Revista Brasileira de Zootecnia
Print version ISSN 1516-3598
BRUGALLI, Irineu et al. Available phosphorus requirement and effect of particle size on phosphorus bioavailability from meat and bone meal for broiler chicks. R. Bras. Zootec. [online]. 1999, vol.28, n.6, pp. 1288-1296. ISSN 1516-3598. http://dx.doi.org/10.1590/S1516-35981999000600016.
The objective of this work was to determine the nutritional requirement of available P and the effect of the particle size in the P bioavailability from meat and bone meal for broiler chicks. Two hundred and fifty and 450 Hubbard broiler chicks from 1 to 21 days of age, respectively, were allotted to a completely randomized design, with five (requirement) or nine (bioavailability) treatments, with five replicates and ten birds per experimental unit. The P requirements was determined by means of a basal diet with low P level (.15% available P), supplemented with five levels of P from the dicalcium phosphate. The phosphorus availability was estimated using the relation of the regression coefficient, considering the P from the dicalcium phosphate as 100% available. The estimated nutritional requirement values of available P, determined with the Linear Response Plateau (broken line) ranged from .311% (.104% available P/Mcal ME), for weight gain, to .426% (.142% available P/Mcal ME), for tibia ash (g). The average P available values for meat and bone meal with large, medium and small particle size were 106.50, 103.56 and 121.94%, respectively.
Keywords : available phosphorus; phosphorus requirement; particle size; broiler.