Modern dairy cows are typically culled at 3-4 lactations (around 5-6 years old), far short of their potential lifespan, due to production system pressures.
High-producing dairy cows are metabolically stressed during peak lactation. Energy deficit causes body condition loss, immunosuppression, and increased disease susceptibility. Lameness, mastitis, and reproductive disorders accumulate over lactations. Early culling means most cows spend their entire lives in a metabolically compromised state. Extended longevity requires lower peak yields and better preventive health management.