Predicting farrowing of sows housed in crates and pens using accelerometers and CUSUM charts

The model detected a rise in activity on average 13 ± 4.8 h (mean ± standard deviation) before farrowing in sows housed in crates and pens with sensitivity of 96.7% and specificity of 100%. The fact that we were able to use a single model with a constant set of parameters gives indication that the method has potential to become a robust indicator of farrowing in different housing systems, even though pre-farrowing activity was higher in sows housed in pens than in crates.