Genetic Analysis of Feet and Leg Conformation and Proportion of Crushed Piglets in Austrian Large White and Landrace Sows

Selection for feet and leg traits can increase longevity as well as several performance traits in sows. Moreover, good feet and leg quality contributes improving animal welfare not only for sows, but also for piglets. Sows with feet and leg problems have a higher risk of crushing their piglets when lying down. Therefore, a feet and leg scoring scheme was derived and applied by trained assessors. Furthermore, piglet mortality rate by crushing was recorded. Genetic parameters as well as breeding values were estimated and the effect of the traits on piglet mortality rate by crushing was investigated. Data of 993 Large White and 299 Landrace sows of 23 nucleus farms were analyzed. Heritabilities ranged from 0.03 to 0.16 for piglet mortality rate by crushing and pastern fore legs. Some genetic correlations between feet and leg traits were significantly highly correlated (0.69 to 0.79). Sows with favorable scores for almost all feet and leg scores had higher estimated breeding values for piglet mortality rate. Higher values indicate less crushed piglets and are thus favorable. An introduction of a feet and leg scoring scheme into routine genetic evaluation may thus contribute to animal welfare improvement for sows and piglets.