Real-time circadian changes in the behavioral activities of lactating Holstein Friesian and Simmental cows as recorded by an electronic ear sensor system

Abstract

ABSTRACT This study used the CowManager SensOor system to examine the behavioral circadian rhythms of 19 Holstein Friesian and Simmental dairy cows in a semi-open barn over 18 months, from October 1, 2020, to March 31, 2022. Over a cumulative total of 4560 days, the sensor system analyzed high active, active, not active, eating, and rumination behaviors of cows. High active, active, and eating behaviors peaked during daylight hours, while not active and rumination values increased during nighttime periods. Specifically, high active and active behaviors peaked in the morning (09:00-10:00h a.m.), while eating exhibited bimodal peaks in both the morning and evening (10:00h a.m. and 09:00h p.m.). Similarly, rumination values were relatively high in the early morning (05:00h a.m.), declined during the day, and peaked again in the evening (07:00h p.m.). In conclusion, this study reveals that lactating cows’ behavioral patterns, are influenced by circadian rhythms, seasonal changes, and lactation stages.