Corrections To Prediction Of Backfat Thickness And Relationships Among Model Parameters In Inraporc®

Abstract

We evaluated whether the procedure for correcting backfat thickness (BT)equation coefficients and lipid mass (LM) initial values in animal profiles, as well asactual model parameter (MP) data and their interrelationships, could reduce errors inpredicting body weight (BW) and BT in pigs reared in Southern Brazil. Because differentcombinations of actual and estimated MP values in advanced system calibration mode(ACM) give rise to distinct calibration procedures, their BT and BW prediction errorswere compared with those obtained by INRAPORC® default mode calibration basedon different parameter combinations. Correlations among MP were also verified. TheBT prediction correction (BTcor) procedure reduced the BT standard deviation of theestimate (σ) from 3.25 to 2.42 mm, but the correction had no effect on BW. Actual BTand feed intake data at 50 kg BW (FI50), reported in ACM, reduced prediction errorsof BW and BT, in which their σ values were reduced from 5.29 to <4.08 kg and 2.42 to<2.12 mm, respectively. Mean protein deposition (MeanPD), FI50, and feed intake at100 kg BW (FI100) were strongly and positively correlated (r>0.98). In addition, initialBW (BWi) was strongly negatively correlated with these parameters (r