Microbial phytase combined with amino acid supplementation reduces P and N excretion of growing and finishing pigs without loss of performance

摘要: Summary The objective of this study was to evaluate the effect a combined low-protein (CP) low-phosphorus (P) diet, supplemented with limiting amino acids and microbial phytase, on performance, nutrient utilization carcass assessment grower–finisher barrows. 4 × 6 crossbreed barrows were continuously housed in metabolism cages from 25 100 kg live weight fed diets, either conventional according recent recommendations (A) or protein reduced (B) phosphorus diets (C) based barley (59–80%), maize (15%) soybean meal (23–2%). Diet A (positive control) contained fresh matter 18.5%, 15.6% 13.6% CP 0.59%, 0.51%, 0.50% P (growth phases I: 25–50 kg, II: 50–75 kg, III: 75–100 kg weight). B low (14.2%, 13.4%, 11.0%), diet C (CP: as B, P: 0.46%, 0.41%, 0.32%). D served negative control (CP C). To lysine, methionine, threonine trypthophan added meet levels A, 800 FTU Aspergillus-phytase per kg supplemented. At end balance periods about 100 (A,B,C) 133 (D) days, slaughtered at weight, carcasses scored loin, biceps femoris, os femoris phalanx prima IV analysed for their (dry matter, protein, fat) mineral (ash, Ca, P, Mg, Fe, Zn) composition. In contrast basal D, reduction did not negatively affect growth, feed efficiency, nitrogen retention overall performances pigs. With C, N excretion via urine significantly thus unit gain decreased by 30%. addition phytase increased apparent digestibility between 25% phase III) 50% II). spite intake (C), absolute daily differ treatments. Thus supplementation 35% (I, II) 44% (III) compared B. Similarly, raised Ca Zn 80%. Generally, meat characteristics affected any strategies employed experiment. Mineralization (bone ash, Mg) also similar all treatment groups. However, led zinc concentration bones, indicating considerably improved release phytate complex. contrast, Fe incorporation into group. general, feeding regimen introduced experiment offers substantial benefits maintaining sustainable environmentally-friendly pork production.