Polymorphism of Exon 2 of FSHβ Gene and Its Relationship with Reproduction Performance in Two Goat Breeds

The objectives of the present study were to detect the polymorphism in follicle stimulating hormone beta （FSHβ） gene and investigate the relationship between FSHβ gene and high prolificacy in goats.According to the sequence of ovine FSHβ gene,two pairs of primers were designed to detect single nucleotide polymorphism of exon 2 of FSHβ gene in two goat breeds,Xinong Saanen dairy goat and Boer goat,by PCR-SSCP.The least square mean and genetic variance of different genotypes at polymorphic locus were analyzed,and the selection reaction was forecasted by genetic correlation between marker locus and genetic variance of litter size traits.There was one polymorphic locus occurring in exon 2 （P2） with three genotypes （EE,EF and FF）.In Xinong Saanen dairy goat,EE genotype had significantly higher （P 〈 0.05） litter size than EF and FF genotype in the first to fourth parity and average parity;EF genotype had significantly higher （P 〈 0.05） litter size than FF genotype in the second and average parity.In Boer goat,EE genotype had significantly higher （P 〈 0.01） litter size than EF and FF genotype in the second to fourth parity and average parity;EF genotype had significantly higher （P 〈 0.05） litter size than FF genotype in average parity.In Xinong Saanen dairy and Boer goat,the heredity of litter size was mainly influenced by genetic additive effect and the EE genotype is a favorable marker genotype for litter size in these two breeds.     

Correlation Analysis on Single Nucleotide Polymorphism of CAPN1 Gene and Meat Quality and Carcass Traits in Chickens

The selection of meat quality has received considerable focus in chicken breeding. This study was aimed at investigating the effect of CAPN1 gene on meat quality traits in chicken populations. Primer pairs for 3 UTR in CAPN1 were designed from database of chicken genomic sequence. Polymorphisms were detected using PCR-SSCP and DNA sequencing. A mutation at position 9 950 nt （G/A, locus A） was found among individuals in each population. The allele and genotype frequencies significantly differed among eight lines with higher frequencies of allele A2 and genotype AIA2 （P〈0.01）. The least square analysis showed that there was significant difference （P 〈 0.05） in muscle fiber density and some carcass traits among genotypes and that the breast muscle fiber density （BFD） of birds ofAIA1 genotype was significantly higher （P〈0.05） than that of birds ofA2A2 genotype. It was concluded that the CAPN1 gene was the major gene affecting the muscle fiber traits of chicken or was linked with the major gene. These results were useful for studying the molecular mechanism that influences meat traits and were used as the base of molecular-assisted selection to meat quality traits. So, this site may be a potential marker affecting the muscle traits of chickens.     

Investigation of Genetic Variation of B-G Gene with PCR-SSCP and RFLP in Chinese Indigenous Chickens

