Animal Science Unit, Gembloux Agro-Bio Tech, University of Liège, 5030 Gembloux, Belgium.
J Dairy Sci. 2010 Apr;93(4):1722-8. doi: 10.3168/jds.2009-2614.
The aim of this study was to estimate the genetic parameters of the mid-infrared (MIR) milk spectrum represented by 1,060 data points per sample. The dimensionality of traits was reduced by principal components analysis. Therefore, 46 principal components describing 99.03% of the phenotypic variability were used to create 46 new traits. Variance components were estimated using canonical transformation. Heritability ranged from 0 to 0.35. Twenty-five out of 46 studied traits showed a permanent environment variance greater than genetic variance. Eight traits showed heritability greater than 0.10. Variances of original spectral traits were obtained by back transformation. Heritabilities for each spectral data points ranged from 0.003 to 0.42. In particular, 3 MIR regions showing moderate to high heritability estimates were of potential genetic interest. Heritabilities for specific wave numbers, linked with common milk traits (e.g., lipids, lactose), were similar to those estimated for these traits. This research confirms the genetic variability of the MIR milk spectrum and, therefore, the genetic variation of milk components. The objective of this study was to better understand the genetics of milk composition and, maybe in the future, to select animals to improve milk quality.
本研究旨在估计中红外（MIR）奶谱的遗传参数，每个样本用 1060 个数据点表示。通过主成分分析降低性状的维度。因此，使用 46 个主成分来描述 99.03%的表型变异性，创建 46 个新的性状。使用典型变换估计方差分量。遗传力范围从 0 到 0.35。在所研究的 46 个性状中，有 25 个表现出永久性环境方差大于遗传方差。有 8 个性状的遗传力大于 0.10。原始光谱性状的方差通过反向变换获得。每个光谱数据点的遗传力范围从 0.003 到 0.42。特别是，3 个显示出中等到高遗传力估计值的 MIR 区域具有潜在的遗传兴趣。与常见牛奶性状（如脂肪、乳糖）相关的特定波数的遗传力与这些性状的估计遗传力相似。这项研究证实了 MIR 牛奶光谱的遗传可变性，因此也证实了牛奶成分的遗传变异性。本研究的目的是更好地了解牛奶成分的遗传学，也许在未来可以选择动物来提高牛奶质量。
