Effects of replacing soybean oil with palm oil on growth performance, appetite, and gut health in weaned piglets.

Abstract

INTRODUCTION: Weaned piglets face growth challenges due to low feed intake and weaning stress. Palm oil (PO) rich in long-chain saturated fatty acids may optimize nutrition, but appropriate replacement ratios and mechanisms remain unclear. METHODS: 144 weaned piglets were randomly assigned to four groups (CON: 4% soybean oil (SO); T1-T3: 25%, 50%, 100% SO replaced by PO) for 35 days. Growth performance, nutrient digestibility, intestinal health, gene expression, and gut microbiota were measured. RESULTS: T1 and T3 improved average daily gain (ADG) and reduced feed/gain ratio (0-14 d,<0.05); T3 increased ADG (0-28 d) and average daily feed intake (ADFI,<0.05). PO reduced ether extract digestibility (<0.05), upregulated ZO-1/Claudin-1 mRNA (T3,<0.05), and increased hypothalamic NPY/AGRP expression. Gut microbial diversity (OTU abundance) and beneficial bacteria () were enhanced in T3. DISCUSSION: Moderate PO replacement (25%) balances growth promotion and digestibility, while high replacement (100%) improves gut barrier function and appetite. PO regulates growth via fatty acid composition, appetite-related genes, and gut microbiota.