PSXI-28 Reducing dietary crude protein and supplementation with amino acids helps mitigate the environmental impacts of growing pigs production determined by the life cycle assessment

Abstract

Abstract This study aimed to evaluate, through life cycle assessment and using experimental data, the environmental impacts of growing pigs’ production (30 to 50 kg) fed diets with reduced crude protein (CP) levels, and supplemented with industrial amino acids. Experiment I (nitrogen and phosphorus balance): 20 crossbred barrows, averaging 31.80 ± 2.39 kg of initial body weight, were housed in metabolic cages and allotted in a randomized block design with four treatments, five replicates and one animal per experimental unit. Experiment II (performance): 44 crossbred barrows, averaging 30.10 ± 0.63 kg of initial body weight, were housed in a randomized block design, with four treatments, 11 replicates and one animal per experimental unit. The treatments for both experiments consisted of four diets containing 18.15, 17.15, 16.15 and 15.15% of CP, and supplemented with industrial amino acids, in order to meet the pig’s requirements of SID amino acids. According to the obtained data (Experiments I and II), the environmental impacts for global warming potential (GWP), acidification potential (AC), eutrophication potential (EU), cumulative energy demand (CED), terrestrial ecotoxicity (TE) and land occupation (LO), per kg of body weight gain, were calculated (CML 2001 method). There was a reduction in some studied environmental impacts as the dietary CP reduced from 18.15 to 15.15%, observing a reduction in the AC from 35.34 to 31.58 g SO2-eq (P = 0.015), there was also a reduction in the EU from 11.90 to 10.31 g PO4-eq (P = 0.001), and the LO was reduced from 2.15 to 1.89 m2-year (P = 0.005), respectively. GWP, CED and TE were not affected (P > 0.05) by the dietary CP reduction, although some variations were observed. It was concluded that the dietary CP reduction, supplementing with industrial amino acids, may help to mitigate the environmental impacts caused by growing pig production for the AC, EU and LO categories.