Wojtysiak Dorota, Kaczor Urszula
Department of Reproduction and Animal Anatomy, Agricultural University of Krakow, Al. Mickiewicza 24/28, 30-059 Kraków, Poland.
Folia Biol (Krakow). 2011;59(1-2):77-82. doi: 10.3409/fb59_1-2.77-82.
The influence ofHindIII (g.2728G > A) and Bg/II (g.3996 T > C) polymorphisms at the leptin gene locus on muscle fibre characteristics and meat quality of longissimus lumborum muscle was studied in 146 barrows of the Polish Landrace breed. Leptin gene polymorphism was identified by PCR-RFLP. Fibre type percentage, fibre diameter and the following technological parameters ofmeat were also determined: pH45, pH24, Lab* colour, drip loss, water holding capacity, shear force and intramuscular fat content. Polymorphism was not detected in the locus studied in the Landrace pig herd analysed with the Bg/II restriction enzyme (g.3996 T > C). For the HindIII enzyme (g.2728G > A), there was a high frequency of GG homozygotes (0.78) and G allele (0.89), but the AA genotype was not present. Moreover, the genotypes ofleptin gene RFLP-HindIII polymorphism had no effect on intramuscular fat content and muscle fibre type percentage, but had a significant effect on muscle fibre size. Heterozygous GA fatteners had a significantly larger (P < 0.05) diameter of type IIB and type I fibres compared to homozygous GG fatteners. Generally, meat quality parameters were comparable among the examined genotypes except for water holding capacity (which was the lowest for the GG genotype) and colour lightness (L*) (which was the lightest for GA genotype). Moreover, regardless of genotype, large differences were observed between each animal in the distribution of intramuscular fat.
在146头波兰大白猪品种的公猪中，研究了瘦素基因位点上HindIII（g.2728G>A）和Bg/II（g.3996 T>C）多态性对腰大肌肌纤维特性和肉质的影响。通过PCR-RFLP鉴定瘦素基因多态性。还测定了纤维类型百分比、纤维直径以及肉的以下工艺参数：pH45、pH24、Lab颜色、滴水损失、持水能力、剪切力和肌内脂肪含量。在用Bg/II限制酶（g.3996 T>C）分析的大白猪群体中，在所研究的位点未检测到多态性。对于HindIII酶（g.2728G>A），GG纯合子频率较高（0.78），G等位基因频率较高（0.89），但不存在AA基因型。此外，瘦素基因RFLP-HindIII多态性的基因型对肌内脂肪含量和肌纤维类型百分比没有影响，但对肌纤维大小有显著影响。与纯合子GG育肥猪相比，杂合子GA育肥猪的IIB型和I型纤维直径显著更大（P<0.05）。一般来说，除持水能力（GG基因型最低）和颜色亮度（L）（GA基因型最浅）外，所检测基因型之间的肉质参数相当。此外，无论基因型如何，每头动物在肌内脂肪分布上都存在很大差异。
