93 Efficacy of Bacterial 6-Phytase and its Optimal Supplementation Level on Bone Parameters, Nutrient Digestibility, and Growth Performance of Nursery Pigs

Abstract

Abstract This study aimed to determine the optimal supplemental level of bacterial 6-phytase (CJ BIO, Korea) based on bone parameters, nutrient digestibility, and growth performance of nursery pigs. Seventy-two weaned pigs (5.8 ± 0.5 kg BW) were allotted to 6 treatments based on RCBD with initial BW and sex as blocks and fed in 3 phases (P1/P2/P3 for 14/10/14 d, respectively). The treatments consisted of a negative control diet without phytase formulated meeting requirements of NRC, (2012). The other 5 treatments were a basal diet formulated with 0.12% Ca and P deficient with increased supplemental phytase (0, 500, 1,000, 2,000, and 5,000 FTU/kg feed). Titanium dioxide (0.4%) was added to P3 diets as an indigestible marker to measure AID of nutrients. On d 45, all pigs were euthanized to collect ileal digesta to measure AID, and third metacarpus to measure bone parameters. Data were analyzed using SAS 9.4. The supplementation of phytase from 0 to 950 FTU/kg feed increased (P < 0.05) the ADG (0.32 to 0.40 kg/d). Increasing phytase supplementation from 0 to 5,000 FTU/kg increased (linear, P < 0.05) AID of CP (76.8 to 79.5%), P content (4.6 to 5.2% of DM) and ash content (26.2 to 28.8%). The supplementation of phytase from 0 to 950 FTU/kg feed increased (P < 0.05) P content (17.6 to 18.1% of ash) and from 0 to 1,900 FTU/kg feed increased (P < 0.05) bone breaking strength (222 to 329 N). Phytase supplementation (0 vs. 1,000 to 5,000 FTU/kg) increased (P < 0.05) AID of EE (65 to 73%), and P (79 to 84%). In conclusion, phytase supplementation improved bone breaking strength, bone ash and P content, nutrient digestibility, and growth performance. The supplementation of phytase between 950 and 1,900 FTU/kg feed provided the most benefits for growth performance, bone parameters, and nutrient digestibility.