Pigs have a powerful rooting drive that requires appropriate substrate to satisfy, yet legal minimums leave many pigs without meaningful rooting material.
The rooting drive in pigs is one of the most persistent and motivated behavioural tendencies in farmed animals. When suitable substrate is absent, pigs direct this drive toward other pigs in damaging behaviours including ear biting and tail biting. Legal minimum enrichment requirements in the EU and UK have been widely criticised for permitting objects that do not satisfy rooting motivation. Research consistently shows that destructible, chewable, rootable material provided in quantities that allow sustained engagement is required to genuinely satisfy this behavioural need. Straw is the most comprehensively validated substrate and provides thermal comfort and foraging stimulation in addition to rooting.