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.     

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.     

Piglet Diarrhea and Technology Transfers to Prevent E. coli Infection at Small-Holder Pig Farms in Binh Dinh,Vietnam

The study aims at finding alternative interventions for the prevention ofE. coli infection in piglets so as to boost farmers＇ benefits and improve environment in the area. Data were collected from one experimental group consisting of 210 small pig holder farms and one control group of 70 farms. All of 280 litters and sows were analyzed and the techniques of early vaccination at 60-80 d of pregnant （time 1） were applied and repeated after 10 d with E. coli vaccine to produce antibodies through milk. The percentage of piglets with diarrhea caused by E. coli significantly decreased from 75.7% to 18.9%. Injection of E. coli vaccine for the pregnant sows created antibodies for young piglets through colostrums. The treatment of E. coli cost 45,420 Vietnam Dong （VND） per litter in the experimental group and that was 156,000 VND/litter in the control group. Use of betel-bokashi （bio-product as plant antibiotics and Lactobacillus） to treat piglet diarrhea was proved safe and effective. Litter size and average weight at birth and weaning were improved significantly （P 〈 0.05）. The average weaned weight of piglets and sows were 11.2 kg and 118.6 kg in the experimental group, compared to 9.4 kg and 89.9 kg in the control group, respectively. Piglets in the experimental group had good health, no diarrhea and a shorter weaning time （2 d） and mating interval 2.22 days earlier than those in the control group. The average profit of 210 households was significantly higher in the experiment group： feed-cost was much lower than that in the control group. Small-holder farms implementing the experiments of applying the techniques received more financial profit, which was 1,502,000 VND per year per sow, while those who did not apply the techniques gained only 223,000 VND per year per sow.     

Effect of Weaning Ages on Pancreatic and Intestinal Chymotrypsin Activity in Piglet

Twelve litters of new born piglets were divided randomly into groups Ⅰ, Ⅱ, Ⅲ and Ⅳ, and weaned at 17, 21, 28 and 35 days of age, respectively, to determine the effect of weaning age on pancreatic and intestinal chymotrypsin activity in piglets. The results showed that the relative and specific activity of pancreatic chymotrypsin increased significantly 12h after weaning compared with that of sucking piglets at the same age and then decreased and remained low for 2 - 3 weeks after weaning. Total pancreatic chymotrypsin activity had no change with the increase of pancreas weight during day 18 - 50 regardless of weaning (P ＞0.05). Chymotrypsin activity of jejunum had the same change as that of pancreas during sulking stage.Jejunum chymotrypin activity decreased in the first week post-weaning in the piglets weaned before day 28, but had no change in groups weaned at 28 or 35 days. The earlier the weaning age, the longer the restoring time.Chymotrypsin activity in jejunum is more sensitive to the effects of weaning age than in duodenum and ileum.     

Effect of Eliminated the Breeding Pigs with Unqualified CSFV Antibody on Sows＇ Reproductive Performance and Pigs＇ Growth Performance

[Objective] The aim was to explore the effect of eliminated the breeding pigs with unqualified CSFV antibody on sow’s reproductive performance and pig’s growth performance so as to provide a scientific basis for the eliminating of the breeding pigs with unqualified CSFV antibody in large-scale pig farms.[Method] Serum samples from three scale pig farms were collected and tested with HerdChek CSFV-ELISA kit,then provided a certain scientific basis for scale pig farm to eliminate the unqualified(antibody blocking rate<50%)breeders after booster immunization.[Result ] After eliminating the breeding pigs with unqualified CSFV antibody,the average litter number of piglet in three pig farms(A,B,C)were increased by 0.29(P<0.05),0.40(P<0.01),0.39(P<0.01)respectively;the average number of survival piglets were increased by 0.54(P<0.01),0.35(P<0.01),0.62(P<0.01)respectively;the average litter number of weaned piglets were increased by 0.65(P<0.01),0.71(P<0.01),0.81(P<0.01)respectively.The difference in weight gain of piglet at 30-60 d of age was extremely significant(P<0.01),but inconspicuousness for the swine pregnancy rate,the survival rate of weaned piglet and piglet at 30-60 d of age.[Conclusion] The eliminating the breeding pigs with unqualified CSFV antibody can significantly improve the performance of breeder and piglets.     

