12％,10％,8％,5％ of two tails were used to run GWAS to estimate the effects of the population size on GWAS and the effect of the proportion of two tails on GWAS,respectively.The results showed that the number of significant SNPs decreased with the reducing population size and the proportion of two tails.The preliminary selection criterions were:traits with heritability of about 0.38,the proportion of two tails of 8％,10％,10％ and 20％ from 2 000,1 500,1 000 and 500 samples,which were appropriate for two tails population for running GWAS,respectively.Further,the traits with heritability of about 0.50,the proportion of two tails of 5 ％,5％,10％ and 15％ from 2 000,1 500,1 000 and 500 samples were appropriate for two tails population for running GWAS,respectively.The present preliminary two tails selection criterions from populations with various sizes to run GWAS could detect significant SNPs effectively and also provide a strategy of reducing the cost of GWAS.

随着科学的进步,基因编辑技术得到不断发展,从同源重组与第一代人工核酸内切酶(ZFN)到第二代内切酶转录激活因子样效应蛋白核酸酶(TALEN),再到如今出现的CRISPR/Cas9技术,基因编辑工具得到进一步的发展,降低了成本,简化了操作步骤,提高了作用效率.该文简述了基因编辑技术的发展进程以及最新编辑技术CRISPR/Cas9的应用情况、问题和前景.

选21日龄断奶的健康、体重相近杜长大仔猪81头,按试验要求完全随机分成3组,每组3个重复栏,每栏重复9头.结果表明:碱铜、碱锌作为一种新型铜源和锌源,在促生长、提高饲料转化率、抗腹泻的作用方面比硫酸铜和氧化锌有明显的优势.

全基因组选择(Genomic selection，GS)，即全基因组范围内的标记辅助选择(marker-assisted selection， MAS)。因其具有可缩短世代间隔，提高年遗传进展；早期选择准确率高；同时还能提高低遗传力、难以测量性状选择效率等诸多优点，目前已成为动物遗传育种领域的研究热点。文内围绕“什么是GS”“、为什么选用GS”以及“影响GS的因素”这3个方面全方位诠释了GS。重点阐述了GS在猪育种中的应用现状，并结合GS在奶牛上的成功应用，简述了GS在猪育种上的展望。

随着生活品质的改善，人们对肉质的要求不断的提高，猪肉脂肪沉积逐渐成为研究的热点。就类胰岛素样生长因子2（IGF-2）和心脏型脂肪酸结合蛋白（H-FABP）基因与猪脂肪沉积相关方面做一简要综述，以期为今后研究脂肪沉积提供一个参考。

The study was to investigate the regulation mechanism of miR-21 in skeletal muscle development.Using computational target prediction programs,we identified TSC1 and PPP3CA genes as the potential targets of miR-21 which can specify bind to their 3′ UTR regions.The 3′UTR regions of these two genes were amplified by PCR from Tongcheng pigs genomic DNA.The PCR productions were digested by double digestion with Not I and Xho I.We got the pCHE-TSC1-3′UTR and pCHE-PPP3CA-3′UTR vectors after digested products were ligated into the vector psiCHECK with the dual-luciferase gene.These vectors were transfected into porcine iliac endothelial cell line(PIEC) and porcine kidney epithelial cell line(PK15),and then the luciferase activity was tested by a dual-luciferase reporter assay.The results showed that the luciferase activity of experimental group was significantly lower than that of the control(P0.05)both in PIEC and PK15.This study demonstrated that TSC1 and PPP3CA were the possible target genes of miR-21 and provides basic for further research the function of miR-21.

