N. D. HOAN, T. Q. HIEN and T. T. HOAN
Thai Nguyen University, Thai Nguyen province, Vietnam
Hoan, N. D., T. Q. Hien and T. T. Hoan, 2016. Egg production performance of the local RI hen and its crossbreeds with ISA-brown strain in semi-intensive conditions. Bulg. J. Agric. Sci., 22 (Suppl. 1): 87–91
A cross between the ISA-Brown industrial strain and Vietnamese local (Ri) breed was compared with the Vietnamese local (Ri) hen. The comparison during the egg production period was done in individual cages, in a ventilated henhouse without any particular isolation. The same commercial diet has been provided over three time periods (35 to 36 weeks, 50 to 51 weeks and 65 to 66 weeks of age). Egg number and body weight at first egg was significantly lower in the Ri local breed. Mortality was almost equal during the breeding and the egg production periods for the two genotypes. The Ri hen eggs, in spite of a lower weight (43.70 to 53.37 g respectively at the same age), gave yolk to albumen ratio similar to that of the ISARI cross (0.52 to 0.58 g respectively at the same age). Finally, the ISARI cross was better in terms of egg production and egg quality than the local hen, in the test conditions.