The objective of this paper was to assess the genetic variability of the detailed fatty acid (FA) profiles of Danish Holstein (DH) and Danish Jersey (DJ) cattle populations. We estimated genetic parameters for 11 FA or groups of FA in milk samples from the Danish milk control system between May 2015 and October 2016. Concentrations of different FA and FA groups in milk samples were measured by mid-infrared spectroscopy. Data used for parameter estimation were from 132,732 first-parity DH cows and 21,966 first-parity DJ cows. We found the highest heritabilities for test day measurements in both populations for short-chain FA (DH = 0.16; DJ = 0.16) and C16:0 (DH = 0.14; DJ = 0.16). In DH, the highest heritabilities were also found for saturated FA and monounsaturated FA (both populations: 0.15). Genetic correlations between the fatty acid traits showed large differences between DH and DJ for especially short-chain FA with the other FA traits measured. Furthermore, genetic correlations of total fat with monounsaturated FA, polyunsaturated FA, short-chain FA, and C16:0 differed markedly between DH and DJ populations. In conclusion, we found genetic variation in the mid-infrared spectroscopy-predicted FA and FA groups of the DH and DJ cattle populations. This finding opens the possibility of using genetic selection to change the FA profiles of dairy cattle.

本文的目的是评估丹麦荷斯坦（DH）和丹麦泽西（DJ）牛种群的详细脂肪酸（FA）谱的遗传变异性。我们估计了2015年5月至2016年10月之间来自丹麦牛奶控制系统的牛奶样品中11种FA或FA组的遗传参数。通过中红外光谱法测量了牛奶样品中不同FA和FA组的浓度。用于参数估计的数据来自132,732头第一胎DH奶牛和21,966头第一胎DJ奶牛。我们发现在两个种群中，短链FA（DH = 0.16; DJ = 0.16）和C16：0（DH = 0.14; DJ = 0.16）的最高测试日遗传力。在DH中，饱和FA和单不饱和FA的遗传力最高（两个种群均为0.15）。脂肪酸性状之间的遗传相关性显示，DH和DJ在特别是短链FA和其他FA性状之间存在很大差异。此外，DH和DJ人群之间总脂肪与单不饱和FA，多不饱和FA，短链FA和C16：0的遗传相关性显着不同。总之，我们在中红外光谱预测的DH和DJ牛种群的FA和FA组中发现了遗传变异。这一发现为利用遗传选择改变奶牛FA轮廓提供了可能性。我们在DH和DJ牛种群的中红外光谱预测的FA和FA组中发现了遗传变异。这一发现为利用遗传选择改变奶牛FA轮廓提供了可能性。我们在DH和DJ牛种群的中红外光谱预测的FA和FA组中发现了遗传变异。这一发现为利用遗传选择改变奶牛FA轮廓提供了可能性。