Rooting is the defining behavioural characteristic of pigs — an intense, highly motivated foraging behaviour that they are compelled to perform regardless of hunger. Its denial in most commercial systems causes significant and ongoing welfare compromise.
Rooting substrate is not an optional luxury for pigs — it is the single most important welfare resource that most commercial pig systems fail to provide. The evidence that rooting is a behavioural need rather than a learned behaviour demonstrates that denying it causes genuine deprivation and frustration regardless of whether the pig has enough food. The fact that providing straw or other substrate reduces harmful behaviours by 40-80% makes the welfare case overwhelming. The barrier is practical — slurry systems are incompatible with straw — but this represents a system design failure rather than an inevitable constraint. Welfare-led system redesign, not band-aid solutions, is what pig welfare requires.