To reveal genetic variation of MHC B-G gene at Chinese native chickens, two PCR primer pairs were designed to hybridize specifically with conserved sequences surrounding hypervariable regions within the B-G gene and used to amplify two DNA fragments in ten Chinese indigenous chicken breeds and one introduced breed. The fragments were cloned and sequenced to assure that the expected sequences of chicken B-G gene were isolated. Of which the 189 bp fragment encompassing the most variable region within exon 2 of B-G gene was employed for PCR-SSCP assay, this method provided evidence for the presence of at least 56 B-G genotypes in the Chinese chickens sampled. It revealed a high degree of diversity in B-G genes of Chinese local breeds; particularly, high variation of B-G gene was confirmed with the presence of 48 B-G genotypes within Tibetan chicken population. Not only can the B-G genotypes be used to preliminarily screen new B-G alleles, but also they would be utilized to investigate MHC haplotypes and matched unrelated donors for bone marrow transplantation in immune researches. Another fragment of 401 bp size spanning over partial intron 1 and exon 2 of B-G gene was employed for PCR-RFLP analysis with two restriction enzymes of Msp Ⅰ and Tas Ⅰ in the breeds sampled. In this part of the gene, three novel SNPs were detected at the two restriction sites. It was more generally found the transition of two nucleotides of A294G and T295C occurred at Tas Ⅰ restriction site, and consequently led to a non-synonymous substitution of asparagine into serine at position 54 within the deduced amino acid sequence of immunoglobulin variable-region-like domain encoded by the exon 2 of B-G gene. It was observed at rare frequency that an alone mutation of A294G occurring at the site, which also caused the substitution of amino acid, asparagine 54-to-serine;and we haven't found only single mutation occurred at position 295 of the restriction site. At the Msp Ⅰ site, the transversion of G318C led to a non-synonymous substitution, glutamine 62-to-histidine. The variations at expression level caused by the genetic variability of B-G gene may bring about the changes in immune specificity of B-G antigen finally. Furthermore, two alleles, A and B, were identified at Msp Ⅰ and Tas Ⅰ loci of B-G gene, respectively. The allele frequencies were estimated, which gave a nonsymmetrical distribution either in the eight Chinese local breeds or in the introduced breed. By comparison, allele A at Msp Ⅰ locus was tended to be dominative, while, the allele B at Tas Ⅰlocus was tended to be prevalent in the breeds analyzed. It is concluded that the genetic variability of B-G gene revealed by the PCR-SSCP and RFLP assays in Chinese native chickens provide molecular data for further investigating the varied immune functions of B-G antigen; and the PCR-RFLPs at Msp Ⅰ and Tas Ⅰ loci of B-G gene might be used as genetic markers in selecting for the traits of disease resistance in chicken breeding.     

Analysis of PRLR and BF Genotypes Associated with Litter Size in Beijing Black Pig Population

This study is aimed at using the DNA mutations in the prolactin receptor （PRLR） and properdin （BF） genes to determine associations between the genotype and litter size in the Beijing Black pig population. A total of 321 Beijing Black pig sows were genotyped using the polymerase chain reaction-restriction fragment length polymorphism （PCR-RFLP） method, with the Alu I and Sma I for PRLR and BF genes, respectively. Two different alleles of PRLR and BF genes were identified： allele A （0.25） and B （0.75） of the PRLR gene, allele A （0.13） and B （0.86） of the BF gene. The association analysis between the genotypes and the litter size were estimated with the method of the general linear model. The analysis results of PRLR showed that in first parity, sows with genotype AA had a larger litter size than sows with genotype AB and BB, but the difference was statistically not significant. In later parities, statistically significant （P 〈 0.05） differences were seen between sows with genotypes AA and AB, and BB of the PRLR gene. The associated analysis results between genotypes and litter size （total number born, TNB, and number born alive, NBA） showed that there were no significant differences in the first parity sows with different genotypes of the BF gene, but significant differences appeared in NBA between the sows of genotypes AB and BB, in later parity, for which significantly higher values were observed in the offspring of heterozygotes. Considering the consistent genotypic effect on the litter size of both sows in first parity and later parity, it was concluded that the locus of the PRLR gene, digested with Alu I, could be the gene maker for the litter size in Beijing Black pigs.     

Sequencing, Polymorphism and Expression Profile Analysis of Porcine Hexokinase Ⅱ （HK2） Gene

Hexokinase Ⅱ has been demonstrated to play the role of a key enzyme member in the glycolysis reaction. It catalyzes the conversion of glucose to glucose-6-phosphate, thus committing glucose to the glycolytic pathway. In this paper, the partial exons and introns 10, 11, 13 and 14 of the porcine HK2 gene were cloned and sequenced by comparative genomics. Comparative sequencing of three pig breeds revealed ten putative single-nucleotide polymorphisms （SNPs）, one of which in intron 10 with differing bases （G981A） is within the restriction site for enzyme Msp I. Distribution of Msp I -RFLP genotype and allele frequencies among different pig breeds were studied. By association analysis between Msp I PCR- RFLP polymorphism （AA, AB, BB genotypes of HK2 gene intron 10） and some meat quality and carcass traits in F2 group, which was constructed by our laboratory, a significant difference of pig average backfat at rump was found between AB and BB genotypes （P〈0 05） in F2 group. In addition, the pattern of expression of ilK2 in a variety of tissues in pig was also determined using semi-quantitative RT-PCR. The expression of HK2 mRNA was detected only in pig skeletal muscle.     

