A comparison of different pre and post-slaughter measurements for estimating fat reserves in Spanish Blanca Celtibérica goats

Abstract

Five pre-slaughter measurement values and four post-slaughter measurement values were used to estimate the weight of fat in the omental (OM), mesenteric (MES), perirenal (PR), subcutaneous (SC), and intermuscular (IM) fat depots in goats. The pre-slaughter measurements were: live weight (LW), sternal body condition score (BCSs), lumbar body condition score (BCSl), sternal fat thickness (FTs) and lumbar fat thickness (FTl) measured by ultrasound. The post-slaughter measurements were empty live weight (ELW), hot carcass weight (HCW), adipocyte diameter in the sternal subcutaneous fat (ADSCs) and adipocyte diameter in the lumbar subcutaneous fat (ADSCl). Linear and multiple regressions were fit to data collected from 22 adult, non-pregnant and non-lactating Blanca Celtibérica does. The results obtained showed BCSs, ranging from 1.5 to 4.5 (scale: 0-5) to be the best pre-slaughter estimator of an animal's total fat (R2 = 0.90, RSD = 2.252 kg) and HCW to be the best post-slaughter estimator (R2 = 0.92, RSD = 1.972 kg). Additionally, multiple regression using HCW and ADSCl together yielded estimates of the total amount of fat in all five of the depots considered here with an R2 = 0.95 and an RSD = 1.542 kg. Therefore, the use in vivo of BCSs is the best method for predicting nutritional status in does in extensive production systems in the Mediterranean region.Key words: Fat reserve, body weight, carcass weight, body condition score, ultrasound, adipocyte, goat