A study on the growth performance and feed consumption of six dual-purpose genotypes chicks reared under the free-range management system was conducted during the period 2014–2015 in the poultry farm at the Agricultural University in Plovdiv as follows – Tetra H and Tetra SH hybrids, White Plymouth Rock breed (line L), Barred Plymouth Rock breed (line E) Bielefelder breed and Australorp breed. TheTetra H hybrid was of the highest live body weight of 2,901±59 g in 2014 and 3,040±96 g in 2015 respectively, while Bielefelder breed was of the lowest live body weight of 1,952±71 g in 2014 and 1,796±20 g in 2015 respectively. During the experimental period feed consumption varied as follows: from 2.02 kg/kg (feed/body weight) for Tetra H hybrid to 3.70 kg/kg for Bielefelder breed from hatching to 21st day of age; from 2.05 kg/kg for Tetra SH hybrid to 2.89 kg/kg for White Plymouth Rock breed from 22nd to 56th day of age, and from 5.03 kg/kg for Barried Plymouth Rock breed to 8.22 kg/kg for the Tetra H hybrid from 57th to 133rd day of age. During the whole experimental period the mortality rate of 0% to 7.52 % was considered to be relatively low.
Comparative study on the growth performance of different chicken genotypes in a free-range management system