Pigs were self-fed one of six dietary concentrations (.20, .30, .40, .50, .60, .70%) of available phosphorus (AP) from 13 to 70 pounds body weight. Dietary available phosphorus concentrations of at least .50, .40, and .40% were needed for pigs weighing 23, 43, and 63 pounds, respectively, to maximize daily body weight gains and gain:feed ratios. Based on these data, the dietary AP needs of 13- to 70-pound pigs experiencing a moderate level of antigen exposure are 1.25 to 1.5 times greater than current NRC (1) estimates for similar weight pigs.
Iowa State University
Stahly, Tim S. and Cook, D. R., "Dietary Available Phosphorus Needs of Pigs From 13 to 70 Pounds Body Weight" (1998). Swine Research Report, 1997. 1.