246 Evaluation of the Complete Replacement of Soybean Meal by Rapeseed Meal on Performance and Carcass Composition of Grow-Finishing Pigs

• Published in: Journal of animal science 2023-10, Vol.101 (Supplement_2), p.104-105
• Main Authors: Aymerich, Pau, Soldevila, Carme, Bonet, Jordi, Gasa, Josep, Coma, Jaume, Solà-Oriol, David
• Format: Article
• Language: English
• Subjects: Animal fat; Body weight; Carcasses; Composition; Diet; Finishing; Proteins; Rapeseed; Sex; Slurries; Soybeans; Swine
• ISSN: 0021-8812; 1525-3163
• DOI: 10.1093/jas/skad341.116

Abstract The aim of this experiment was to evaluate the effects of replacing soybean meal (SBM) by rapeseed meal (RSM) as main protein source in diets for grow-finishing pigs. The trial included a total of 1,248 crossbred boars and gilts [Pietrain x (Landrace x Large White), with an initial body weight (BW) of 38.3 ± 5.29 kg (Mean ± SD)], distributed in 96 pens of 13 pigs. Pens were randomly distributed in 2 dietary treatments, balanced by BW, block and sex within each of the 8 slurry pits. The inclusion of SBM and RSM in the growing diets was 13.8% and 20.0%, whereas in the finishing diets (days 52-91) was 10.5% and 14.4%, respectively. Diets were formulated to have the same net energy (NE) value and crude protein differences were below 0.5%. To achieve isoenergetic diets, the inclusion of animal fat was increased by 2.4% and 1.7% in RSM diets compared with SBM for the growing and finishing phases, respectively. Standardized ileal digestible (SID) Lys was kept at 0.95% and 0.86% in the growing and finishing phases, respectively. Performance variables were analyzed by using a linear mixed model with treatment and sex as fixed effects and initial BW as covariate, while pit was included as a random effect. Individual carcass data were analyzed in a linear mixed model with treatment, sex and marketing group as fixed effects, and hot carcass weight as a covariate, and pen within a pit as random effect. During the growing phase, pigs showed lower ADFI when fed the RSM diet (1.68 vs. 1.62 kg; P = 0.002) that resulted in decreased ADG (0.842 vs. 0.803 kg; P = 0.015), but FCR was not affected (2.00 vs. 2.02; P = 0.459). Contrarily, in the finishing phase, ADFI was not significantly reduced (1.98 vs. 1.95 kg; P = 0.586) but less FCR was observed when feeding RSM (2.59 vs. 2.49; P = 0.007). Final BW was not significantly affected (112.0 vs. 110.7 kg; P = 0.404), but hot carcass weight tended to be less in RSM fed pigs (92.2 vs. 91.3 kg; P = 0.078). No significant differences were reported on carcass yield (P = 0.815), carcass leanness (P = 0.850) or backfat thickness (P = 0.850). In conclusion, feeding growing pigs diets without SBM might negatively affect their performance during the growing phase, but those effects can be partly counteracted in the finishing phase without modifying carcass composition.