PSVIII-6 - Use of a bacterial consensus 6-phytase variant expressed in Trichoderma reesei in a no inorganic phosphorus, high phytate diet for grow-finish pigs

Abstract: The trial examined if a novel phytase from a bacterial consensus 6-phytase (CP) variant expressed in Trichoderma reesei could maintain performance of grow-finish pigs fed diets without inorganic phosphorus. This trial was done in pigs of commercial genetics that were raised from 26 kg body weight (BW) until slaughter. Diets were formulated using corn, soybean meal, and wheat midds and were based on nutrient requirements from National Swine Nutrition Guide (2010). Three treatments were tested in a randomized complete block design with 9 replicate pens (26 mixed sex pigs/rep): 1) positive control (PC), 2) negative control (NC) without inorganic P (nutrient difference equated to a1000 FTU/kg matrix versus the PC), and 3) NC + CP 500 FTU/kg (CP). Mash diets were fed ad libitum in 5 phases: grower 1 and 2, Finisher 1, 2, and 3 (for total of 84 days). Phytate P in the diets was between 0.29 and 0.26%. Data analysis used ANOVA with mean separation via Tukey honest significant difference with P< 0.05%. No change to dietary P was done in the trial as lameness did not reach the adjustment threshold even in the NC. Lameness caused removal of about 0.7% of animals. At market weight, the results show similar final body weight (BW) for treatments PC and CP, and both were different than NC. Average daily gain (ADG) and average daily feed intake (ADFI) showed similar results for PC and CP, but only the PC was different than NC. Gain to feed (G:F) showed no differences between treatments. These results showed that CP at 500 units/kg improved body weight of pigs fed a no added P diet.