Epigenetic aging in cows is accelerated by milk production

Area of Science:

• Epigenetics
• Mammalian Biology
• Animal Science

Background:

• DNA methylation is a key biomarker for predicting age in mammals, leading to the development of 'epigenetic clocks'.
• Epigenetic clocks correlate DNA methylation patterns with chronological age.

Purpose of the Study:

• To develop and validate an epigenetic clock for age prediction in domesticated cows (Bos Taurus).
• To investigate factors that may influence the rate of epigenetic aging in cows.

Main Methods:

• Targeted bisulfite sequencing was used to analyze blood DNA methylation data from 96 cows (88 adults, 8 calves).
• DNA methylation was measured across approximately 3,000 conserved mammalian genomic regions.
• Statistical analysis identified significant associations between DNA methylation changes and chronological age.

Main Results:

• An epigenetic clock was successfully constructed, predicting cow age with an accuracy of within nine months.
• Milk production levels were identified as a significant factor moderating epigenetic age.
• Higher milk production was associated with an accelerated rate of epigenetic aging.

Conclusions:

• Epigenetic clocks are effective tools for age prediction in cows.
• The physiological stress associated with high milk production may accelerate epigenetic aging in dairy cows.
• This finding has implications for understanding the health and productivity of livestock.