Abstract

Livestock specialized cattle breeds combining high energy for both growth and fattening performance are successfully used for high-quality beef production. The use of DNA markers as the additional criteria for sampling and mating the animals allows us to increase the efficiency of selection processes along with improving the meat characteristics of cattle. The objective of the survey was to estimate the effects of leptin gene polymorphism on the growth rates of youngstock and the product quality of beef cattle. The practical science experiment was carried out in 2014–2017. The fattening Hereford and Limousin bull calves (114 and 111 animals, respectively) were genotyped with the technique of polymerase chain reaction (PCR) and subsequent PCR-restriction fragment-length polymorphism analysis (SNP LEP-A422B). A similar genotype distribution among the animals was revealed. Homozygous genotype LEP^AA (47.34% and 52.25%, respectively) and allele LEP⁴ (frequencies of occurrence are 0.68 and 0.71, respectively) are more frequent. The liveweight in both cattle breeds with genotype LEP^AA tended to increase at the ages of 8, 12, 16, and 20 months. In addition, an insignificant predominance in body measurements used to assess the proportions of their body parts was ascertained. The analysis of the body conformation indices could indicate harmonious animal development and prove the well-expressed beef forms in the youngstock of all the genotypes for the leptin gene. The postslaughter assessment allowed us to reveal the tendency to increasing the values for the preslaughter liveweight, the hot carcass weight, and the slaughter weight. In addition, the increased carcass yield was recorded in the Hereford bull calves with genotype LEP^AA. The surveys ascertained a significant relationship between the analyzed polymorphism and the increases in the internal crude fat weight and the fat yield in the carcasses of bull calves with genotypes LEP^AB and LEP^BB. The analysis of the morphological composition of Hereford bull calf carcasses revealed a significant relationship between genotype LEP^BB and fat contents. Therefore, SNP LEP-A422B genotyping may be used in Hereford and Limousin cattle breeding to improve the meat quality parameters.

中文翻译：

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瘦素基因多态性对肉牛生产性能的影响

摘要

结合了高能量用于生长和育肥性能的家畜专用牛品种已成功用于高质量牛肉生产。使用DNA标记作为对动物进行采样和交配的附加标准，使我们能够提高选择过程的效率，同时改善牛的肉类特性。该调查的目的是评估瘦素基因多态性对肉牛生长率和肉牛产品质量的影响。实用科学实验于2014–2017年进行。使用聚合酶链反应（PCR）和随后的PCR限制性片段长度多态性分析（SNP LEP-A422B）技术对育肥的赫里福德和利穆赞牛犊（分别为114和111只动物）进行基因分型。揭示了动物之间相似的基因型分布。纯合基因型LEP ^AA（分别为47.34％和52.25％）和等位基因LEP ⁴（发生频率分别为0.68和0.71）更为频繁。两个LEP ^AA基因型牛的活重在8、12、16和20个月大时往往会增加。此外，确定了用于评估其身体部位比例的人体测量中的微不足道的优势。身体构象指标的分析可以表明动物的和谐发展，并可以证明瘦素基因的所有基因型的年轻种群中表达良好的牛肉形式。屠宰后评估使我们能够揭示出增加屠宰前活重，热hot体重量和屠宰体重值的趋势。另外，基因型LEP ^AA的赫里福德牛犊的recorded体产量增加。调查确定了分析的多态性与基因型LEP ^AB和LEP ^BB的牛犊the体的内部粗脂肪重量和脂肪产量的增加之间存在显着关系。对赫里福德公牛犊牛尸体的形态组成的分析表明，基因型LEP ^BB与脂肪含量之间存在显着关系。因此，SNP LEP-A422B基因分型可用于赫里福德和利穆赞牛的育种，以改善肉质参数。