Sow responsiveness towards external disturbances and concurrent postural changes are proposed to be an
\nimportant cause of early piglet crushing. The aim of the present study was to assess whether loose housed
\nsows change their responsiveness over time within the first 24 h after birth of the first piglet upon exposure to
\ndifferent types of human contact and towards piglets\u2019 scream. The responsiveness of the sows (n = 17) was
\nscored during: (i) blood sampling of the sow during 24 h after the onset of parturition, (ii) human handling of
\na piglet at 0, 30 min, 1, 2, 4, 8 and 24 h after birth, (iii) screaming when a piglet was trapped underneath the
\nsow and (iv) exposure to playback of piglets\u2019 screams at 10 and 24 h after the onset of parturition. A sow was
\nscored as responsive if she changed her posture in response to the stimuli. The behavioral scores were
\nanalyzed during three predefined periods: parturition (from birth of first piglet to birth of last piglet), phase 1
\n(from birth of last piglet to 12 h after birth of first piglet) and phase 2 (from 12 h after birth of first piglet to
\n24 h after birth of first piglet). The responsiveness of sows towards humans during blood sampling differed
\nbetween the three periods ( p < 0.01), whereas it did not differ between periods during human handling of
\npiglets. During blood sampling, fewer sows were responsive during phase 1 (5%) compared to during
\nparturition (11%) and the later phase 2 (17%). We did not detect any temporal changes in sow responsiveness
\ntowards natural incidences of screaming of own trapped piglet between the three periods (it
\nremained high: 80%), whereas sows exposed to playback of piglet screams had a higher probability
\n( p < 0.05) to react at 12 h (50%) than at 24 h (25%). In conclusion, the responsiveness of sows toward direct
\nhuman contact was lower during the first 12 h postpartum. The careful handling of piglets in the home pen
\nhad a minimal effect on the probability of postural changes in sows. However, sows were highly reactive
\ntowards the screaming of own trapped piglet during the whole 24 h period pp. The relative lower responsiveness towards playbacks, decreasing from 12 to 24 h pp, cast doubt upon the piglet scream
\nplayback test as a useful approach to evaluate maternal responsiveness in sows.<\/p>\n