The allometric partition of whole body protein in lean fraction of growing pigs using information from three different datasets

The hypothesis that a single allometric relationship relating carcass lean protein (CLP) to whole body protein (WBP) can allow accurate estimates of CLP on pigs of different populations, sex and nutritional history, was tested. Three datasets of different origins were used. Data were representative of 548 pigs, castrated males and females, of 8 pig populations, serially slaughtered over ample empty body weight (EBW) ranges (from 22 to 217 kg). WBP and CLP ranged, respectively, from 2 to 28 and from 1 to 16 kg. The pooled data were run and the following relationship was found: CLP=0.497*WBP1.021 (CV=0.062; rsd=0.501 kg). The residuals were subjected to ANOVA to test the effects due to dataset, pig population within dataset and sex; significant differences between datasets mean residuals (+0.095, SE=0.041; -0.258, SE=0.094; -0.116, SE=0.055 kg, P < 0.001) were observed. No differences due to sex and pig populations were found. The average residuals were low and only in few cases they differed from zero. Conclusions: CLP can be accurately predicted from WBP; the coefficients of this function are mainly influenced by the procedures of slaughtering, dissection, sampling and analysis.