The Effects of Mx1 Locus on Immunity Tracts Components in Large White×Meishan F2 Offspring

The mouse Myxovirus resistance protein 1 (Mx1) is known to be sufficient to confer resistance to influenza viruses, and genes encoding Myxovirus resistance protein 1 (Mx1) is, therefore, an interesting candidate gene for disease resistance in farm animals. The porcine Mxl gene has already been identified and characterized based on its homology with mouse Mxl; the full-length coding region of the pig Mxl gene spans 2 545 bp (M65087) and is organized into 17 exons compared with the human ortholog mRNA. In this study, the exons 9, 10, 11 and introns 6, 9 of the porcine Mxl gene were cloned and sequenced; two SNPs were identified in exons 9, 10, 11 but none of the SNPs led to an amino acid exchange, and the other eleven variants were detected in introns 6 and 9, respectively. Differences in allele frequency among Meishan, Large White, Tibetan, Tongcheng, Huainan, and Duroc pigs were observed within intron 9, of which an A → G substitution at position 186 was detected as an Msp Ⅰ PCR-restriction fragment length polymorphism (PCR-RFLP). The association analysis using the Large White×Meishan F2 offspring suggested that the Mxl genotype was associated with variation in several immunity traits that are of interest in pig breeding. However, further investigations in more populations are needed to confirm the above concept.     

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-1 gene, and the 2nd exon, the 3rd exon of the 1GFBP3 gene. Two polymorphisms, an A-to-G transition in the 2rid exon of the IGF-Ⅰ gene and a T-to-C transition in the 2rid 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 IGFBP3 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） em 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.     

猪POU1F1基因启动子区多态分析及其与生长性状的关联

 【目的】获得猪POU1F1基因启动子区的多态信息,揭示其在不同品种中的分布特点,阐明其与生长性状的关联性。【方法】采用PCR克隆、DNA测序和PCR-RFLP技术进行POU1F1基因启动子区多态分析,利用一般线形模型分析其与生长性状的关联性。【结果】在POU1F1基因1.5 kb的启动子区域内发现5个多态位点;其中,5 bp短片段插入或缺失突变的A等位基因频率在引入品种猪中最高,在培育品种中中等,在中国地方品种最低。一般线形模型分析表明,该多态位点与猪的生长性状存在显著相关。多重比较分析发现,AA基因型个体的体高、体长、胸围和体重显著高于AB和BB基因型个体（P＜0.05）,而AB和BB基因型个体的体高、胸围和体重差异不显著（P＞0.05）,但AB基因型个体的体长显著高于BB基因型个体（P＜0.05）。【结论】5 bp短片段插入或缺失突变的A等位基因是生长性状的优势等位基因,是生长性状可能的分子标记。     

美系大白猪雌激素受体基因的多态性分析

雌激素受体（estrogen receptor,ESR）能调控雌激素的合成,影响繁殖性能。试验采用PCR-RFLPs技术分析了上海市种猪场关系大白猪核心群的ESR基因的多态性,采用SAS统计分析软件分析了其多态性与母猪繁殖性能的相关性。结果表明：①群体中ESR基因的A和B等位基因的频率分别为39．66％和60．34％。②初产胎次中,BB基因型的总产仔数（TNB）与AA基因型和AB基因型的差异均达到显著水平（P〈0．05）;BB基因型的产活仔数（NBA）与AA基因型的差异达到显著水平（P〈0．05）;BB和AA纯合子间TNB和NBA分别相差2．82和2．28头。③经产胎次,BB基因型的总产仔数（TNB）和产活仔数（NBA）与AA基因型和AB基因型的差异均达到显著水平（P〈0．05）;对于母猪每窝的TNB和NBA,BB纯合子比AA纯合子分别多1．79和2．39头。无论初产胎次或经产胎次,ESR位点的总产纾数和产活仔数都呈现AA〈AB〈BB趋势;ESR基因型的影响在初生窝重和21日龄窝重之间的差异不显著（P〉0．05）;但是以上2个性状在ESR基因的3种基因型间存在BB〉AB〉AA的趋势。以上结果说明,这个种猪群的总产仔数和产活仔数偏高,这与其ESR基因的有利基因B频率较高、AB型和BB型个体多正好吻合．因此可应用分子标记辅助选择（MAS）的方法来提高母猪的繁殖性能．     

