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81.
MO Jiayuan GAO Jiuyu FENG Lingli LI Yueyue TIAN Weilong LIU Xiaoxiao CHENG Feng LIANG Liang LEI Shuqiao WEN Wei LIANG Jing LAN Ganqiu 《中国畜牧兽医》2007,47(12):3965-3975
In order to identify the molecular markers related to alive litter size of Bama Xiang pigs,the genome-wide association study (GWAS) was used to map and screen the candidate genes affecting the alive litter size trait.Ear tissue samples of 297 Bama Xiang pigs with multiple parity records were collected,and DNA was extracted and genotyped by porcine 50K SNP beadchip.After quality control and genotype imputation,the alive litter size of Bama Xiang pigs were GWAS by Tassel.The results showed that the average number born alive per litter of Bama Xiang pigs increased gradually with the increasing of parity in the range of 1-9 parities.A total of 32 816 SNPs were obtained after quality control and filtration.8 SNPs related to alive litter size of Bama Xiang pigs were screened by genome-wide association analysis,which were significant at genome or chromosome level.Based on the enrichment analysis of the coding genes in the region between 500 kb upstream and downstream of the associated significant SNP loci,and the QTL regions and gene functions related to porcine reproductive traits,4 genes (CAPZB,MSH3,CITED2 and HSD17B7) were finally identified to be candidate genes related to alive litter size of Bama Xiang pigs. 相似文献
82.
选用平均体重29.6kg的三元杂(杜×大×长)生长猪144头,按随机区组设计分为6个处理。饲粮中分别添加0、100、200mg/kg硫酸铜、200mg/kg碱式氯化铜、100mg/kg小肽铜、100mg/kg复合氨基酸螯合铜(以铜含量计)。结果表明:100mg/kg小肽铜和100mg/kg复合氨基酸螯合铜均能有效提高生长猪日增重和日采食量,其促生长效果与200mg/kg硫酸铜无显著(P〉0.05)差异,而粪中铜含量分别下降了36.8%和48.4%(P〈0.05)。 相似文献
83.
96头始重(24.14±1.12)kg的杜长大三元杂交猪,随机分为4组。第1组为对照组,饲喂基础日粮(含氟量37.39mg/kg),第2、3、4组分别饲喂含氟(以NaF形式添加)量为100、150、200mg/kg的日粮,研究日粮中不同氟水平对猪生长性能和血清某些生化指标的影响,并探讨了氟在肝、肾和肌肉中的沉积,饲料氟和粪氟、血清氟、尿氟之间的相关关系。结果表明,第3、4组猪增重与对照组相比分别降低8.86%(P<0.05)和9.81%(P<0.05),料重比分别升高7.36%(P<0.05)和8.07%(P<0.05)。第4组血清钙、镁、白蛋白含量和碱性磷酸酶的活力与对照组相比分别降低了17.33%(P<0.01)、29.91%(P<0.01)、10.75%(P<0.05)和33.71%(P<0.01)。第3、4组肝、肾和肌肉氟含量与对照组相比显著增加(P<0.05)。各试验组粪氟、血清氟、尿氟含量随饲料中氟含量的增加而升高,且各组间差异极显著(P<0.001),饲料氟与粪氟、血清氟、尿氟含量相关系数分别为0.943(P<0.01)、0.911(P<0.01)和0.959(P<0.01)。 相似文献
84.
膨化与加酶玉米对断奶仔猪生长性能和肠黏膜形态的影响 总被引:1,自引:0,他引:1
通过2个饲养试验,研究了膨化及加酶处理玉米对断奶仔猪的生长性能和肠黏膜形态的影响。试验一分别用普通玉米、膨化玉米、普通玉米加酶及膨化玉米加酶为主要能量原料的饲料饲喂仔猪做4种处理,每个处理6个重复,定时记录体质量和耗料量.计算日增重、日采食量和料肉比。结果表明,膨化和加酶玉米均可提高日增重,降低料肉比。试验二分别用普通玉米、膨化玉米、普通玉米加酶及膨化玉米加酶为主要能量原料的饲料饲喂仔猪做4种处理,每个处理6个重复,分别在断奶后第14天和第28天各屠宰1头公猪。取十二指肠、空肠前、中、后段以及回肠做组织切片,观察其黏膜厚度、绒毛高度、隐窝深度和绒毛宽度。结果表明,断奶后14d,与普通玉米组相比,膨化玉米组和加酶玉米组都显著提高了十二指肠的绒毛高度,二者共同处理组使十二指肠的绒毛高度极显著提高;2种处理组都显著降低了空肠中段的隐窝深度;显著增加了十二指肠、空肠前段、后段和回肠的黏膜厚度。断奶后28d,2种处理组都显著增加了十二指肠的黏膜厚度。 相似文献
85.
对猪体细胞克隆技术中关键步骤之一的去核方法作了较深入的研究。结果表明,由本实验室改进的Willadsen去核法——二步挤压去核法,无论在去核操作成功率(73.9%)上还是在去核效率(81.2%)上都明显好于McGrath-Solter去核法(42.5%、67.4%,P〈0.05);同时,本试验还发现,卵母细胞成熟培养36h后去核组去核效率(89.1%)显著地高于成熟培养44h后去核组(55.8%,P〈0.05),而核移植重构胚的发育率2个组间无显著差异。 相似文献
86.
