温岭草鸡GH基因多态性及其与生长和屠体性状的相关性研究

Correlation between the Genetic Polymorphisms of GH Gene and the Growth and Carcass Traits in Wenling Native Chickens

以温岭草鸡优质、中速和快大3个品系为试验材料,采用PCR-RFLP方法,研究其生长激素(GH)基因的多态性及其对生长和屠体性状的影响。结果表明:(1)PCR产物酶切得到AA、AB、BB、CC、AC和BC共6种基因型。优质系(Ⅰ)中,C基因频率最高,A基因频率最低;中速系(Ⅱ)中,各等位基因频率接近;快大系(Ⅲ)中,B基因频率最低,A、C基因频率接近。(2)3个品系PIC值均大于0.5,χ2检验显示3个品系中,6种基因型分布差异极显著(P<0.01);Hardy-Weinberg平衡检验表明,品系Ⅰ和Ⅱ符合平衡定律,品系Ⅲ不符合。(3)GLM分析表明,基因型对全净膛重、腿肌重和腹脂重影响显著(P值分别为0.039、0.047、0.016),对活重、屠体重、半净膛重及胸肌重影响不显著(P>0.05)。多重比较显示,BC基因型的活重、屠体重、半净膛重、全净膛重、胸肌重和腿肌重的平均值最大,AA基因型最小;BB基因型的腹脂重平均值最大,AA基因型最小,二者差异极显著(P<0.01)。

Genetic polymorphisms of GH gene and its association with growth and carcass traits in 3 lines of Wenling native chickens were studied by the PCR-RFLP method. The results showed that 6 genotypes of AA, AB, BB, CC, AC and BC were detected in PCR products. In line Ⅰ, the frequency of allele C was the highest, allele A was the lowest; In line Ⅱ, the frequency of allele A, B and C were near each other; In line Ⅲ, allele B and C had similar higher frequency. All the 3 lines had prolific polymorphism information （PIC〉0.5）. χ^2 test indicated that the distribution of 6 genotypes in 3 lines had significant difference （P = 0.001）. Hardy-Weinberg test revealed that line Ⅰ and Ⅱ were in Hardy-Weinberg balance, while line Ⅲ wasn＇t . The GLM analysis showed that GH gene had significant effects （P 〈 0.05） on eviscerated weight, leg muscle weight, abdominal fat weight, while have no significant effects on live weight, slaughter weight, semieviscerated weight and breast muscle weight （P 〉 0.05）. Multiple comparisons showed that genotype BC had the biggest mean value of live weight, slaughter weight, semi-eviscerated weight, eviscerated weight, breast muscle weight and leg muscle weight, while AA had the smallest value. Genotype BB had the biggest mean value of abdominal fat, while genotype AA had the smallest value, they differ from each other significantly（P 〈 0.01）.