猪CACNA1S基因部分序列多态性检测及其与肉质性状的关联分析

采用PCR-SSCP技术,对30头苏钟猪和97头金华与皮特兰杂交F2代(JPF2)猪CACNA1S基因进行多态性检测,结合肉质性状作关联分析。结果表明:在猪CACNA1S基因1 234 bp核酸序列中,检测到25个单核苷酸突变点(SNP);关联分析结果显示,引物1S-65的AA、BB基因型对后腿肌肉重存在显著影响(P<0.05),AB基因型对后腿pH存在显著影响(P<0.05);引物1S-66的BB、BC基因型对蹄重存在极显著影响(P<0.01)。     

猪NCOA1基因PCR-RFLP多态性分析（摘要）（英文）

[目的]研究猪NCOA1基因的PCR-RFLP多态性,为猪的分子育种和标记辅助选择提供理论依据。[方法]以81头山东寿光六和原种猪场的长白猪为研究对象,采取常规酚-氯仿抽提法从猪耳组织提取基因组DNA,以基因组DNA为模板进行PCR扩增获得440 bp的NCOA1基因目的片段,利用限制性内切酶RsaⅠ对PCR产物进行酶切和琼脂凝胶电泳检测,并计算各等位基因频率和基因型频率。[结果]琼脂糖电泳检测酶切产物出现3种基因型：AA型（1条带：440 bp）、AB型（3条带：440、282、158 bp）、BB型（2条带：282、158 bp）;基因型频率分别为0.54、0.43和0.03;A和B 2个等位基因的基因频率分别为0.76和0.24。[结论]该研究猪群中,A为优势等位基因,AA基因型频率较高。     

松辽黑猪雌激素受体基因对部分繁殖性状的影响

以松辽黑猪为研究对象,采用PCR-RFLPs方法检测其雌激素受体(ESR)基因的PvuⅡ多态性,分析了该基因与产仔数及其他繁殖性状之间的关系。结果表明:ESR基因型间总产仔数(TNB)和产活仔数(NBA)差异显著(P<0.05),BB和AA纯合子间TNB和NBA分别相差2.395和2.250头;各基因型在初生窝重、20日龄重、60日龄重之间差异不显著(P>0.05)。     

秦川牛及其杂种牛POU1F1基因多态与生长性能相关性

 本研究首次利用PCR-RFLP技术研究相同季节4月（±10 d）龄纯种秦川牛（QQ）及杂种牛秦安（AQ）、秦德（DQ）、秦利(LQ) 4个群体164个个体POU1F1基因多态性及其与体重、体尺等生长性状指标之间的相关性。结果表明， QQ及AQ、DQ、LQ群体POU1F1-HinfI基因座的451 bp 的PCR产物被限制性酶HinfI消化后表现多态性，它们的等位基因A/B频率分别为：0.232/0.768、0.333/0.667、0.178/0.822和0.181/0.819，且均处于Hardy-Weinberg平衡状态。同时，4个群体POU1F1基因座不同基因型与体重、体尺等生长性状指标相关分析的结果表明，4个群体内AB、BB基因型个体在胸围、十字部高指标上显著高于群体AA型个体（P＜0.05），即BB、AB＞AA（P＜0.05），可作为秦川牛体尺指标(胸围、十字部高)候选基因之一。但在体长指标上均无显著差异（P＞0.05），所以不宜作为体长指标候选基因。初步认为BB基因型为优势基因型，相应地B为优势等位基因，对选择有正向效应。     