试验以大白猪为研究对象,采用PCR-SSCP方法对DECR1基因exon5(外显子5)的多态性位点进行了遗传结构的分析,并对这个多态性位点与胴体性状的关联性进行了研究,结果表明,DECR1基因在该位点上,由C、G 2个等位基因产生了CC、CG和GG 3种基因型,CG基因型为优势基因型,在该位点存在较大遗传变异。GG基因型脂肪率与CC基因型脂肪率存在显著差异(P<0.05)。

试验以9个猪品种/品系(5个地方品种:宁乡猪、大围子猪、沙子岭猪、桃源猪、五指山猪;3个外来品种:大白猪、长白猪、杜洛克猪;1个杜长大杂交品系)共计687头猪为研究对象,通过PCR-RFLP方法分析了CCKAR基因+179A/GHpy8I酶切位点和+471C/GSatI酶切位点的基因频率和基因型频率,并进行了Hardy-Weinberg平衡检验。在所有猪种群体中,CCKAR基因+179A/GHpy8I酶切位点和+471C/GSatI酶切位点均存在较丰富的遗传多态性。在+179A/GHpy8I酶切位点中除宁乡猪中没检测到AA基因型个体外,其他品种中都检测到AA、AG、GG3种基因型个体的分布;而CCKAR基因+471C/GSatI酶切位点都检测到了CC、CG、GG基因型个体的分布。

The three Chinese indigenous goat breeds,Anhui white goat(Anbai),Xiangdong black goat(Xiangdong) and Matou,and two imported goat breeds,Boer and Sanen,were selected.The polymorphisms in the 5' regulatory region and exon 13 of PRKAG3 gene were detected using PCR-RFLP and estimated via heterozy-gosity and polymorphism information content(PIC).The results showed that four polymorphic loci,C-525A and C-225T in the 5' regulatory region and T90C and C102T in the exon 13,were found in five goat breeds.The C-525A,C-225T and C102T were low-grade polymorphic loci,but the T90C was moderate polymorphic locus(0.25PIC0.50).Of which the heterozygosity in Boer was 0.3750 while that in Xiangdong was 0.2366.The linkage analysis results showed that the average heterozygosities of Anbai(0.2208) and Boer(0.2085) were higher than that of other goat breeds,while that of Matou,Xiangdong and Sanen were from 0.12 to 0.14.From the gene diversity,5 goat breeds may be divided into three types: Sanen,Boer and Chinese indigenous goat breeds.

Adenosine Monophosphate activated Protein Kinase (AMPK) plays a key role in cellular metabolism and regulating energy and its gamma 3 subunit was encoded by the PRKAG3 gene which was regarded as the candidate gene for carcass quality trait in domestic animals and fowls. To understand PRKAG3 gene variation and its association with carcass quality of goat breeds, the polymorphism of goat PRKAG3 gene and its distribution patterns in different goat breeds were investigated. Five goat breeds selected were Anhui white goat, Matou, Boer, Xiangdong and Sanen dairy goat. DNA samples of all goat breeds were extracted from goat ear tissue. The polymorphisms in the 5' regulatory region and exon 13 of PRKAG3 gene were examined using ApaI, Hpy188I, AciI and ClaI enzyme digestion, respectively and their distribution patterns were analyzed in different goat breeds. The results showed that two mutation loci in the 5' regulatory region, C-525A and C-225T, located at -525 and -225 bp upstream of the start codon of the PRKAG3 gene and two mutation loci in the exon 13, T90C and C102T, located at 90 bp and 102 bp of the exon 13. The 525CC genotype frequencies of five goat breeds listed above were 0.8000, 0.9681, 0.6042, 0.7557 and 0.8889, respectively, while 225CC genotype frequencies corresponding to 0.7391, 0.9750, 0.8684, 0.9785 and 0.9344. The mutations at T90C and C102T didn't cause the substitution of corresponding amino acids in the AMPK protein. The muscle fat grade and carcass fat grade are lower in goat breeds with higher 525CC225CC genotype frequency while higher in the breeds with higher 525CA225CT genotype frequency (p<0.05). The results suggest that the lipoidosis ability of goat breeds may be associated with C-525A and C-225T loci of PRKAG3 gene.

试验选取24头28日龄、体重8.4千克左右的杜长大三元杂交仔猪,随机分成2组,每组2个重复,每个重复6头猪。分别饲喂玉米-豆粕型基础饲粮和在此基础上添加0.2%复合酸化剂的饲粮。结果表明:添加酸化剂能提高仔猪日增重9.2%(P<0.05),降低料肉比8.7%,降低腹泻率42%(P<0.05)。