Pig breeding is generally conducted among many herds, so EBV comparisons across populations are necessary. Genetic connectedness is required for reliable between-farm animal EBV comparisons. Five quantitative overall connectedness measures among populations have been proposed so far, coefficient of connectedness(γ*), coefficient of determination (CD) and overall indices of precision, connectedness rating, number of direct genetic links between subpopulations due to common sires and dams (GLt), and average genetic covariance (AGC) are reviewed and their properties are discussed in this paper. It is recommended to use AGC at present for measuring genetic connectedness between herds.

A resource population constructed by F2 design with Landrace and Chinese indigenous Lantang pigs was used in this study. Seven microsatellite DNA markers on chromosome 6 and USDA2.6 pig genetic linkage map were used for interval QTL mapping. The results revealed that at the position of 38-41 cM there was a chromosome-wide highly significant QTL affecting carcass backfat A thickness (P<0.01), which was closely linked with MN007 and the ratio of QTL additive variance to F2 phenotypic variance was 5.90%. At the position of 60-70 cM there were two chromosome-wide significant QTLs affecting carcass lean percentage (P<0.01) and skin and fat percentage (P<0.05), which were closely linked with MN003 and the ratio of QTL additive variance to F2 phenotypic variance were 18.44 and 3.75%, respectively. At the same position, there was a single-point QTL also closely linked with MN003 and highly significantly (P<0.01) affecting carcass lean. In addition, there were two chromosome-wide highly significant (P<0.01) QTLs affecting meat color and marbling, which were closely linked with MN13 at the position of 70-75 cM and the ratio of QTL additive variance to F2 phenotypic variance were 14.05 and 1.77%, respectively.

利用F2代设计建立了由216头F2代个体组成的长白×蓝塘猪资源群，应用PCR-RFLP方法检测F2代个体1Gf-1基因的多态性；通过固定模型方法估计了1Gf-1不同基因型的最小二乘均值，同时采用混合模型方法分析不同性状1Gf-1基因型的遗传效应，并由此计算1Gf-1基因的加性和显性效应。固定模型和混合模型方法的分析结果都表明，1Gf-1不同基因型对猪断奶后日增重有显著影响，AA型的遗传效应显著比AB型高20.58g（P=0.0347），1Gf-1基因对该性状的加性和显性效应分别为1.78g和-18.81g；对胴体组成性状也有影响，AA型和AB型对骨率的遗传效应分别极显著低于BB型5.22%（P=0.0008）和5.19%（P=0.0007），1Gf-1基因对该性状的加性和显性效应分别为-2.61%和-2.58%；AA型胴体瘦肉量的遗传效应显著比AB型少0.45ks（P=0.0264），1Gf-1基因对该性状的加性和显效应分别为0.16ks和0.61kg；AA型和AB型皮脂率的遗传效应比AB型分别高8.81%（P=0.0206）和7.64%（P=0.0431），对该性状的加性和显性效应分别为4.41%和3.245。因此，IGF-1基因的遗传效应分析说明该基因对断奶后日增重、骨率、胴体瘦肉量和皮脂率等4个性状有显著的遗传影响；而加性和显性效应估计值的大小表明，IGF-1基因的遗传效应只有在皮脂率性状上加性效应相对显性效应比较高，可以作为主基因对该性状进行有效选择。

The F2 design was used in construction of the pig resource population, and 14 economic important traits of 119 F2 offspring were measured. The polymorphisms of heart fatty acid binding protein gene (H-FABP) were detected by PCR-RFLP. The effects of different H-FABP genotypes were analyzed by a fixed model. The results showed that, the carcass composition traits were affected by H-FABP gene significantly, backfat thickness alive, carcass backfat thickness between 6th-7th rib, and average carcass backfat thickness, of different H-FABP genotypes were significantly different (P<0.05). The dominant effects on the traits demonstrated that the gene affected the carcass composition traits overdominantly. The results also showed that H-FABP gene affected the growth traits and meat quality traits, and the pH, of different H-FABP genotypes was significantly different.

采用DHPLc系统和Lahwork40图像分析软件，对大白猪和广东地方品种蓝塘猪眼肌组织差异显示E田进行鉴定，两种方法均证实了差异显示条带的真实性。结果表明：用DHPLc系统能够准确而简捷的检测不同组织中rnRNA表达的差异，是1种鉴定基因表达差异的有效方法，在研究基因表达，比较不同环境条件下动物组织的mRNA表达差异等方面具有广阔的应用前景。