Fig 1.
Schematic representation of the experimental procedure per study group.
Accelerometers and noseband sensors (RumiWatch-units = RWU) are either attached (light grey) or attached and data recorded (dark grey). Video recording (VR) procedures used for habituation of study cows to the procedure are marked in light grey, VR used for lameness assessment are marked in dark grey. AS = Animal Selection, CE = clinical examination, AO = animal observation (heat, illness, gait scoring), FE = foot examination in the trimming chute.
Table 1.
Variables of RumiWatch noseband sensors and 3D-accelerometers (RumiWatch, ITIN+HOCH GmbH, Fütterungstechnik, Liestal, Switzerland).
Table 2.
Clinical variables of non-lame (group C) and lame (group L) cows.
Table 3.
Variables of RumiWatch noseband sensors and accelerometers (RumiWatch, ITIN+HOCH GmbH, Fütterungstechnik, Liestal, Switzerland) of non-lame (group C) and lame cows (group L).
Fig 2.
Box Plot representations of number of standing bouts (A) and walking speedcalc (B) of group C (NRS ≤ 2), group LI (NRS = 2.5–3), group LII (NRS = 3.5) and group LIII (NRS ≥ 4). Different characters (a, b, c) indicate a significant difference (P < 0.05). Numerical rating system (NRS) is according to Flower and Weary [38].
Fig 3.
Receiver operating characteristics (ROC) curves of different logistic regression models to discriminate between lame (NRS ≥ 2.5) and non-lame cows (NRS ≤ 2).
First model (-∙-) includes standing bouts (AUC = 0.81), second model (─) includes walking speedcalc (AUC = 0.88); third model (- -) includes walking speedcalc and the number of standing bouts (AUC = 0.96); fourth model (∙∙∙) includes walking speedcalc, the number of standing bouts and the eating time (AUC = 0.96). NRS = numerical rating system according to Flower and Weary [38]. AUC = area under the receiver operating characteristics curve.
Table 4.
Results of univariable logistic regression and receiver operating characteristics analysis of a cow being lame (numerical rating system according to Flower and Weary [38], NRS ≥ 2.5) using different RumiWatch noseband sensor and accelerometer (RumiWatch, ITIN+HOCH GmbH, Fütterungstechnik, Liestal, Switzerland) variables as predictors on the cutoff value with highest sensitivity + specificity.
Table 5.
Using different RumiWatch noseband sensor and accelerometer (RumiWatch, ITIN+HOCH GmbH, Fütterungstechnik, Liestal, Switzerland) variable combinations as predictors of a cow being lame (numerical rating system according to Flower and Weary[38], NRS ≥ 2.5) in multivariable logistic regression and receiver operating characteristics analysis on different cutoff-values with corresponding sensitivity and specificity.