Phosphorus Digestibility in the Young Pig
A study was conducted to determine the true phosphorus digestibility, the gastrointestinal endogenous phosphorus outputs of cannulated pigs fed a cornstarch-soybean diet. The Latin square designed experiment involved four Yorkshire barrows and four levels of phosphorus from the solvent-extracted soybean meal. True ileal and fecal digestibility values and ileal and fecal endogenous phosphorus outputs associated with the soybean meal were determined by regression analysis. The results indicated that there were no differences (p>0.05) in true phosphorus digestibility values (ideal, 59.0 ± 8.3 vs. fecal, 51.3 ± 7.9%) and endogenous phosphors outputs (ileal, 0.59 ± 0.18 vs. fecal, 0.45 ± 0,21 g/kg of dry matter intake). The researchers conclude that about 51 percent of the total phosphorus in soybean meal is digested in the growing pig. The large intestine does not play an important role in the digestion of phosphorus in soybean meal in the growing pig. Endogenous phosphorus from gastrointestinal sources is a significant portion of the phosphorus in feces of pigs fed soybean meal diets.
Ajakaiye, A. and co-workers. 2003. Determination of true digestive utilization of phosphorus and the endogenous phosphorus outputs associated with soybean meal for growing pigs. Animal Sci. 81(11):2766-2775.
