Estudo do desempenho, características de carcaça e níveis de energia metabolizável na ração de frangos de crescimento lento criados em sistema confinado.

Abstract

Two experiments were conducted to study the performance, carcass characteristics and leveis of energy in the ration of slow-growing chickens raised in a confined system. To evaluate the strains 384 birds were distributed in a completely randomized design with four treatments and six replicates of 16 birds each. The treatments were defined according to the different strains used in the experiment: TI — Caipira Francês Barré (Gris Barre Cou Plumé); T2 - Caipira Francês Pedrês (Gris Barre Cou Nu); T3 - Caipira Francês Exótico (Master Gris Plumé); and T4 - Caipira Francês Vermelho (Redbro Cou Nu). In the assessment of dietary energy leveis of 192 birds were distributed in a completely randomized design with four treatments and six replicates of 16 birds each. The treatments were defmed according to the energy leveis of the diets (1 to 28 days) and late (29-90 days), respectively: TI - 3,000 and 3,100 kcal/kg, T2 - 3,100 and 3,200 kcal/kg, T3 - 3,200 and 3,300 kcal/kg. The slaughter was carried out at 77, 84 and 90 days. The Caipira Francês Exótico strain retumed the best results for weight and weight gain. Higher values of feed intake were recorded in Caipira Francês Exótico and Caipira Francês Barré birds. Caipira Francês Exótico and Caipira Francês Vermelho strain had better feed conversion rates and higher values of carcass yields and breast. No significant effects of strain were identified for breast fillet (Pectoris major) yield or sirloin pectoris (Sassami), thigh and drumstick yield. The Caipira Francês Exótico strain had better growth perfomance and carcass yield as when fed diets .'containing 3100-3200 kcal/kg in the diet and slaughtered at 77 days old.