Dietary Methionine Affect Meat Qulity and Myostatin Gene Exon 1 Region Methylation in Skeletal Muscle Tissues of Broilers

Dietary amino acids imbalance will result in stunted broiler performance and deteriorated meat quality, which are involved in various biochemical cycles in vivo. In this study, the effects of dietary methionine on meat quality and methylation of myostatin exon 1 were investigated. Drip loss of the broilers fed with diet of high methionine levels （0.2%） increased from （6.3 ± 0.1）% （control group） to （10.1 ± 1.0）%, and the muscle shearing force increased from （22.8 ± 1.9） N （control group） to （26.3 ±2.3） N. Moreover, many CpG sites were found at the myostatin exon 1 region （nucleotides 2 360-2 540 bp）. To further understand the regulation of broiler myostatin expression, the methylation status of broiler myostatin exon 1 and its mRNA expression were analyzed. At the myostatin exon 1 region where CG enriches （nucleotides 2 360-2 540 bp）, the percentages of methylation were 46 and 84% in low Met and high Met content groups after 55-d feeding, respectively. In skeletal muscle tissues, the exon 1 hypermethylation status of myostatin gene was found to be negatively correlated with the gene expression. These results suggested that methylation of this gene is a dynamic process, which plays a dominant role in regulating gene expression for development of individuals.     

Corelation Between Single Nucleotide Polymorphisms in Mu Opioid Receptor Exon 2 and Stereotypic Behaviour in Sows

Three breeds of sows were observed to investigate the relationship between Single Nucleotide Polymorphisms（SNPs） in Mu Opioid Receptor（MOR）and stereotypic behaviour,such as,sham-chewing,bar biting and standing still in order to better understand the mechanism of stereotypic development of the animals in restrained conditions.MOR exon 2 partial sequences were amplified to analyze single nucleotide polymorphisms by PCR-SSCP.One SNP,a silence mutant was found.A significant difference （P〈0.01）was found in the frequency of genotypes in these 3 breeds where only the BB genotype,which was identical to that published in GenBank,was found in the Duroc breed,while no AA genotype was found in Landrace,3 genotypes AA,BB and AB were found in Yorkshire.The result also indicated that the individuals with AA and AB genotypes tended to be more active in sham-chewing than those with the BB genotype（P〈0.05）.The overall results of this study suggested that sham-chewing of sows may be subjected to both genetic control and environmental conditions,but activity level was more likely to be affected by their environment.We can putatively draw the conclusion that MOR gene has effect on the sham-chewing behavioral traits of sow.     

Identification of SNPs and Their Effects on Swine Growth and Carcass Traits for Porcine IGFBP-3 Gene

The insulin-like growth factor binding protein-3 （IGFBP-3） was known as a key factor that regulates the effect of insulin- like growth factors （IGF-1 and IGF-2） on pig growth and development. We first identified 38 single nucleotide polymorphisms （SNPs） from a fragment of the IGFBP-3 gene spanning 1 823 bp using the denaturing high-performance liquid chromatography （DHPLC） method and confirmed them by direct sequencing. Among these SNPs, 36 located in introns and the remaining 2 in the 3 prime untranslated region （3UTR）. In addition, 16 PCR-RFLP polymorphisms were identified within these SNPs. Three SNPs were then selected to genotype 272 F2 individuals with PCR-RFLP method and the association of polymorphism with growth and carcass traits were analyzed. The results showed that no significant associations were observed between polymorphisms of A265G and A952G and traits. However, the A2670G significantly related with live body length, loin muscle area, and skin and fat percentage （P〈0.05）; highly significantly associated with weight of carcass lean and lean percentage （P〈 0.01）.     

