The critical post-weaning period and welfare interventions that improve outcomes
The nursery phase — typically 3-10 weeks of age after weaning — is one of the most welfare-challenging periods in commercial pig production. Piglets face simultaneous stressors: separation from the sow, social regrouping with unfamiliar pigs, dietary transition from milk to solid feed, and a new physical environment. This stress cascade causes significant welfare harm and sets up long-term health and behavioral trajectories.
Social disruption: Commercial weaning mixes litters, requiring establishment of new dominance hierarchies through fighting. Injuries, stress, and subordinate pig welfare are significant concerns.
Thermoregulation: Newly weaned piglets lose the thermal buffering of the sow; nursery temperature management is critical. Huddling and shivering indicate inadequate temperature.
Feed transition: Palatability, digestibility, and dietary form affect how quickly piglets begin eating. Early feed intake is the strongest predictor of nursery welfare and performance.
Environmental complexity: Barren nursery pens cause boredom-related behaviors from the first week. Simple enrichment (ropes, chains, rubber toys) provided from day 1 dramatically reduces aggression and improves behavioral welfare.