Study On Calcium And Phosphorus Requirements Of Inner Mongolian White Cashmere Growing Goats

The objective of this study was to determine calcium and phosphorus requirements of Inner Mongolian White Cashmere Growing Goats in different weight and during the anagen and telogen periodby methods of comprehensive experiment, factorial model and regression analysis technique.Part one: Effects of different dietary calcium and phosphorus levels on serum Ca and P concentration, digestibility and metabolism of nutrients and productive performance of cashmere growing goats weighed 25-29kg during the telogen period were studied to determine calcium and phosphorus requirements.Results showed that:①Calcium and phosphorus supplementation in the basal diet had significantly influence on serum Ca concentration (P<0.05).②Dietary Ca and P levels had no significantly influence on DMI and DM digestibility(P>0.05).③NDF digestibility of groupⅢwas significantly higher than that of groupⅠandⅤ(P<0.05),and ADF digestibility was significantly higher than that of all other groups (P<0.05).④N retained and N availability of groupⅣdiffered significantly from groupⅡ(P<0.05).⑤ADG of groupⅣandⅤwas significantly higher than that of groupⅡ(P<0.05),and the feed conversion efficiencies of animals in groupⅣdiffered significantly from those in groupⅡ(P<0.05).The relationships between intake Ca or P and excretion Ca or P were showed in the following regression equations for Ca, y=0.7594x+8.7133(R2=0.9985 P=0.0001 N=5)and for P, y=0.5897x+17.217(R2=0.9544 P=0.0040 N=5),the Ca and P maintenance requirements of cashmere growing goats during the telogen period were 8.71 mg/d/kgLW and 17.22mg/d/kgLW, respectively.It was concluded that calcium and phosphorus requirements of cashmere growing goats weighed 25-29kg during the telogen period were 2.37g/d and 1.48g/d respectively by the method of regression analysis technique.The optimal dietary calcium and phosphorus level was 0.36%-0.42% and 0.25%-0.30% respectively by the method of comprehensive experiment.Part two: Effects of different dietary calcium and phosphorus levels on serum Ca and P concentration, digestibilities and metabolism of nutrients and productive performance of cashmere growing goats weighed 29-32kg during the anagen period were studied to determine the calcium and phosphorus requirements.Results showed that:①Calcium and phosphorus supplementation in a basal diet had significantly influence on serum Ca and P concentration(P<0.05).②Dietary Ca and P levels had significantly no influence on DMI and DM digestibility(P>0.05).③NDF digestibility of groupⅣwas significantly higher than that of groupⅠandⅢ(P<0.05),and ADF digestibility of groupⅡ,Ⅳ,Ⅴwas...