orty-one percent of the sows showed difficulties in lying down. Overall, each of the lying-down behaviour problems was performed by 10–15% of the sows in the 10 herds, apart from abnormal lying-down behaviour, which occurred in 2.5% of the sows. The mean occurrences of lying-down behaviours diverging from normal lying-down behaviour observed during six visits in the 10 herds are illustrated in