Comparison of the energy utilisation of conventional and Taiwanese native male broilers

The objective of this study was to compare energy utilisation of conventional (CON; Arbor Acres) and Taiwanese native (NAT) male broilers. Sixty CON and sixty NAT broiler males were randomly assigned to five treatments. Each treatment consisted of four replicates of three chicks each. The chicks were fed five different levels (ad libitum or restricted to 85%, 70%, 55% and 40% of their respective ad libitum-fed group) of a common basal diet based on maize and soybean meal for three weeks. Apparent metabolisable energy (AME) intake, nitrogen-corrected apparent metabolisability of gross energy (q), energy, fat and protein retention, heat production and gross AME efficiency (kgross) were measured. Maintenance ME (MEm), AME efficiency for growth (kg), fat (kf) and protein (kp) gain were estimated by appropriate linear and multiple regressions.The results indicate that CON birds had higher AME intake, q, kg and kp, but similar MEm and kf than NAT birds. The increased AMEI caused by the higher FI and higher q contributed approximately to 60% of the higher kgross observed in ad libitum-fed CON birds as compared with ad libitum-fed NAT birds. The remaining 40% resulted from the higher kg caused by the higher fat to protein gain ratio and the higher kp of the CON birds.