0
Objective: This study evaluated the effects of enzyme–bacteria co-fermented rapeseed meal (FRSM) as a replacement for soybean meal in finishing pig diets, focusing on growth performance, blood biochemical parameters, meat quality, and lipid metabolism.
Methods: Twenty-eight Duroc × Landrace × Yorkshire finishing pigs, four months old and averaging 60.9 kg body weight, were assigned to four dietary treatments for 45 days. The control group received a conventional corn–soybean meal diet, while in the experimental groups 50%, 75%, or 100% of the soybean meal was replaced with FRSM.
Results: Replacing soybean meal with FRSM did not negatively affect growth performance. Average daily gain and feed efficiency were maintained across treatments, indicating that FRSM can effectively substitute soybean meal without compromising productive performance. From a metabolic perspective, pigs fed FRSM showed improved blood lipid profiles. Total cholesterol levels were reduced compared with the control diet. In the groups receiving 75% or 100% replacement, serum low-density lipoprotein cholesterol, alanine aminotransferase, and urea levels were also lower, suggesting potential benefits for lipid metabolism and liver function. Meat quality parameters were positively influenced by FRSM inclusion. The 24-hour post-mortem muscle pH increased, while drip loss, shear force, and chewiness in the longissimus thoracis et lumborum muscle decreased, indicating improved water-holding capacity and tenderness. Although triglyceride content increased, the overall fatty acid profile improved: the ratio of saturated to unsaturated fatty acids (SFA/UFA) decreased, and the polyunsaturated to saturated fatty acid ratio (PUFA/SFA) increased. In addition, threonine and valine concentrations were elevated. The 100% replacement group showed further increases in umami amino acids, total essential amino acids, and total amino acid content, suggesting enhanced flavor potential and protein quality. Morphological analysis revealed that full replacement with FRSM reduced muscle fiber perimeter in the longissimus thoracis et lumborum muscle, which may be associated with improved meat texture. At the molecular level, FRSM upregulated the expression of MyHC I and MyHC IIa, indicating a shift toward more oxidative muscle fiber types. It also increased the expression of lipogenic genes such as FASN, SREBP1, and SCD, supporting alterations in lipid metabolism consistent with the observed fatty acid profile changes.
Conclusion: Overall, enzyme–bacteria co-fermented rapeseed meal demonstrated clear advantages over conventional rapeseed meal and proved to be a viable alternative to soybean meal in finishing pig diets. Beyond maintaining growth performance, FRSM improved lipid metabolism and enhanced several key aspects of meat quality, supporting its potential as a functional and sustainable protein source in swine production.
Yang L, Tao A, Hu H, Ding M, Chen J, Li X, Chen X, Zou T, You J. Improving Meat Quality and Lipid Metabolism of Finishing Pigs by Replacing Dietary Soybean Meal with Enzyme–Bacteria Co-Fermented Rapeseed Meal. Foods. 2026; 15(3): 587. https://doi.org/10.3390/foods15030587