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Milk Collection in the Rat Using Capillary Tubes and Estimation of Milk Fat Content by Creamatocrit
Published on: December 16, 2015
Milk metabolites and their genetic variability.
D Wittenburg1, N Melzer1, L Willmitzer2
1Institute for Genetics and Biometry, Unit Biomathematics and Bioinformatics, Leibniz Institute for Farm Animal Biology, 18196 Dummerstorf, Germany.
Journal of Dairy Science
|February 14, 2013
Summary
Milk metabolite analysis using gas chromatography-mass spectrometry reveals significant genetic variation. Heritability estimates show additive genetic effects influence milk components, aiding dairy cow breeding and health assessments.
Area of Science:
- Animal Genetics and Breeding
- Dairy Science
- Metabolomics
Background:
- Milk composition is vital for dairy cow performance, health, and breeding evaluations.
- Traditional milk analysis (fat, protein, lactose) is complemented by advanced metabolomic profiling.
- Gas chromatography-mass spectrometry (GC-MS) enables high-throughput analysis of numerous milk metabolites.
Purpose of the Study:
- To investigate the genetic variability of milk metabolites in dairy cows.
- To estimate heritability and identify modes of inheritance for milk metabolite traits.
- To explore the potential of milk metabolites as markers for breeding and disease prediction.
Main Methods:
- Analyzed 190 milk metabolite intensities from 1,295 dairy cows using gas chromatography-mass spectrometry.
- Employed a linear mixed model approach incorporating both pedigree and genomic relationships.
- Utilized 37,180 single nucleotide polymorphism markers and likelihood ratio tests to assess genetic variance components.
Main Results:
- Broad-sense heritability for milk metabolites ranged from 0 to 0.699, with a median of 0.125.
- Significant additive genetic variance was detected for highly heritable metabolites.
- Dominance genetic variance was not found to be significant for the analyzed metabolites.
Conclusions:
- Milk metabolites exhibit considerable genetic variability, influenced by additive genetic effects.
- These findings support the use of milk metabolomics in dairy breeding programs.
- Further research into locus-specific genetic effects can elucidate the molecular basis of milk quality traits.
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