Studies On The Metabolizable Energy And Crude Protein Requirements For Maintenance In Layer Ducks

Two experiments were conducted to determine the metabolizable energy and protein maintenance of adult Youxian duck in the ceased period. In the first experiment, 30 ducks weighing 1.3kg were allocated to five groups. The birds were forced fed with the same diet by different intake that 0,30,60,90,120g a day. As the result, several regression equations were constructed. As the conclusions the metabolic energy requirement for maintenance is 1061.06 kJ/kgBW拁75, and the feed metabolic ratio is the highest when feed intake around maintenance requirement. It was suggested the feed intake is from 40-60g when the true metabolic energy was measured. In the second experiment, by the means of nitrogen free diet and low nitrogen diet, the birds were fed with 1 20g respectively. The results showed that the amounts of the endogenous nitrogen, surface nitrogen lost and the N requirement were 142.5 6mg/dy 268.48mgId, and 411.O4mg/d.At the same time, the amino acid pattern was calculated according to the analyzed result of endogenous excrete. In this pattern, the concentration of the total sulfur containing amino acid was the highest~ the second was lysine and the third was histidine , and it was different from the pattern of meat type duck.