Monitoring vital signs and activities in pig pens during the farrowing period is crucial for reducing pre-weaning piglet mortality and enhancing farm productivity. Traditional methods focus on either vital signs or activities separately, falling short in the dynamically changing farm environment. This paper introduces a multiscale vibration sensing method which dynamically adjusts sensor amplifier gain to detect both vital signs (e.g. heartbeats and respirations) and larger-scale activities (e.g. walking, eating, nursing, etc.). Preliminary trials demonstrate the system's potential to adapt to rapidly changing conditions by switching between high sensitivity for vital signs and reduced sensitivity for activity sensing depending on the detected vibration signal.