Weaning is a significant welfare event for both calves and cows. The abrupt separation of cow and calf causes acute behavioural and physiological stress responses that can persist for several days. Understanding and mitigating this stress is an important welfare priority in both beef and dairy systems.
Both cows and calves display measurable stress at weaning: elevated cortisol, increased vocalisation (lowing), reduced feeding, walking fence lines, and impaired immune function. Calves show acute grief-like responses. In beef systems, calves may lose weight in the immediate post-weaning period. The behavioural disturbance typically peaks in the first 48-72 hours.
Abrupt weaning (sudden complete separation) is the most common method but causes the highest welfare cost. Research supports gradual weaning approaches:
Minimising concurrent stressors at weaning improves welfare outcomes. Best practice includes: avoid weaning at the same time as transport, castration, dehorning, or vaccination where possible. Ensure adequate nutrition and water access in the post-weaning pen. Familiar companions reduce isolation stress. Good stockmanship — quiet, low-stress handling — is especially important around weaning.
Dairy calves are typically separated from their dams within hours or days of birth. Early separation causes acute stress in both cow and calf. Extended suckling programmes (allowing calves to suckle for several weeks before weaning) improve calf welfare and socialisation, though require careful management of milk allocation and mastitis risk. Research is ongoing into the optimal separation age that balances welfare and practicality.