The effects of supplementing Napier grass (Pennisetum purpureum) with rock phosphate and steamed bone meal compared with a commercial mineral mix on phosphorus absorption in cattle

Twelve Boran steers with a mean live weight of 215.8 ± 13.9 kg were used in an incomplete Latin Square experiment to compare the apparent phosphorus (P) absorption in cattle when Napier grass (Pennisetum purpureum) was supplemented with Busumbu rock phosphate (BRP), Minjingu rock phosphate (MRP), steamed bone meal (SBM) or a commercial mineral mix (CMM). The steers were housed individually and supplemented with P at 0, 4.5 or 17.5 g P/day. Dry matter intake (DMI) and dry matter digestibility (DMD) were not affected (p > 0.05) by the source of Live weight gains (LWG) were different (p 0.05) across periods. The level of P supplementation had no significant effect (p>0.05) on DMI or LWG. However, increasing the level of P supplementation significantly increased (p 0.05) different from each other. These results suggest that BRP has potential as a source of P for ruminants