The efficacy of an enzymic cocktail and a fungal mycelium in dephosphorylating corn-soybean meal-based feeds fed to growing turkeys.

A study was conducted to determine the efficacy of phytase, an enzymic cocktail, and a waste Aspergillus niger mycelium to hydrolyze phytate present in corn-soybean meal diets. One hundred turkey poults were assigned to dietary treatments for 2 wk (days 7 to 21). Dietary treatments included: 1) NRC (1994) diet (NRC), with recommended concentration of 0.6% available P (aP) and 1.2% Ca; 2) Phytase diet (PHYT), 1,000 units phytase/kg diet, 0.16% aP, and 0.84% Ca; 3) cocktail diet (COC), 1,000 units of phytase/kg diet plus acid phosphatase (100 units/g of diet), acid protease (42 units/g of diet), pectinase (2.94%), 0.16% aP, and 0.84% Ca; 4) Fungal mycelium diet (MYC), 5% mycelium, 0.16% aP, and 0.84% Ca; and 5) a positive control diet (CTRL+), 0.42% aP, and 0.84% Ca. Turkeys fed the PHYT diet consumed less feed and gained less weight but retained more P than poults fed the CTRL+ or NRC diets. Poults fed the COC diet performed as well as poults fed CTRL+ or NRC diets but retained more P (77%) and Ca (68%). Poults fed the MYC diet retained 79% P, gained the most weight, and were more efficient than poults fed any other dietary treatment. In vitro P release from experimental diets correlated well (R = 0.906) with P retention as observed in the feeding trial. Compared with the diet containing phytase as the sole supplemental enzyme, both the enzymic cocktail and fungal mycelium enhanced performance, bone mineralization, and retention of P and Ca in growing turkeys.