| Popis: |
An experiment was performed to evaluate the effect of decreased levels of vitamin D3 in the premix and 1,25-dyhydroxyvitamin D3-glycoside (1,25(OH)2D3-glycoside) supplementation on performance, carcass yield and bone quality in 42d old broilers. Seven-d-old male chickens Cobb500® were distributed in a randomized design with six treatments: a control diet with inclusion of vitamin D3 in the premix, without supplementation of 1,25(OH)2D3-glycoside, and five diets with decreased levels of vitamin D3 (100%, 75%, 50%, 25% and 0% about the control) plus the addition of 1,25(OH)2D3-glycoside, 50g ton-1 of diet. The main results were to reduce the tenor of Vitamin D3 in the premix when the addition of 1,25(OH)2D3-glycoside did not affect (P>0.05) the performance, carcass yield and bone quality variables. However, performance (feed intake, gain weight, feed conversion), yield (warm carcass weight) and bone quality (dry weight, length, mineral matter and breaking strength) of broilers fed with diets without vitamin D3 in the premix and with addition of 1,25(OH)2D3-glycoside, which was the single source of vitamin D, had as a result very low (P0,05) o desempenho, o rendimento da carcaça e as variáveis da qualidade óssea. No entanto, as variáveis do desempenho e o rendimento (consumo de ração, ganho de peso, conversão alimentar, peso da carcaça quente) e da qualidade dos ossos (peso seco, comprimento, matéria mineral e resistência à ruptura) de frangos alimentados com dietas sem vitamina D3 no premix, com a adição de 1,25(OH)2D3-glicosídeo como a única fonte de vitamina D, teve como resultado valores muito baixos (P |
