Impact of phytase supplementation on nutrient variability, growth, and digestibility in weaned pigs fed a corn‐SBM complex diet

This study evaluated the effects of different nutrient matrices, with or without phytase supplementation, on growth performance, nutrient digestibility, ileal amino acid (AA) digestibility, and blood inositol in pigs fed a complex diet based on corn-soybean meal. Four hundred newly weaned cross-bred (Landrace × Yorkshire × Duroc) 21-day-old piglets of initial body weight 6.35 ± 1.91 kg were allotted to one of the five dietary treatments: Control (CNT), a corn-soybean-based standard diet; negative control 1 (NC1), a standard diet with reduced available phosphorus (Av.P) (-0.125%), metabolizable energy (ME) (-40 kcal), and crude protein (CP) (-0.3%); NC1 with 500 phytase units per kilogramme (FTU/kg) (N1P5); negative control 2 (NC2), a standard diet with greater reduction of Av.P (-0.150%), ME (-55 kcal), and CP (-0.45%,); and NC2 with 1000 FTU/kg (N2P10). Piglets were housed in a random arrangement based on sex and body weight and data were analyzed as a randomized complete block design using analysis of variance. Results showed that the body weight and average daily gain of the NC2 treatment were lower (p < 0.05) compared to NC2. Gain to feed ratio was greater (p < 0.05) in the CNT and N1P5 treatments compared to the NC1, NC2, and N2P10 treatments. The CP digestibility was higher (p < 0.05) in N1P5 and N2P10 treatments compared to other treatments. Moreover, the digestibility of phosphorus and calcium was higher (p < 0.05) in N1P5 and N2P10 treatments than in CNT, NC1, and NC2 treatments. The digestibility of non-dispensable AA; histidine, isoleucine, leucine, phenylalanine, and valine were increased (p < 0.05) in N1P5 and N2P10 than in CNT, NC1, and NC2 treatments. Nevertheless, the digestibility of dispensable AA, glutamic acid, was higher (p < 0.05) in N1P5 and N2P10 treatments than in CNT, NC1, and NC2 treatments. Blood myo-inositol concentration was higher (p < 0.05) in N1P5 and N2P10 treatments compared to CNT, NC1, and NC2 treatments in phase 2. These results demonstrated enhanced outcomes under conditions of moderate deficiency, whereas more pronounced deficiencies necessitated increased phytase dosages to observe significant improvements. The efficacy of phytase was evident in its ability to elevate average daily gain, gain to feed ratio, phosphorus and calcium, CP, AA, and blood myo-inositol.