The objective of the present study was to assess hair and serum trace element and mineral levels in dairy cows in relation to daily milk yield. A total of 70 healthy 5-6-year-old Simmental cows were divided into two groups (n = 35) with high and low daily milk yield using median as a cut-off value. Hair and serum trace element and mineral content was evaluated using inductively coupled plasma mass-spectrometry. A nearly twofold difference in daily milk yield (43.8 ± 9.7 vs 21.3 ± 7.1 L/day, p < 0.001) was significantly associated with 11% lower hair Cu (p = 0.043) and 35% higher Se levels (p = 0.058) content when compared animals with lower daily milk yield. Serum trace element levels were found to be more tightly associated with milk productivity in dairy cows. Particularly, serum levels of Se and Zn were found to be 73 and 35% higher in cows with higher milk productivity in comparison to animals with lower milk production, respectively. Serum Co levels also tended to increase with higher milk productivity. Serum minerals including Ca, Mg, and P were also found to be higher in highly productive cows by 6%, 14%, and 71%, respectively. The overall regression model based on serum trace element and mineral levels accounted for 38% of daily milk production variability. Generally, improvement of essential trace element and mineral supply, as well as prevention of copper overload in dairy cows, may be considered the potential tool for modulation of milk productivity.

中文翻译：

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与每日产奶量相关的奶牛血清和毛发微量元素和矿物质水平。

本研究的目的是评估奶牛的毛发和血清微量元素和矿物质水平与每日产奶量的关系。将 70 头健康的 5-6 岁西门塔尔奶牛分为两组（n = 35），以中位数为临界值，日产奶量高和低。使用电感耦合等离子体质谱法评估头发和血清微量元素和矿物质含量。每日产奶量的近两倍差异（43.8 ± 9.7 vs 21.3 ± 7.1 L/天，p < 0.001）与头发铜含量降低 11%（p = 0.043）和硒水平提高 35%（p = 0.058）显着相关与每日产奶量较低的动物相比。发现血清微量元素水平与奶牛的产奶量更紧密相关。特别，与产奶量较低的动物相比，产奶量较高的奶牛的血清硒和锌水平分别高出 73% 和 35%。血清 Co 水平也随着产奶量的增加而增加。包括钙、镁和磷在内的血清矿物质也被发现在高产奶牛中分别高出 6%、14% 和 71%。基于血清微量元素和矿物质水平的整体回归模型占每日产奶量变异性的 38%。一般来说，改善必需的微量元素和矿物质供应，以及防止奶牛中的铜超负荷，可能被认为是调节产奶量的潜在工具。血清 Co 水平也随着产奶量的增加而增加。包括钙、镁和磷在内的血清矿物质也被发现在高产奶牛中分别高出 6%、14% 和 71%。基于血清微量元素和矿物质水平的整体回归模型占每日产奶量变异性的 38%。一般来说，改善必需的微量元素和矿物质供应，以及防止奶牛中的铜超负荷，可能被认为是调节产奶量的潜在工具。血清 Co 水平也随着产奶量的增加而增加。包括钙、镁和磷在内的血清矿物质也被发现在高产奶牛中分别高出 6%、14% 和 71%。基于血清微量元素和矿物质水平的整体回归模型占每日产奶量变异性的 38%。一般来说，改善必需的微量元素和矿物质供应，以及防止奶牛中的铜超负荷，可能被认为是调节产奶量的潜在工具。