Using air-blow and floor vibration to trigger posture changes in gestating and lactating sows

• Treatments with air-blow and floor vibration have been tested as actuators for sows.
• Eliminations or panic reactions have not been observed.
• Gestating sows showed a high reactivity of 80% on both stimulations.
• Untreated neighbouring sows showed no distinguishable reaction.
• The application as actuator requires adjustment to the individual reactivity level.

Recent approaches to minimise piglet crushing are usually active interventions in the behaviour of the piglets or the sow. However, interfering pig behaviour with the help of actuators has rarely been studied with respect to suitability, effectiveness and impact on animal welfare. In this study floor vibration and air-blows as methods to trigger posture changes have been tested on 12 sows in their late gestation and early lactation period. The intention was to quantify the effectiveness and unwanted side effects such as panic reactions as well as effects on neighbouring sows when applied in regular farrowing pens. The observed variables were reactivity, with reaction defined as posture change from lying to sitting, reaction latency and recline latency. In most cases, a reaction was achieved within 25 s and the arousal ceased in less than two minutes. In 22% of all stimulations the reaction latency was lower than 3 s, which could suggest an alarm reaction. The reactions of neighbouring sows could not be distinguished from natural occurring spontaneous posture changes and no low latency reactions were observed here. The sows in the late gestation phase showed a high reactivity on both actuators of about 80%. After farrowing, the reactivity was reduced to about 50% and nearly no low latency reactions could be observed. Hence, actuators need to be scalable to the individual reactivity level of the specific sow. This level is a complex variable that not only depends on the sow’s age and individuality but also on its antecedent and current state. The examined actuators can be dynamically adapted to the individual reactivity level. Together with a posture tracking system and a piglet stress monitoring system, such as the stress monitoring and documentation system STREMODO, this would allow an active piglet crushing intervention. With further research on the effect on piglets this technology might be usable with farrowing crates as well as in loose-housing farrowing systems.