The dynamics of phosphorus in the body of Santa Ines lambs fed diets with different levels of this mineral was evaluated, considering the correlations among the levels of phosphorus consumed, in plasma; in saliva, in rumen contents, in feces, and in urine. Eighteen lambs were used with five mo old and 27 kg BW. The experiment was divided into two periods of five weeks, each with nine animals. The animals were individually kept in cages of metabolism study and were fed a basal diet consists of coast-cross grass (Cynodon dactylon, L. Pers.) hay and concentrate with different phosphorus levels (1.9, 2.6, 3.3 g/day) from dicalcium phosphate. On the 15th day, it was initiated the collection of saliva, plasma, rumen contents, feces and urine for the analysis of inorganic phosphorus. Positive correlations were observed among the increase of phosphorus intake and the levels of this mineral in plasma, saliva, rumen contents, feces and urine, indicating that, when absorbed, the phosphorus is distributed throughout the body by the plasma. After saturation in the body, the excess is secreted through saliva, following for the rumen, and reaching the intestine; it is reabsorbed into smaller quantity and excreted via feces. As phosphorus levels increased in the diet, there was significant increase of these mineral levels in saliva, plasma, rumen contents and feces.
animal nutrition; phosphorus levels; ruminants; Santa Inês lambs
