PSX-19 - Does housing pigs with access to a ramp alter pig behavior during the nursery period?

Abstract: Previous work by our group has found that housing pigs with a ramp in the pen during only the nursery period increased the speed of trailer ramp loading at marketing. However, the presence of the ramp may also alter pig behavior during the nursery period. The objective of this study was to evaluate whether ramp exposure affects pig behavior during the nursery period. We predicted that pigs exposed to a ramp would exhibit reduced aggressive behaviors, but similar eating, drinking, and postural behaviors during the nursery period compared to pigs not given access to a ramp. Two hundred four pigs (17 - 21 d of age) were placed in 8 pens (n = 24 – 27 pigs per pen) that were allocated to 1 of 2 treatments: 1) RAMP (n = 4 pens; standard commercial pen equipped with a ramp), or 2) CONTROL (n = 4 pens; standard commercial pen without a ramp). One day after placement (D1) and again 18 d later (D2), incidences of eating, drinking, aggressive, and postural (standing, lying) behaviors within each pen were collected for a period of 60 min at 0800, 1200, and 1600 h using a 5-min instantaneous scan sampling strategy. Data were analyzed using the GLIMMIX procedure in SAS with treatment, experimental day (D1, D2), hour (0800, 1200, 1600 h), and all 2-way interactions as fixed effects. Pen was included as a random effect. No treatment differences (P > 0.55) were detected for the evaluated behaviors. Greater incidences of eating were observed on D2 than on D1 (P < 0.0001). There were fewer pigs drinking at 1600 h on D1 than all other time points (P < 0.04) except for 1200 h on D1 (P = 0.64). There were also fewer pigs drinking at 1200 h on D1 than at 1600 h on D2 (P = 0.047). A greater incidence of aggressive behavior was observed at 0800 h on D1 compared to all other time points (P < 0.01), with no other differences observed (P > 0.40). Standing behavior was greater at 0800 h on D1 compared to all other time points (P < 0.02) except for 1600 h on D2 (P = 0.42). There were also fewer incidences of standing at 1600 h on D1 than 0800 or 1200 h on D2 (P = 0.01 and 0.03, respectively). Finally, there were more lying incidences at 1600 h on D1 than all other time points (P < 0.02) except for 1200 h on D1 (P = 0.81). Taken together, eating, drinking, aggressive, and postural behaviors changed by experimental day and hour after weaning. However, pig behavior was not altered due to ramp exposure.