caa a22 4500 388062819 CHVBK 20180307125126.0 cr unu---uuuuu 161130e199802 xx s 000 0 eng 10.1079/BJN19980028 doi S0007114598000294 pii (NATIONALLICENCE)cambridge-10.1079/BJN19980028 Prediction of the chemical composition of lamb carcasses from multi-frequency impedance data [Elektronische Daten] Multi-frequency bioimpedance analysis (MFBIA) was used to determine the impedance, reactance and resistance of 103 lamb carcasses (17·1-34·2 kg) immediately after slaughter and evisceration. Carcasses were halved, frozen and one half subsequently homogenized and analysed for water, crude protein and fat content. Three measures of carcass length were obtained. Diagonal length between the electrodes (right side biceps femoris to left side of neck) explained a greater proportion of the variance in water mass than did estimates of spinal length and was selected for use in the index L2/Z to predict the mass of chemical components in the carcass. Use of impedance (Z) measured at the characteristic frequency (Zc) instead of 50 kHz (Z50) did not improve the power of the model to predict the mass of water, protein or fat in the carcass. While L2/Z50 explained a significant proportion of variation in the masses of body water (r2 0·64), protein (r2 0.34) and fat (r20·35), its inclusion in multi-variate indices offered small or no increases in predictive capacity when hot carcass weight (HCW) and a measure of rib fat-depth (GR) were present in the model. Optimized equations were able to account for 65-90% of the variance observed in the weight of chemical components in the carcass. It is concluded that single frequency impedance data do not provide better prediction of carcass composition than can be obtained from measures of HCW and GR. Indices of intracellular water mass derived from impedance at zero frequency and the characteristic frequency explained a similar proportion of the variance in carcass protein mass as did the index L2/Z50. Copyright © The Nutrition Society 1998 Carcass composition nationallicence Bioelectrical impedance nationallicence Lamb nationallicence Hegarty R. S. Elizabeth Macarthur Agricultural Institute, Camden, NSW 2570, Australia McPhee M. J. NSW Agriculture Beef Centre, University of New England, Armidale, NSW 2351, Australia Oddy V. H. Cattle and Beef Industries Cooperative Research Centre, University of New England, Armidale, NSW 2351, Australia Thomas B. J. Centre for Medical and Health Physics, Queensland University of Technology, Brisbane 4001, Australia Ward L. C. Department of Biochemistry, University of Queensland, Brisbane 4072, Australia British Journal of Nutrition Cambridge University Press 79/2(1998-02), 169-176 0007-1145 79:2<169 1998 79 BJN https://doi.org/10.1079/BJN19980028 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1079/BJN19980028 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Hegarty R. S. Elizabeth Macarthur Agricultural Institute, Camden, NSW 2570, Australia NATIONALLICENCE 700 1- McPhee M. J. NSW Agriculture Beef Centre, University of New England, Armidale, NSW 2351, Australia NATIONALLICENCE 700 1- Oddy V. H. Cattle and Beef Industries Cooperative Research Centre, University of New England, Armidale, NSW 2351, Australia NATIONALLICENCE 700 1- Thomas B. J. Centre for Medical and Health Physics, Queensland University of Technology, Brisbane 4001, Australia NATIONALLICENCE 700 1- Ward L. C. Department of Biochemistry, University of Queensland, Brisbane 4072, Australia NATIONALLICENCE 773 0- British Journal of Nutrition Cambridge University Press 79/2(1998-02), 169-176 0007-1145 79:2<169 1998 79 BJN CC0 http://creativecommons.org/publicdomain/zero/1.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-cambridge