Relationships between chemical composition and physically separated tissues of the pig carcass

Data from the physical and chemical dissection analysis of 50 Large White and 50 Hampshire × Large White carcasses, comprising equal numbers of gilts and castrates, slaughtered at 90 kg liveweight, are presented. The right-hand side of each carcass was dissected into lean, fat and bone and the combined tissues were then minced and chemically analysed for moisture, protein, ether extract and ash. Statistical relationships between the two methods of carcass analysis, except those between bone and ash, were not influenced by sex or breed type. Overall regression equations, i.e. ignoring sex and breed type, for the prediction of percentage lean from moisture, protein and ether extract percentages of the carcasses, had residual standard deviations of 1·26, 1·78 and 1·11, respectively, and corresponding values for the prediction of percentage carcass fat were 1·05, 1·68 and 0·74. Residual standard deviations for predicting percentages of moisture and protein in the carcass from percentage lean content were 1·07 and 0·46 and that for the prediction of percentage ether extract from fat percentage of the carcass was 1·20. Corresponding relationships between bone and ash percentages of the carcass were less satisfactory for predictive purposes.