马IGF-Ⅰ基因3′端侧翼区PCR-SSCP多态性分析(英文)

[Objective] To explore the polymorphism of the 3′ flank region of equine IGF-Ⅰ gene. [Method] The 3′ flank region sequences of IGF-Ⅰ gene were amplified from genomic DNA of 270 horses, which included 4 types of Mongolian horse, Sanhe horse and Thoroughbred, and then analyzed by PCR-SSCP. [Result] Three genotypes (AA, BB and AB) were detected by PCR-SSCP and the distribution of genotypes of all research objects except Xinihe horse and Baerhu horse were in line with the "Hardy-Weinberg Law". [Conclusion] There was a polymorphic locus in the 3′ flank region of IGF-Ⅰ gene, which might affect the equine growth and development mechanism. The study is of important theoretical and practical significance to improve the performance and to develop equine industry.     

Sequence Variations in the Bovine IGF-I and IGFBP3 Genes and Their Association with Growth and Development Traits in Chinese Beef Cattle

The objective of this study was to determine the genotype effects of the bovine insulin-like growth factor I (IGF-I) and its binding protein 3 (IGFBP3) genes on growth and development traits in beef cows,including 130 Chinese Simmental,42 Nanyang,and 47 Luxi Yellow cattle.Sequence variations in the bovine IGF-I and IGFBP3 genes were investigated by single strand conformation polymorphism (SSCP).SSCPs were detected in 6 fragments,which is the 5'-flanking region,the 2nd exon,the 5th exon,and the 5th intron of the IGF-I gene,and the 2nd exon,the 3rd exon of the IGFBP3 gene.Two polymorphisms,an A-to-G transition in the 2nd exon of the IGF-I gene and a T-to-C transition in the 2nd exon of IGFBP3 gene were detected in 3 breeds.The allele frequencies of 2 polymorphisms were 0.0411 (A),0.9589 (B),and 0.7237 (A),0.2763 (B),respectively.These 2 loci were analyzed to associate with body weight,height at withers,body length,heart girth,rump width,and beef production index (BPI) at 0,6,12,24,and 36-month old.The 1GFBP3 locus was shown to be associated with rump width,heart girth at 24-month and 36-month.Animals with BB genotype had higher rump width (24.86±0.47) cm at 24-month and (27.50±0.63) cm at 36-month.The heart girth was highest for the individuals with BB genotype (171.33±1.84) cm and higher than those with AB genotype (166.68±1.13) cm (P＜0.05) at 36-month.     

两个贵州山羊品种GHSR和GHRL基因遗传变异及其与生长性状的关联性

【目的】探讨GHSR和GHRL基因作为山羊体重体尺性状候选基因的可能性,寻找与山羊生长性状相关的分子遗传标记。【方法】以贵州白山羊和贵州黑山羊为研究素材,采用DNA混合池结合PCR产物直接测序及PCR-SSCP技术检测GHSR和GHRL基因的单核苷酸多态性,利用SPSS (18.0)软件GLM统计模型分析基因SNPs不同基因型及合并基因型与贵州山羊生长性状的关联性,同时采用在线软件对GHSR基因进行生物信息学分析。【结果】在GHSR基因外显子2和3′UTR分别检测到G200A同义突变和T628C位点,而在5′UTR区和外显子1则未发现多态性。设计一对特异性引物对G200A位点进行PCR-SSCP分析,表现为3种基因型,依次命名为GG、GA和AA。GG基因型为优势基因型,在贵州白山羊和贵州黑山羊母羊群体中等位基因G为优势等位基因,其等位基因频率分别为0.6731和0.5243。而在贵州黑山羊公羊群体中A则为优势等位基因,其频率为0.5122。多态信息含量均表现为中度多态(0.25＜PIC＜0.50)。在GHRL基因内含子2处发现1个G141A突变,外显子2和外显子4处分别检测到2个同义突变(T78C和C14T),设计一对特异性引物对C14T位点进行SSCP分析,显示为2种基因型CT和CC。在所有试验群体中,CC基因型为优势基因型,其频率分别为0.7692、0.9417和0.9390,等位基因C为优势等位基因,其频率依次为0.8846、0.9709和0.9695,多态信息含量均显示为低度多态(PIC＜0.25)。χ²检验显示所有试验群体G200A和C14T位点基因型分布均符合Hardy-Weinberg平衡(P＞0.05)。关联分析表明,GHSR基因G200A位点与山羊体重、体高、体斜长和管围显著相关 (P＜0.05),纯合子GG基因型优势较为明显,贵州白山羊GG基因型个体的体高显著高于GA基因型个体和管围显著高于AA基因型个体(P＜0.05)。C14T位点贵州黑山羊 (公羊) CC基因型个体的体重、体高和胸围显著高于CT基因型 (P＜0.05)。组合基因型对体高和胸围指标的影响显著(P＜0.05),表现为CCGG合并基因型个体的体高显著高于CCAA合并基因型个体 (P＜0.05)。生物信息学分析揭露,GHSR基因5’UTR处未检测到核心启动子区和CpG岛,仅发现1个CAAT-box和部分潜在的转录因子结合位点,G200A导致mRNA二级结构发生明显变化。GHSR蛋白二级结构以α-螺旋为主 (48.90%),三级结构及跨膜螺旋结构预测表明该蛋白是膜蛋白。【结论】研究初步推测GHSR基因和GHRL基因多态性及合并基因型对山羊生长性状具有较显著的影响,G200A和C14T位点可作为山羊生长性状的有效遗传标记用于指导山羊的分子育种。     

