Is calving-monitoring technology useful?

Can technologies like locomotion detectors and rumination monitors accurately predict calving time and thus improve calving outcomes?

A team of researchers from Canada and Germany recently conducted a trial to explore this possibility. Their study, published in the Journal of Dairy Science, evaluated four factors as indicators of the onset of calving:

(1)

Vaginal temperature - Measured via a vaginal temperature logger that recorded temperature at 1-minute intervals.

(2)

Rumination - Recorded every hour via an ear-attached sensor.

(3)

Lying time - Monitored with a leg-attached accelerometer that recorded cow position at 1-minute intervals.

(4)

Lying bouts - Measured with the same accelerometer

Forty-two cows in a commercial Quebec dairy herd were fitted with the technology approximately one week before their expected calving date. The data was analyzed for accuracy of calving prediction in the next 24, 12 and 6 hours. Among the study's findings:

• A decrease in vaginal temperature of >0.1ÀöC was the single more accurate predictor of calving within the next 24 hours.
• A combination of all three technologies and all four metrics yielded the most accurate results in predicting calving within the next 24 hours.
• The time period of significant change varied among the monitored factors. The most significant temperature drop occurred during an average of 12 to 18 hours before calving. Lying time reached a minimum at 6 to 12 hours before calving. Rumination reached its lowest point, and lying bouts reached their highest point, in the last 6 hours before calving.

The authors concluded that, although even the combination of all technologies and factors could not precisely predict the exact time of calving, the information was helpful in predicting the imminence of calving in the next 24, 12 and 6 hours. This information could be helpful in moving animals to calving facilities; preventing overcrowding of calving facilities; and more closely monitoring close-up animals to provide calving assistance, if needed, and immediately tend to newborns.

The researchers noted such monitoring would be most helpful for managers of large herds to provide individual-cow care. Two of the three devices used to record behaviors in the study would not be practical in a commercial setting because they required manual data downloading. However, commercial technologies likely have the capability of measuring calving indicator metrics, either currently or in the near future.

Finally, the authors pointed out the animal-welfare benefits of accurate calving detection. The awareness of calving allows for less pain and distress during difficult calving, plus more attentive newborn care for all calvings.