Influence of environmental stimuli on nursing and suckling behaviour in domestic sows and piglets

The influence of environmental stimuli considered biologically relevant for nest building sows, on nursing and stickling behaviour and piglet growth w as investigated. Effects of floor type (beach sand v. concrete) and substra te type (straw feeder v. no straw feeder) were examined in a 2 X 2 factoria l experiment with nine replicates of four multiparous sows. The sows were k ept individually in roofed 7.6 m(2) 'get-away-pens' from 1 week pre-partum until 13 to 15 days post partum. The behaviour of sows and piglets were vid eo recorded for 24 h on days 0, 3, 6 and 12 post partum. The latency from termination of farrowing until perceptible milk ejection t ended to be shorter for experienced sows (parity 4 to 5) kept on sand than on concrete floors (1207 (s.e. 109) min; no. = 7 v. 1725 (s.e. 123) min; no . = 6, respectively. F-2,F-8 = 3.93, P < 0.07) and for experienced sows wit h access to a straw feeder than without access to a straw feeder (1257 (s.e . 113) min; no. = 8 v. 1666 (s.e. 132) min; no. = 5, respectively; F-2,F-8 = 3.56, P < 0.08). On days 3 and 6 a longer duration of suckling was found for sows on sand v. concrete floors (384 (s.e. 20) v. 327 (s.e. 16) s on da y 3; F-1,F-19 = 5.6, P < 0.03 and 377 (s.e. 14) v. 318 (s.e. 13) on day 6; F-1,F-21 = 9.09; P < 0.01, respectively) and with straw feeder v. without s traw feeder (385 (s.e. 20) v. 326 (s.e. 18) s on day 3; F-1,F-19 = 5.11, P < 0.04 and 372 (s.e. 14) v. 323 (s.e. 13) on day 6; F-1,F-21 = 6.21; P < 0. 03, respectively). On day 3, a tendency for a sand X straw feeder interacti on (F-1,F-18 = 3.58, P<0.08), showed that sows without environmental stimul i terminated more sucklings than sows with access to a straw feeder and sow s kept on sand (32 (s.e. 7) %, 16 (s.e. 4) % and 13 (s.e. 5) %, respectivel y). Similarly, on day 6 a significant sand X straw feeder interaction (F-3, F-16 = 7.15, P < 0.01) led to increased frequency of foreleg rowing for sow s without environmental stimuli compared with the three other treatments (1 4 (s.e. 2) v. 7 (s.e. 1), 5 (s.e. 1) and 6 (s.e. 1) foreleg rowings per h, respectively). During the stay in the experimental pens, the growth rate of piglets kept on sand tended to be higher than for piglets kept on concrete floors (261 (s.e. 33) v. 240 (s.e. 30) g per piglet per day; F-1,F-25 = 3. 38; P < 0.08). The results of the present experiment indicate that provision of biological ly relevant stimuli affect the nursing and suckling behaviour of sows and p iglets. The reduced termination of sucklings, the reduced frequency of fore leg rowing, the increased duration of suckling as well as the earlier devel opment of suckling behaviour might have been advantageous for the early mil k intake of the piglets.