Lpin1基因多态性与黄牛经济性状的关联研究

以6个黄牛品种502个个体为材料,利用PCR-SSCP和DNA测序相结合的方法检测脂素1(Lpin1)基因的多态性,并分析该基因多态性与秦川牛经济性状的相关性。结果发现,黄牛Lpin1基因存在3个SNPs:31735A>G、46137A>C和65969G>A,分别位于内含子1、外显子6和内含子15,其中位于外显子6的突变导致脂素蛋白质第82位的组氨酸变为脯氨酸,为错义突变。3个SNP多态位点与秦川牛的体尺和肉质性状的关联分析表明,31735A>G位点GG基因型个体的胸深、胸围、背膘厚显著高于AA和AG基因型个体(P<0.05);46137A>C位点AC和CC基因型个体的背膘厚显著高于AA基因型个体(P<0.05),CC基因型个体的眼肌面积和大理石花纹评分等级显著高于AA基因型个体(P<0.05);65969G>A位点AA基因型个体的胸深、胸围、眼肌面积和背膘厚显著高于BB基因型个体(P<0.05),BB基因型个体的大理石花纹评分等级显著高于AA和AB基因型个体(P<0.05)。可见,Lpin1基因可能是影响秦川牛眼肌面积、大理石评分和背膘厚性状的主效QTL或者是与之紧密连锁,可作为秦川牛品质改良的辅助选择标记。     

利用HRM技术对皮南牛MSTN基因C313Y位点快速分型

旨在利用高分辨率熔解(HRM)技术建立一种皮南牛MSTN基因C313Y突变的快速分型方法,进而统计MSTN基因C313Y突变在皮南牛群体中的突变频率,以及突变对生产性能的影响。测量并统计99头皮南牛(母牛)的体尺和体质量指标,然后分别利用Sanger测序法和HRM技术对皮南牛MSTN基因C313Y位点进行分型,并利用一般线性模型分析突变对体尺和体质量指标的影响。结果表明,皮南牛在3岁之后体尺和体质量指标均趋于稳定,平均体高、体斜长、胸围、尻宽、尻长和体质量分别是(127.88±3.65) cm、(154.10±6.89) cm、(181.48±8.54)cm、(46.19±2.94) cm、(50.52±2.65) cm和(471.34±53.78)kg。Sanger测序法和HRM技术对MSTN基因C313Y位点的分型结果完全一致,其中野生型(GG)、杂合型突变(GA)和纯合型突变(AA)的个体分别占8.08%、70.7%和21.21%。关联分析表明,杂合型突变(GA)和纯合型突变(AA)均能够显著提高皮南牛的体尺和体质量指标,其中纯合突变型个体和杂合突变型个体的体质量比野生型个体分别显著提高38.55%和10.32%。成功建立基于HRM的皮南牛MSTN基因C313Y位点快速分型方法,该方法对于快速组建皮南牛MSTN C313Y纯合突变群体,进而有效提高群体的体尺和体质量指标具有重要的应用价值。     

