© Lars Haugaard, Aarhus University, Denmark
Vaginal Implant (VIT)
Birth detection: When the VIT is pushed out of the mother’s body, two things are expected to happen: the temperature around the VIT will most likely drop and the motions will stop. When this happens, the VIT will send a birth event message to the VERTEX Plus collar which will conduct an unscheduled GPS fix and send an alert notification to the researcher (if the collar is equipped with a remote communication option).
Separation: The VIT continuously transmits an ID code on a UHF frequency to the mother’s VERTEX Plus collar. When the mother moves away from the calving site, the ID signal is not received any longer. The VERTEX Plus collar will send a separation message after one hour has passed without detecting the ID signal.
Localisation: To locate the calving site, the VIT is equipped with a VHF beacon transmitter. The VHF can be programmed as flexible as the one in the GPS collar.

Vaginal Implant (VIT)
Applications
- Reproduction: Find the calving site and observe the time directly after birth. How long does the mother stay close to the calving site?
- Reproduction 2: Collar the offspring and observe the mother – offspring behaviour and development of the calf.
- Physiological data: Combine GPS, activity and the detailed temperature values of the VIT and get a fine scaled picture of the pregnancy.