Dairy cattle

Genetic basis of blood beta-hydroxybutyrate predicted from milk mid-infrared spectra in dairy cows

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Abstract

Blood beta-hydroxybutyrate (BHB) concentration is widely used as an indicator for hyperketonemia in early-lactation dairy cows, and is hence an important trait for genetic evaluation systems and selective breeding aiming to improve metabolic health of cows. However, high cost and blood sampling challenges often limit the use of direct BHB measurements. An alternative is to predict BHB phenotypes from milk mid-infrared spectral data (MIR-BHB), often routinely available at large scale for dairy cows. Based on a previous study with partly overlapping data, MIR-BHB can be predicted with moderate accuracy (R2 = 0.18 - 0.34), is moderately heritable (0.15) and has a strong genetic correlation to BHB (0.65). The objective of this study was to perform a genome-wide association study (GWAS) on MIR-BHB and identify potentially associated genes. For analysis, 51,847 MIR-BHB records of the first 70 days in milk were available for 23,909 Austrian Fleckvieh dairy cows for one or more lactations. GWAS was performed using a mixed linear model, fitting a genomic relationship matrix to estimate SNP effects for 37,165 SNP on the bovine autosomes (BTA) In total, 19 significant variants (-log10(p) > 5.9) were detected for MIR-BHB on BTA 6, 11, 19, 20 and 25. The most significant signal was found on BTA11 with a maximum -log10(p) of 45.0 in the 102.3 to 104.5 Mb region. In sum, the significant SNP accounted for 24.3% of the additive genetic variance of MIR-BHB. The identified potential candidate genes for MIR-BHB included CEL and PAEP on BTA11 and FASN, DCXR and FDXR on BTA 19. Most candidate genes were involved in biological pathways related to energy, ketone, or lipid metabolism. The findings indicate that MIR-BHB is influenced by specific genomic regions, which helps to better understand the genetic basis of this trait in Fleckvieh cows, and supports its potential as a large-scale indicator of metabolic health being incorporated in genomic selection programs.

Keywords: 2026

How to Cite:

Gruber, S., Ho, P., Khansefid, M., Xiang, R., Fuerst-Waltl, B., Köck, A., Egger-Danner, C., Schwarzenbacher, H. & Sölkner, J., (2026) “Genetic basis of blood beta-hydroxybutyrate predicted from milk mid-infrared spectra in dairy cows”, World Congress on Genetics Applied to Livestock Production Digital Archive 2026(1): 2285421. doi: https://doi.org/10.31274/wcgalp.23696

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