Potential of organic acid blend as an antibiotic substitute in weaned piglets

Introduction: In the era of antibiotic prohibition, there is an urgent need to develop green and efficient alternatives to mitigate the economic losses associated with antibiotic bans. Organic acids (OA) are a class of substances that have long been used as feed additives due to their bacteriostatic properties, ability to lower feed pH, and enhance digestive enzyme activity.
Objectives: This study aim to evaluate the effects of dietary OA on growth performance, antioxidant capacity, intestinal barrier function, and fecal microbiota in weaned piglets compared with antibiotic growth promoters (AGP).
Methods: Ninety weaned barrows (24 ± 1 days old; 7.40 kg initial BW) were randomly assigned to three diets: basal diet (NC), basal diet + antibiotics (PC), and basal diet + organic acid blend (OA). Each treatment had six replicates with five piglets per pen. After 42 days, one piglet per pen was sampled for plasma and intestinal analyses.
Results and expectation: AGP significantly improved growth performance and reduced diarrhea compared with NC (P < 0.05). OA tended to increase body weight (P = 0.07) and average daily gain (P = 0.06) and decreased diarrhea incidence (P = 0.05). OA supplementation increased plasma catalase (CAT) activity while reducing malondialdehyde (MDA) and inflammatory factor levels (P < 0.05). The mRNA expression of antioxidant related genes was upregulated, and the villus height/crypt depth ratio and tight-junction gene expression were improved (P < 0.05). Fecal microbiota composition and volatile fatty acids were not significantly altered. These findings suggest that dietary OA can enhance antioxidant defense and intestinal integrity in weaned piglets, supporting its potential as a safe and effective alternative to AGP in swine production.