Effect of phytase on apparent total tract digestibility of phosphorus in corn-soybean meal diets fed to finishing pigs1

Abstract

Five experiments were conducted to investigate the ability of different phytase products to improve P digestibility in finishing pigs. A corn-soybean meal basal diet containing 0.50% Ca, 0.32% P, and 0.40% Cr(2)O(3) was used to calculate apparent P and GE digestibility. Pigs were individually penned and fed their respective diet for ad libitum intake for 12 d before fecal sampling on d 13 and 14 and blood collection on d 14 for plasma P determination. Experiments 1 through 4 used gilts with across-trial average initial and final BW of 84 and 97 kg, respectively. Pigs were fed Natuphos (Exp. 1), OptiPhos (Exp. 2), Phyzyme (Exp. 3), or RonozymeP (Exp. 4) at 0, 200, 400, 600, 800, or 1,000 phytase units (FTU)/kg (where 1 FTU is defined as the quantity of enzyme required to liberate 1 micromol of inorganic P per min, at pH 5.5, from an excess of 15 micromol/L of sodium phytate at 37 degrees C). Experiment 5 used barrows with initial and final BW of 98 and 111 kg, respectively, and were fed diets containing 0, 500, or 1,000 FTU/kg of Natuphos, OptiPhos, Phyzyme, or RonozymeP. Pigs fed Natuphos (Exp. 1) and OptiPhos (Exp. 2) exhibited a linear and quadratic (P < 0.01) improvement in P digestibility with increasing levels of dietary phytase, whereas pigs fed Phyzyme (Exp. 3) and RonozymeP (Exp. 4) exhibited a linear (P < 0.01) improvement in apparent P digestibility with increasing levels of dietary phytase. In Exp. 5, the improvement in apparent P digestibility with increasing levels of dietary phytase was linear (P < 0.01) for Natuphos, Phyzyme, and RonozymeP, but was linear and quadratic (P < 0.01) for OptiPhos. Based on regression analysis, inorganic P release at 500 FTU/kg was predicted to be 0.070, 0.099, 0.038, and 0.030% for Natuphos, OptiPhos, Phyzyme, and RonozymeP, respectively. These estimates are comparable with those of pigs in Exp. 5, for which the estimated inorganic P release at 500 FTU/kg was 0.102, 0.039, and 0.028% for OptiPhos, Phyzyme, and RonozymeP, respectively, but not for the 0.034% value determined for Natuphos. The effect of dietary phytase on GE digestibility was inconsistent with a linear (P < 0.01) improvement in GE digestibility noted for OptiPhos (Exp. 2 and 5) and RonozymeP (Exp. 4), but the quadratic (P < 0.01) improvement for Natuphos. There was no effect of dietary phytase on plasma inorganic P. The data presented show clear improvements in P digestibility, with the estimated level of inorganic P release being dependent on phytase source and level.

Nutrient digestibility in diets containing low-phytate barley, low-phytate field pea and normal-phytate field pea, and the effects of microbial phytase on energy and nutrient digestibility in the low and normal-phytate field pea fed to pigs

“…Since research with higher phytase Table 5 Coefficients of standardized ileal digestibility of N and AA for low-phytate barley, normal-phytate pea, and low phytate pea fed to growing pigs. inclusion levels in pig diets has shown no further improvement in P digestibility (Traylor et al, 2001;Veum and Ellersieck, 2008;Kerr et al, 2010), more studies with lower amounts of supplemental phytase in LPP based diets should be conducted to establish whether a lower amount of phytase can be used or if there can be total exclusion of phytase. The test ingredients had similar GE values and similarly, their diets' DE and ME values were comparable.…”

Animal production for efficient phosphate utilization: from optimized feed to high efficiency livestock

“…The activity of phytase depends mainly on pH, temperature, dose, and diet composition [24][25][26][27]. Phytase supplementation has mostly been studied in monogastric animals, and improvement of the P digestibility has been observed in Animal production for efficient phosphate utilization Kebreab, Hansen and Strathe 873 [33,34] poultry [21,28 ] and swine [22,29]. However, there is a wide variation in the effect of phytase added at the same phytase dose and type of diet [30], contributing to its unreliability in diet formulation.…”

Variation in coefficient of total tract apparent digestibility of dry matter, nitrogen, and phosphorus and coefficient of total tract standardized digestibility of phosphorus in different corns fed to growing-finishing pigs

“…Phosphorus (P) is an essential nutrient which plays crucial roles in various biological processes including bone formation and energy metabolism (Nafikov and Beitz, 2007;Kerr et al, 2010). Phosphorus is combined with phytate, called 'phytate phosphorus' and is not bioavailable to pigs which lack the digestive enzyme phytase required to remove phosphate from the inositol in the phytate molecule (Baidoo et al, 2003;Knowlton et al, 2004).…”