Published online by Cambridge University Press: 18 August 2016
The objective of this work was to evaluate the ultrasound method as a tool for in-vivo breast and abdominal fat prediction on Campero-INTA broilers. Breast length (mm), width (mm), surface (mm2; ultrasound) and depth (mm; ultrasound), and abdominal fat depth (mm; ultrasound) were measured at 65-66 and 72-73 days of age on 96 males. At 79 days of age, the broilers were weighed and slaughtered. Breast and abdominal fat weights (g) were obtained. Multiple regression equations were fitted using live weight (g) and in-vivo measurements to predict breast and abdominal fat weights and proportions (g/g). The best model for each case was selected by the Stepwise procedure. Equations fitted were verified using another set of data. Breast weight prediction using live weight and breast length in the model was as accurate as using live weight and breast depth. The former is recommended for breeding work. Abdominal fat weight prediction using ultrasound measurements of fat was less accurate than breast weight prediction. Repeatabilities for ultrasound breast measurements were higher (0·72 to 0·73) than those for abdominal fat (0·51 to 0·52). Operator effect may be important when training levels are different.