Ramezani Gardaloud, Nasrin (University of Veterinary Medicine Vienna / Smartbow GmbH) Nasrin Ramezani Gardaloud Klein-Jöbstl, Daniela (University of Veterinary Medicine Vienna) Daniela Klein-Jöbstl Drillich, Marc (University of Veterinary Medicine Vienna) Marc Drillich Iwersen, Michael (University of Veterinary Medicine Vienna) Michael Iwersen Auer, Wolfgang (Smartbow GmbH) Wolfgang Auer Öhlschuster, Manfred (Smartbow GmbH) Manfred Öhlschuster Kickinger, Florian (Smartbow GmbH) Florian Kickinger Steininger, Alexandra (Smartbow GmbH) Alexandra Steininger Lidauer, Laura (Smartbow GmbH) Laura Lidauer Guse, Christian (University of Veterinary Medicine Vienna) Christian Guse MDPI 2022 Accelerometers (ACL) can identify behavioral and activity changes in calves. In the present study, we examined the association between bovine respiratory disease (BRD) and behavioral changes detected by an ear-tag based ACL system in weaned dairy calves. Accelerometer data were analyzed from 7 d before to 1 d after clinical diagnosis of BRD. All calves in the study (n = 508) were checked daily by an adapted University of Wisconsin Calf Scoring System. Calves with a score ≥ 4 and fever for at least two consecutive days were categorized as diseased (DIS). The day of clinical diagnosis of BRD was defined as d 0. The data analysis showed a significant difference in high active times between DIS and healthy control calves (CON), with CON showing more high active times on every day, except d -3. Diseased calves showed significantly more inactive times on d -4, -2, and 0, as well as longer lying times on d -5, -2, and +1. These results indicate the potential of the ACL to detect BRD prior to a clinical diagnosis in group-housed calves. Furthermore, in this study, we described the 'normal' behavior in 428 clinically healthy weaned dairy calves obtained by the ACL system. PDFDocument en 2023-08-01T09:25:57.461Z Dairy Heifer Calves; Technical-Note Evaluation; Feeding-Behavior; Automated Detection; Early Indicators; Mortality; Cattle; Rumination; System; Health 918247 b application/pdf CC BY 4.0 International