Developmental Programming and Postnatal Modulations of Muscle Development in Ruminants

Area of Science:

• Ruminant skeletal muscle development
• Developmental programming
• Nutritional epigenetics

Background:

• Skeletal muscle development in ruminants is complex, involving genetic, nutritional, epigenetic, and endocrine factors.
• Maternal nutrition during gestation plays a critical role in fetal myogenesis and postnatal muscle growth.

Purpose of the Study:

• To review the influence of maternal nutrition on fetal myogenesis and satellite cell dynamics in ruminants.
• To examine the expression of myogenic regulatory factors (MYF5, MYOD1, MYOG) under varying nutritional conditions.
• To synthesize current knowledge on skeletal muscle programming from prenatal development to postnatal growth.

Main Methods:

• Review of studies in sheep and cattle focusing on maternal nutrition effects.
• Analysis of satellite cell dynamics and myogenic regulatory factor expression.
• Examination of genetic, hormonal, and environmental influences on muscle development.

Main Results:

• Nutrient restriction or overnutrition alters offspring muscle fiber number, size, and gene regulation.
• Satellite cells, activated by PAX7, MYOD, and MYF5, are crucial for postnatal muscle hypertrophy.
• Hormonal signaling (GH-IGF1 axis, thyroid hormones) and epigenetic mechanisms (CARM1, miR-31) modulate satellite cell function.
• Genetic variants (e.g., myostatin mutations) impact muscle mass but can affect reproduction.

Conclusions:

• Integrated approaches combining maternal diet, molecular breeding, and precision livestock management are essential.
• Optimizing skeletal muscle programming enhances meat quality and production sustainability in ruminants.
• Understanding developmental trajectories is key to improving ruminant meat production systems.