Knowing when a cow is about to give birth can make a real difference in dairy farm management. Timely calving detection helps farmers prepare for delivery, monitor animals more effectively, and provide assistance when needed. However, because calving can happen at any time of the day or night, identifying the right moment remains a challenge.
wiCow addresses this challenge through sensor-based monitoring. A poster abstract published in Reproduction in Domestic Animals, a Wiley journal, evaluated two wiCow alerts: an early warning based on a drop in vaginal temperature, and an imminent-calving alarm triggered by expulsion of the device as the calf entered the birth canal.
The findings provide useful insight into how these two alerts can support calving monitoring in dairy cows and heifers.
How Does wiCow Work?
In the study, wiCow used two signals associated with the calving process:
- First alarm — Early warning: A 0.5°C drop in vaginal temperature triggered the first alarm, indicating that calving might be approaching.
- Second alarm — Imminent calving: The second alarm was triggered when the device was expelled through the vulva as the calf entered the birth canal.
These alerts provide complementary information: an earlier signal to support preparation, followed by a more immediate indication of progression toward delivery.
What Does the Scientific Research Tell Us?
The study enrolled 68 Holstein-Friesian animals: 45 cows and 23 heifers. wiCow was inserted intravaginally approximately 10 days before the estimated calving date.
The researchers defined an alarm rate as the number of animals that triggered the alarm divided by the number of animals with the device in the relevant analysis. The combined results for cows and heifers were:
| Monitoring result | Alarm rate |
|---|---|
| First alarm — cows and heifers combined | 93.33% (56/60) |
| Second alarm — cows and heifers combined | 97.06% (66/68) |
The first-alarm analysis included 60 animals, while the second-alarm analysis included 68. The abstract does not explain the difference between these analysis denominators. These figures describe reported alarm rates, rather than an overall diagnostic accuracy measure.
From Early Warning to Imminent Calving
One of the most notable findings was the interval between the alarms and actual delivery.
On average, the first alarm occurred approximately 16.7 hours before delivery. The reported combined mean was 1,003.74 ± 65.97 minutes, giving farmers time to prepare and increase their attention to the animal.
The second alarm occurred much closer to birth, with a reported combined mean of 9.91 ± 2.75 minutes before delivery — approximately 9.9 minutes.
The reported values are group averages with standard errors of the mean, not guaranteed warning times for an individual animal. Together, the two alerts offer an earlier warning to support preparation and a more immediate signal that delivery is approaching.
Why Does This Matter for Dairy Farmers?
Calving alerts can help farmers plan their workload, prioritize animal monitoring, and respond more efficiently when a cow is approaching delivery.
For farms managing multiple animals, technology-assisted monitoring can be particularly valuable when calving occurs overnight or outside regular working hours.
The temperature-based early warning and the expulsion-triggered alarm studied here offer information at different stages of the calving process. This approach supports the goal of making monitoring more proactive and helping farmers make better-informed management decisions.
As with any monitoring technology, alerts should complement appropriate animal observation and veterinary assistance when complications arise.
Science and Technology Working Together
The poster abstract reported high alarm rates for both alerts in the animals evaluated. Its findings support the potential of wiCow to help detect the approach of delivery in dairy cows and heifers. The sample size and the different analysis denominators should be considered when interpreting the results.
By bringing sensor-based monitoring and timely alerts together, wiCow aims to help dairy farmers better anticipate calving and manage this important stage of the production cycle.
At wiCow, our goal is to make calving monitoring smarter, more practical, and more responsive to the needs of modern dairy farming.
Discover wiCow and our approach to calving detection.
Scientific Reference
Ergun, Y.; Tatar, G.; Kaya, U.; Gozer, A.; Polat, C.; Cirak, T. P6: The efficacy of a sensor-based device (WiCow) placed intravaginally on estimation of the delivery time in the dairy cows and heifers. Reproduction in Domestic Animals (Wiley), 2026; 61(Suppl. 2):e70276, poster abstract P6, p. 6 of the poster collection.
Read the wiCow research abstract — P6 (PDF, page 6)
The wiCow abstract is on page 6, under P6. If Wiley’s viewer opens at the beginning, select page 6 in the PDF viewer.