SLOVENIAN VETERINARY RESEARCH

C curve (AUC) for the criterion value of 120 days post partum (AUCndicates that FPR is valuable in distinguishing cows with different CC62O. Podpečan, J. Mrkun, P. Zrimšek10,90,80,71,00,90,8optimal cut off value1.22 1.37 1.53sensitivity0,60,50,40,30,2validity estimate0,70,60,50,40,30,2sensitivityspecificity0,10,100 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 11 - specificityFigure 2: ROC curve of FPR for identifying healthy cowswith pre-selected minimum of postpartum period atve of FPR for identifying healthy cows with pre-selected minimum of120 days120 days Characteristics for the ROC curve are as follows: Areae ROC under curve the are curve as (AUC): follows: 0.726, P Area < 0.0001 under the curve (AUC): 0.726, P 1.37with 71 % accuracy, at ant of FPR = 1.37, corresponding to a sensitivity of 74 % and specificity0,80,8sitivity was found for the cut-off at 1.22, whereas cut-off at 1.53pecificity of FPR (Fig. 3).0,60,6stic parameters of FPR according to pregnancy status at 120 days postion of optimal cut-off valuesproportion of cows non pregnant1,00,40,2ASurvival Analysishealthy cows with FPR < 1.37optimal cut-off value0,00,0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1,0 1,1 1,2 1,3 1,4 1,5 1,6 1,7 1,8 1,9 2,0FPRFigure 3: Plot of diagnostic parameters of FPR accordingto pregnancy status at 120 days post partum for theselection of optimal cut-off valuesproportion of cows non pregnant0,40,2BSurvival Analysiscows with clinical ketosis; FPR < 1.37cows with clinical ketosis; FPR > 1.37validity estimate1,00,90,80,70,60,50,40,30,20,10,0proportion of cows non pregnant1.22 1.37 1.530,00,00 50 100 150 200 250days after calvingC1,0sensitivityspecificity0,80,60,4Survival AnalysisSurvival Analysiscows with fertility problems; FPR < 1,37cows with mastitis; FPR < 1.37cows with fertiliy problems; FPR > 1,37Dcows with mastitis; FPR > 1.370,0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1,0 1,1 1,2 1,3 1,4 1,5 1,6 1,7 1,8 1,9 2,00,2FPRproportion of cows not pregnant1,00,80,60,40,20 50 100 150 200 250 300 350days after calvingprotein ratio 0,00 50 100 150 200 250 300 350days after calvingaccording to FPR in healthy cows and cows with ketosis, fertilitymastitis0,00 50 100 150 200 250 300 350days after calvingFigure 4: Kaplan-Meier survival analysis for the proportion of cows clinically healthy cows (A), cows with clinicalketosis (B), cows with fertility problems (C) and cows with clinical mastitis (D) non pregnant, according to the cutoff value of FPR at 1.377