猪NCOA1基因PCR-RFLP多态性分析

[目的]研究猪NCOA1基因的PCR-RFLP多态性,为猪的分子育种和标记辅助选择提供理论依据。[方法]以81头山东寿光六和原种猪场的长白猪为研究对象,采取常规酚-氯仿抽提法从猪耳组织提取基因组DNA,以基因组DNA为模板进行PCR扩增获得440bp的NCOA1基因目的片段,利用限制性内切酶RsaⅠ对PCR产物进行酶切和琼脂凝胶电泳检测,并计算各等位基因频率和基因型频率。[结果]琼脂糖电泳检测酶切产物出现3种基因型：AA型（1条带：440bp）、AB型（3条带：440、282、158bp）、BB型（2条带：282、158bp）;基因型频率分别为0.54、0.43和0.03;A和B2个等位基因的基因频率分别为0.76和0.24。[结论]该研究猪群中,A为优势等位基因,AA基因型频率较高。     

MC4R基因在淮猪中的多态性及其与生长性状和背膘厚的相关性

[目的]分析MCAR基因多态性与生长速度及背膘厚性状的遗传关系。[方法]采用PCR-Taq I-RFLP技术,检测淮猪新品系165头个体在MC4R基因D298N主效位点的遗传变异,统计分析MCAR基因型与日增重和活体背膘厚性状的关联性。[结果]结果表明,淮猪新品系猪群中存在着丰富的MC4R基因多态性,其AA型个体的生长速度明显快于BB型个体（P〈0．01）;从型个体的活体背膘厚明显比BB型个体薄（P〈0．05）;AB型个体均处于中间。[结论]该研究进一步验证了MC4R基因对猪生长肥育性状的影响效应,为MG4R基因作为淮猪新品系的分子遗传标记提供可能性。     

FSHβ基因多态性及对不同品种猪繁殖性状的影响

选取FSHβ基因为影响猪繁殖性状候选基因,对8个猪种906头猪进行FSHβ基因的多态性分析,并采用最小二乘法分析了其对总产仔数、产活仔数和妊娠期的遗传效应。结果显示,FSHβ基因在嘉兴黑猪、巴马香猪、金华猪和八眉猪中几乎只有A等位基因,在美系杜洛克和嵊县花猪中以B等位基因为主,只有在大约克、长白、台系杜洛克中A,B等位基因均衡分布。遗传效应分析表明,在初产美系杜洛克猪中,BB基因型妊娠期比AB型缩短0.94 d（P<0.01）;在初产大约克猪中,BB基因型妊娠期比AA型缩短1.61 d（P<0.01）;在经产长白猪中,AB型产仔数和产活仔数分别比BB型多了227头（P<0.05）和231头（P<0.05）。总体而言,FSHβ基因对不同品种母猪繁殖性能效应各有差异,在初产美系杜洛克和大约克中BB基因型妊娠期更短,在经产长白猪中AB型产仔数和产活仔数更多。     

玉山黑猪ESR和FSH-β基因多态性及相关性状的研究

采用PCR-RFLP方法对玉山黑猪的ESR基因和FSH-β基因多态性进行检测,并分析其与繁殖性能间的关系。结果表明,ESR基因的3种基因型AA、AB、BB在玉山黑猪中的频率分别为0.417、0.300、0.017,各基因型对应的产仔数存在差异,总体表现BB>AB>AA,其中初产仔猪数BB型多于AA型1.21头,多于AB型0.91头;BB型经产仔猪数也高于AB型和AA型,但3种基因型之间差异不显著。FSH-β基因的3种基因型AA、AB、BB在玉山黑猪中的频率分别为0.567、0.333、0.100,各基因型对应的产仔数存在差异,总体表现BB>AB>AA,初产仔猪数BB型多于AA型0.80头(P<0.05),多于AB型0.43头(P>0.05);BB型的经产仔猪数也是3种基因型中最高的,但彼此之间差异不显著。ESR和FSH-β基因在初产仔猪数及经产仔猪数上都具有显著的加性遗传效应(P<0.05)。