The impact of genetic variants related to the fatty acid metabolic process pathway on milk production traits in Jersey cows

The synthesis of fatty acids plays a critical role in shaping milk production characteristics in dairy cattle. Thus, identifying effective haplotypes within the fatty acid metabolism pathway will provide novel and robust insights into the genetics of dairy cattle. This study aimed to comprehensively examine the individual and combined impacts of fundamental genes within the fatty acid metabolic process pathway in Jersey cows. A comprehensive phenotypic dataset was compiled, considering milk production traits, to summarize a cow’s productivity across three lactations. Genotyping was conducted through PCR-RFLP and Sanger sequencing, while the association between genotype and phenotype was quantified using linear mixed models. Moderate biodiversity and abundant variation suitable for haplotype analysis were observed across all examined markers. The individual effects of the <i>FABP3</i>, <i>LTF</i> and <i>ANXA9</i> genes significantly influenced both milk yield and milk fat production. Additionally, this study reveals novel two-way interactions between genes in the fatty acid metabolism pathway that directly affect milk fat properties. Notably, we identified that the GGAAGG haplotype in <i>FABP3</i>×<i>LTF</i>×<i>ANXA9</i> interaction may be a robust genetic marker concerning both milk fat yield and percentage. Consequently, the genotype combinations highlighted in this study serve as novel and efficient markers for assessing the fat content in cow’s milk.

脂肪酸合成过程对奶牛产奶特性的形成具有关键调控作用。因此，识别脂肪酸代谢通路中的有效单倍型，将为奶牛遗传学研究提供全新且可靠的理论视角。本研究旨在全面解析娟姗牛脂肪酸代谢通路中核心基因的单独效应与联合效应。研究整合了涵盖产奶性状的全面表型数据集，以概括奶牛在三个泌乳周期内的生产性能。采用PCR-RFLP与桑格测序法完成基因分型，并通过线性混合模型量化基因型与表型间的关联。所有检测的分子标记均呈现中等水平的生物多样性与丰富的遗传变异，适配单倍型分析需求。脂肪酸结合蛋白3（FABP3）、乳铁蛋白（LTF）和膜联蛋白A9（ANXA9）的单独效应，均对产奶量与乳脂生成具有显著影响。此外，本研究揭示了脂肪酸代谢通路中基因间全新的双向互作关系，该互作直接影响乳脂相关性状。值得注意的是，本研究发现FABP3×LTF×ANXA9互作体系中的GGAAGG单倍型，可作为兼具乳脂产量与乳脂率评估价值的可靠遗传标记。综上，本研究筛选出的基因型组合，可作为评估奶牛乳脂含量的新型高效遗传标记。