Bone densitometry as an indicator of percentage tibia ash in broiler chicks fed varying dietary calcium and phosphorus levels.

摘要: The relative sensitivity of tibia bone mineral content (BMC) and density (BMD), percentage ash (ash), shear force as indicators for dietary Ca P was compared in 3-wk-old broiler chicks. One hundred eight 7-d-old chicks were grouped by weight into 6 blocks 3 cages each with birds per cage. Three corn-soybean meal-based diets randomly assigned to within block. low P, medium adequate formulated contain 4.0, 5.1, 7.8 g total P/kg feed, respectively; 6.7, 10.0 Ca/kg respectively. fed the experimental 14 d. On d 22, killed, tibiae removed from birds/cage. Weight gain, feed intake, efficiency, BMC, BMD, force, determined. BMC BMD determined using dual energy x-ray absorptiometry. Correlations among various status variables Growth performance criteria increased linearly, linearly quadratically concentrations increased. correlation coefficient between or 0.89, 0.91, 0.50, 0.88, 0.48, 0.92, 0.93, 0.67, coefficients linear regression 0.56. model predicting follows: = 24 + (240 x BMD) an r2 86%. It is concluded that chicks, ash, may be more sensitive than measured absorptiometry used predict ash.