o:1925 Early Detection of Respiratory Diseases in Calves by Use of an Ear-Attached Accelerometer en 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. Dairy Heifer Calves; Technical-Note Evaluation; Feeding-Behavior; Automated Detection; Early Indicators; Mortality; Cattle; Rumination; System; Health 1552099 10.3390/ani12091093 2023-08-01T09:25:57.461Z 44 yes 46 Nasrin Ramezani Gardaloud University of Veterinary Medicine Vienna / Smartbow GmbH Christian Guse University of Veterinary Medicine Vienna person 0000-0002-0120-019X Laura Lidauer Smartbow GmbH person Alexandra Steininger Smartbow GmbH person Florian Kickinger Smartbow GmbH person Manfred Öhlschuster Smartbow GmbH person Wolfgang Auer Smartbow GmbH person Michael Iwersen University of Veterinary Medicine Vienna person 0000-0001-7893-6050 Marc Drillich University of Veterinary Medicine Vienna person 0000-0002-2824-8185 Daniela Klein-Jöbstl University of Veterinary Medicine Vienna person 0000-0001-5806-7601 application/pdf 918247 https://phaidra.vetmeduni.ac.at/o:1925 no yes 16 70 1552253 Animals 13 12 9 MDPI 2022