Effect of Bacillus amyloliquefaciens supplementation on intramuscular fat accumulation and meat quality in finishing pigs.

Objective: This study evaluated the potential of Bacillus amyloliquefaciens to improve growth performance and meat quality in finishing pigs.

Methods: Thirty-two female Landrace × Duroc pigs, 21 weeks old with initial body weight 77.45±3.29 kg, were divided into two groups: a control group (basal diet) and a probiotic group (basal diet with Bacillus amyloliquefaciens at 1×109 CFU/kg). Body weight and average daily gain (ADG) were recorded at the start and at fortnight intervals for a 56-d feeding trial. At the end of the experiment, carcass traits, meat quality and intramuscular fat related gene expression of longissimus dorsi muscle were analyzed.

Results: The probiotic group showed significantly higher final body weight and D0-D56 ADG (p < 0.05). Additionally, the probiotic group had greater carcass weight, back fat thickness and marbling score (p < 0.05), while the lean meat percentage remained unchanged. Meat quality analysis revealed that the probiotic group had a higher b* value (5.47) (p < 0.05), and a lower shear value (p < 0.001), but there was no effect on the a* value and water holding capacity. Moreover, probiotic treatment increased the gene expression of fatty acid uptake and regulator, such as LPL, CD36, and SLC27A1 (p < 0.05).

Conclusion: Our findings suggest that the supplementation of Bacillus amyloliquefaciens not only enhanced growth performance and carcass weight in finishing pigs, but also improved marbling and tenderness in the longissimus dorsi muscle through the up-regulation of lipogenic-genes related to fat accumulation. This indicates its potential as feed additive to enhance pork quality.