A trial was carried out to evaluate the growth and performance of naked neck birds. Four hundred birds were distributed into four treatments in factorial arrangement (2 strains x 2 genders), with five replicates of 20 birds each. The naked neck strains evaluated were Sasso and ISA Label. The birds were fed a diet formulated with corn and soybean meal according to the nutritional requirements. Food intake, body weight gain and food conversion were determined at 28, 56, and 84 days as well as the yield of carcass and cuts at 84 days. No interaction was observed between gender and strain (P>0.05). Food intake and body weight gain were different (P <0.05) between the strains and between the genders. Sasso strain presented higher performance than ISA Label. The parameters estimated for Gompertz equation, the weigh at maturity (Wm) and time that the growth rate is maximum (t*) were higher and maturity rate (b) was lower for Sasso strain than those of Isa Label strain. These results indicated that the Isa Label was more precocious than Sasso strain. The females showed better breast yield while the males showed better thigh and drumstick yield.
free-range system; growth curve; organic birds; slow-growth broilers
