Estimating the energy partitioning of Taiwanese native chickens by mathematical model

The objective of the current study was to estimate the parameters needed to describe the energy partitioning of male and female Taiwanese native chickens (TNC) from 0 to 16 weeks by a mathematical model. One hundred and twenty-five 1-day-old, four-way crossbred male and female TNC (Taishu Meat No. 13) in Group 1 were divided into five pens with 25 chicks each, respectively. One chicken from each pen nearest to the mean body weight was selected weekly, slaughtered and their body and feather energy contents measured. Another 50 1-day-old males and 50 females were allotted to Group 2 and divided into two pens with 25 chicks each, respectively. Their body weight and daily metabolizable energy intake (DMEI) were measured weekly.The Mixed Gompertz model of body and feather energy deposition of chicks in Group 1 was used to estimate the parameter of daily metabolizable energy for body growth (DMEbg) and for feather growth (DMEfg). The daily ME for maintenance (DMEm) was calculated by the difference between DMEI and DMEbg + DMEfg.The parameters of the partitioning of DMEI to DMEbg, DMEfg and DMEm of TNC were estimated and the gender effects were compared. Males tended to have higher DMEI and spend it more on maintenance and less on body deposition as they approached sexual maturity. The opposite was true for females for depositing body energy for preparing for onset of lay.