A method and system of supplying rodents, such as mice, to medical researchers pre-installs and/or embeds physiologic sensors onto or within the rodents prior to selling the modified rodents to the researchers. The specialty skills, such as small animal surgical and anesthesia skills and sensor placement and testing, are centralized in one organization rather than being spread about a collection of researchers. The subjects with preinstalled, pre-tested hardware, are sold to the researcher as needed. Communication hardware and software will be supplied for the user to convert their desktop computer into a wireless monitoring station. Additionally an external pulse oximeter for small rodents, such as mice, provides measurements on a hand or foot of the rodent with a sensor configured to avoid shunting around the rodent appendage, and configured for high heart rates (200-900 beats per minutes) of the subjects.