Comparison of Fast and Medium-Growing Broiler Genotypes Raised Indoors: Growth Performance, Slaughter Results and Carcass Parts

Abstract

The aim of this research was to compare fast (Ross 308) and medium-growing (Hubbard ISA Red JA) broilers for growth performance and slaughter results under indoor conditions. In total 560 chicks from Fast (FG) and Medium-Growing (MG) genotypes were housed in 16 floor pens (1 2 chicks m(-2)). Feed and water were offered ad libitum and the lighting period was 18 h day(-2) after the first week. All birds were fed with starter diet (21.9% CP, 3020 kcal ME kg(-1)) for the first 3 weeks and then grower diet (19.5% CF. 3127 kcal ME kg(-1)) was used. Death, body weight and feed consumption were recorded. Chickens were slaughtered at 56 days of age. Slaughter losses, carcass, giblets, abdominal fat and carcass parts weight were determined. Sensory characteristics of whole raw carcasses were evaluated by 5 panellists with a 7-point scale. Mortality rates were compared by the Mann Whitney-U test and the others with the t-test. FGs had higher body weight gain and feed consumption than MGs during the fattening period (p<0.001). Mortality of MGs (2.78%) and FGs (2.43%) were similar. MGs showed higher head, feet + shanks, offal, giblets and fat pad percent (p<0.05). Hot carcass yields were 75.7 and 72.8% for FG and MG (p<0.001). FGs took higher values for raw carcass sensory traits as conformation, subcutaneous fatness and surface colour (p<0.05). Breast and breast meat yield were higher in FGs, however MGs showed higher means for legs, wings, neck and back percent. Taking into account the performance and slaughter results, MGs are disadvantaged compared to FGs.