Characterization of a line of pigs previously selected for increased litter size for RBP4 and follistatin 总被引:1,自引:0,他引:1
C.D. Blowe K.E. Boyette M.S. Ashwell E.J. Eisen O.W. Robison & J.P. Cassady 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2006,123(6):389-395
The objective of this study was to determine if selection response for increased litter size in pigs could be partially attributed to three type 1 marker loci coding for genes known to affect litter size: oestrogen receptor (ESR), retinol‐binding protein 4 (RBP4) and follistatin (FS). In the high litter size line (LS), pigs from the largest litters, based on number of pigs born alive (NBA), were retained to parent the next generation. A randomly selected control line (LC) was maintained. Gilts were reared in litters of 10 pigs or less to minimize maternal effects. Pigs were measured at generations 10–12. Additional traits scored were number of fully formed pigs (NFF) and number of mummified fetuses (MUM). Breeding values for NFF and NBA were greater (p < 0.05) in LS than LC in generations 11 and 12, but no significant line differences were found for MUM. The A allele of the ESR locus was fixed in both lines. After adjustment for effects of genetic drift, frequency of the two alleles segregating for the FS and RBP4 loci did not differ significantly between lines. No significant additive or dominance effects of the FS markers were detected for NFF, NBA and MUM in either LS or LC. Response to selection for increased litter size could not be attributed to effects at the ESR, RBP4 or FS loci. 相似文献
87.
88.
ZHANG Shui-jun ZHU Sheng-xing LI Jie MA Xiu-xian FENG Liu-shun FAN Zheng-jun 《园艺学报》2007,23(8):1480-1483
AIM:To investigate how brain-dead state affects the heart structure and function and the effect of PKC-α in BA-Ma mini pigs.METHODS:Ten Ba-Ma mini pigs were randomized into 2 groups: brain-dead group (n=5),and control group (n=5). The brain-dead model was made by increasing intracranial pressure,while the control group was maintained anesthesia for 24 h. The concentrations of cTnT,TNF-α,IL-1β and IL-6 in serum were determined at 6,12 and 24 h after brain death. At 24 h,heart tissues were observed by HE staining and electron microscope. The expression of PKC-α was detected by immunohistochemistry and RT-PCR.RESULTS:(1) Histological changes of myocardium: flaky bleeding under endocardium and dissolution of myocardium were found in optical microscope. In electron microscope dropsical mitochondria and confluent muscle fiber were found. (2) Changes of serum cTnT: serum cTnT for brain-dead group began to increase gradually since 6 h,and were significantly higher at each time point than those in control group (P<0.05). (3) Changes of inflammatory factors: IL-1β,IL-6,and TNF-α in brain-dead group began to increase gradually since 6 h,and were significantly higher at each time point than those in control group (P<0.05). (4) Changes of PKC-α expression: PKC-α mRNA and protein expressions in brain-dead group increased significantly at 24 h (P<0.05).CONCLUSION:Brain death may evoke heart structure and functional injury,and increase the levels of inflammatory factors and PKC-α. The activation of PKC-α may participate in the process of heart injury. 相似文献
89.
This study was aimed to analyze the genetic variation of insulin-like growth factor binding protein 2 (IGFBP2) gene effect on meat quality traits in pigs. A pair of primer was designed,which based on DNA sequence of IGFBP2 gene (GenBank accession No.:BV727778). The genetic polymorphism of IGFBP2 gene was detected by PCR-RFLP in Sujiang pig, Jiangquhai pig and Landrace pig, and the association between IGFBP2 gene polymorphism and meat quality traits in three pig breeds was analyzed. The results showed that three genotypes (AA, AB and BB) were detected. The Chi-square test results showed that the genotype distribution of three pig breeds was in Hardy-Weinberg equilibrium (P > 0.05). The polymorphism information content (PIC) were moderately polymorphic in three pig breeds. According to the association analysis of different genotypes, significant difference was found in color value, intramuscular fat content and marbling, the color value (except for Jianquhai pig) and intramuscular fat content of AA genotype were significantly higher than AB and BB genotypes (P < 0.05), the marbling of AA and AB genotypes was significantly higher than BB genotype (P < 0.05). In conclusion,the polymorphism of IGFBP2 gene intron 3 had significant effects on meat quality traits, and was candidate gene for the potential impact on meat quality traits of pigs. 相似文献
90.
将选用的 12 0头杜长大杂交生长肥育猪随机分成 4组 ,3组为实验组 ,1组为对照组 .在实验组的日粮中添加 2 0 0、50 0、10 0 0 μg· kg-1烟酸铬 (以 Cr元素计 )进行为期 2个月的试验 .结果表明 :( 1)试验组日增重比对照组分别提高 11.7%、11.1%和 12 .5% ;料重比分别提高 5.5%、5.6%和 4 .2 % .( 2 )添加 Cr对血清中 K+、Na+、Cl-、总蛋白、白蛋白、脂蛋白及血红蛋白无影响 ( P>0 .0 5) ;血清中 Ca2 +、PO3-4 、尿素氮、尿酸、甘油三酯、胆固醇和血糖含量显著下降 ( P<0 .0 5) ;血清碱性磷酸酶、天门冬氨酸转氨酶、丙氨酸转氨酶含量明显升高 ( P<0 .0 5) ;磷酸肌酸激酶含量显著升高 ( P<0 .0 5) ;而乳酸脱氢酶无明显改变 ( P>0 .0 5) .( 3) Cr含量均未超过国家限量标准 .( 4 )未发现器官的组织结构和细胞形态有何改变 .由此可见 ,在生长肥育猪中添加一定量烟酸铬制剂对猪有积极正面效应 相似文献