IGFBP3基因多态性与鲁西牛和晋南牛部分屠宰性状的相关性

利用PCR-RFLP技术对24头鲁西牛和19头晋南牛的IGFBP3基因多态性及与屠宰性状的关系进行了研究。结果表明,鲁西牛和晋南牛IGFBP3基因存在多态性,但只有AA、AB2种基因型,基因型频率分别为0.875/0.125和0.895/0.105,等位基因A/B的频率分别为0.938/0.062和0.948/0.052。对IGFBP3基因座基因型与19个屠宰性状进行了分析,在鲁西牛群体中,除胴体深、日增重、净肉率、屠宰率4个指标外,其它指标AB型均好于AA型,但差异不显著;在晋南牛群体中,除屠宰率、骨重、膘度、胴体胸深、后腿围、后腿宽、后腿长、腰部肉厚这8个指标外,其它指标AA型均好于AB型,差异也不显著。     

乌珠穆沁绵羊RIPK2基因多态性与生长性状的关联

【目的】基于前期绵羊肉用性状GWAS研究结果,旨在探讨RIPK2基因对乌珠穆沁绵羊生长性状的影响,找到该基因中与绵羊生长性状相关的分子标记,同时对GWAS结果进行验证。【方法】在343只乌珠穆沁绵羊试验群体中,选取其中30个个体的血液DNA样本,以相同浓度组成池DNA,设计引物对RIPK2基因外显子及其上下游1 000bp的调控区进行PCR扩增,PCR产物检测为目的条带后测序。使用DNAMAN和Chromas2软件对测序峰图进行分析,采用飞行质谱方法对检测到的SNP位点及前期GWAS得到的SNP位点进行基因型分型。使用Haploview软件对多态位点构建单倍型及连锁不平衡分析。使用SPSS （22.0）软件进行RIPK2基因SNP位点与生长性状间的关联分析。【结果】共发现了4个多态位点,A5536G的同义突变rs01位于第四外显子内,在该位点检测到三种基因型,AA基因型频率为0.42,AG基因型频率为0.45,GG基因型频率为0.13,优势等位基因为A,其频率为0.65;在第七外显子上检测到T8952C错义突变rs02,在该突变位点检测到3种基因型,其中TT基因型频率为0.82,TC基因型频率为0.16,CC基因型频率为0.02,T为优势等位基因,基因频率为0.9;在第十外显子检测到 T2836C的突变rs05,在该位点检测到两种基因型TT和CC,没有检测到杂合子基因型,TT基因型频率为0.25,CC基因型频率为0.75;上游调控区发现一个G5181C的突变rs30,有3种基因型,其中GC基因型频率为0.50,CC基因型频率为0.18,GG基因型频率为0.32,G为优势等位基因,其频率为0.58; GWAS得到的SNP位点是T4456C,在本研究中被命名为rs34,在该位点有3种基因型,其中TT基因型频率为0.49,TC基因型频率为0.37,CC基因型频率为0.14,优势等位基因T的频率为0.68。χ²适合性检验发现,除rs34位点外,其余位点均处于Hardy-Weinberg平衡状态(P＞0.05)。rs02位点处于低度多态(PIC＜0.25),其余位点处于中度多态(0.25＜PIC＜0.5)。连锁不平衡分析发现,rs01和rs02位点强连锁,在群体中共构建了3种单倍型,AT 为优势单倍型,其频率为0.645,这两个位点共构建了6 种基因型组合,其中AATT为优势基因型组合,频率为0.425。单标记关联分析表明：rs01位点的AA、AG基因型的个体和GG基因型个体在4月龄体重、胸围上差异显著（P＜0.05）,在6月龄体高、胸围上差异显著(P＜0.05)。rs02位点CC基因型个体在4月龄体重、体高、胸围和6月龄胸宽上显著优于TT、TC基因型个体（P＜0.05),在4月龄体斜长、6月龄体高和体斜长上极显著优于TT、TC基因型的个体（P＜0.01）。rs30位点上,GG基因型的个体在4月龄体重、胸围与其他两种基因型个差异显著(P＜0.05),3个基因型的个体在6月龄胸围上均有显著差异（P＜0.05）。rs34位点的3个基因型的个体仅在4月龄体重上差异显著(P＜0.05)。rs01-rs02组合基因型关联分析发现：GGCC基因型组合的个体在4月龄体重、体高、体斜长、胸围上与其他基因型之间差异显著（P＜0.05）,GGCC基因型组合的个体在6月龄体高、体斜长、胸宽上与其他基因型组合的个体差异显著（P＜0.05）。【结论】RIPK2基因对绵羊生长性状具有较显著的影响,其SNPs作为分子标记对乌珠穆沁绵羊生长性状的选育具有一定的指导意义。     

