Ruminant nutritionists traditionally focus on fulfilling nutrient requirements to support growth, lactation, and reproduction. Contemporary nutritional science, however, reveals a deeper role for nutrients beyond simply serving as substrates, they directly influence gene expression. This nutrient-driven modulation, termed epigenetics, significantly affects immunity, health, and longevity in dairy cows.
Epigenetics (Greek: epi-, meaning “above,” and genetics, meaning “origin”) refers to mechanisms regulating gene activity without changing the underlying DNA sequence. Simply put, epigenetics act like switches, turning genes on or off based on nutrient-derived metabolites. When these metabolites are abundant, beneficial genetic pathways activate; when scarce or imbalanced, critical pathways may become inactive, compromising health and longevity.
In this article, I explore practical ways to activate the genetic switches of epigenetics—simple strategies to help turn on beneficial genes through strategic feeding.
Epigenetic mechanisms explained
Primary epigenetic mechanisms include DNA methylation, histone modifications, and non-coding RNA regulation. Adding methyl groups to DNA sites (CpG islands), typically silences gene expression. Histones, small proteins forming nucleosomes around which DNA wraps, can undergo acetylation, methylation, and phosphorylation. These modifications alter DNA packaging: Tightly wrapped DNA suppresses genes, while loosely wrapped DNA allows gene expression. Non-coding RNAs further influence gene interpretation. These epigenetic modifications are heritable and responsive to dietary conditions.
Continue reading this article published in Feed & Additive magazine.
