Predicting live and carcass lean using bioelectrical impedance technology in pigs

Bioelectrical impedance technology was used to evaluate 36 pigs (103 +/- 1. 5 kg) and their cold carcasses (75.5 +/- 1.9 kg) with a four-terminal pleth ysmograph. Pigs were transported to the abattoir, weighed, and live impedan ce measurements recorded. The whole carcass and right side were weighed and cold carcass resistance and reactance measurements were obtained on the ri ght half. Length (cm) was measured as the distance between the detector ter minals, The right carcass half was separated into lean, fat, bone, skin and inseparable (inseparable lean and fat) portions and individually weighed. Lean and inseparable components were each ground three times and two sample s from each component were collected and stored at - 20 degrees C until ana lyzed. The right carcass sides averaged 38.2 kg (S.D. = 1.1). Live and carc ass resistance, reactance, and lengths were 38 Omega, 5.4 Omega, 87.5 cm, a nd 221 Omega, 60 Omega, 76 cm, respectively. Total carcass lean and percent lean averaged 40 kg and 53%, respectively. Carcass impedance measurements (weight, resistance, carcass reactance, and carcass length) accounted for 8 8.4% of the variation with a RMSE = 1.26 kg for total carcass lean. However , live resistance, reactance and length explained only 62.6% of the variati on (RMSE = 2.04 kg) of the total carcass lean. Bioelectrical impedance has potential as a robotized procedure in an online system in a commercial plan t with a minimum of perturbation for estimation of total lean of pork carca sses. (C) 1999 Elsevier Science B.V. All Fights reserved.