香猪生长激素基因不同基因型对生长性能的影响

利用PCR-RFLPs技术,检测香猪生长激素基因ApaI酶切位点多态性,并分析不同基因型对个体初生重、2月龄体重、4月龄体重、平均日增重、4月龄体长和4月龄胸围等生长性能的影响。结果表明,香猪生长激素基因ApaI酶切后产生3种基因型和2种等位基因,AB基因型和AA基因型香猪的4月龄体重、0￣4月龄平均日增重均极显著地低于BB基因型香猪(P<0.01),4月龄体长也显著低于BB基因型香猪(P<0.05),提示AB和AA基因型可能是香猪矮小性的有利基因型。     

鹌鹑ESR1基因的多态性与蛋品质的关联分析

为了探讨雌激素受体(ESR1)基因的多态性及其与鹌鹑蛋品质的关系,采用PCR-RFLP和直接测序法对中国黄羽鹌鹑、朝鲜鹌鹑、北京白羽鹌鹑3个群体的ESR1基因与鹌鹑蛋品质性状进行关联分析。结果表明:鹌鹑ESR1基因外显子1、外显子4、外显子8在北京白羽鹌鹑、中国黄羽鹌鹑、朝鲜鹌鹑3个群体中都检测到了CC、CT、TT三种基因型。外显子1在3个鹌鹑群体中均表现为CC基因型频率最高;外显子8在3个鹌鹑群体中均表现为TT基因型频率最高;外显子4在中国黄羽鹌鹑、朝鲜鹌鹑中TT基因型频率最高,分别为0.409、0.617,而北京白羽鹌鹑以CC基因型频率最高(0.667)。相关性分析结果显示,在3个检测群体中,外显子4的CC基因型和CT基因型的蛋黄高度和蛋黄指数显著高于TT基因型(P<0.05),TT基因型的蛋黄宽度显著高于CC基因型和CT基因型(P<0.05),CT基因型和TT基因型的蛋壳厚度显著高于CC基因型(P<0.05)。外显子8在蛋黄指数上,CC基因型显著高于CT基因型和TT基因型(P<0.05);CT基因型和TT基因型的蛋黄宽度显著高于CC基因型(P<0.05)。ESR1基因可以作为有价值的候选基因应用于蛋用鹌鹑的分子标记辅助选择。     

非遗传因素对西门塔尔牛主要经济性状的影响

为探讨非遗传因素对西门塔尔母牛主要经济性状的影响规律,利用新疆呼图壁种牛场1989—2014年间共1 492头西门塔尔牛的生产性能记录,分析了不同胎次、产犊年份、产犊季节、产犊年龄对西门塔尔牛305d产奶量、体高、硬长、软长、胸围、腹围、尻宽、尻长、腿围、管围、体重和外貌评分的影响,并进行了最小二乘分析。结果表明:不同胎次、产犊年份、产犊年龄对西门塔尔牛305d产奶量、体高、硬长、软长、胸围、腹围、尻宽、尻长、腿围、管围、体重和外貌评分有极显著的影响(P0.01);不同产犊季节对西门塔尔牛305d产奶量、体高、胸围、尻宽、尻长、腿围、管围、体重和外貌评分有极显著的影响(P0.01),对硬长、软长、腹围没有显著的影响(P0.05)。