Indigenous Lactiplantibacillus plantarum in Fermented Diet Improves Blood Metabolites, Growth, and Egg Quality in ALPU×KUB Hybrid Chickens Across Two Generations

The integration of indigenous lactic acid bacteria (LAB) into locally formulated fermented diets may offer a sustainable, antibiotic-free strategy for hybrid local poultry production. This three-phase study isolated, identified, and evaluated indigenous LAB from the colon of ALPU×KUB F1 hybrid chickens in Aceh, Indonesia. Phase I: 64 colonies were isolated on MRS-CaCO₃ agar; 6 Gram-positive isolates were selected and confirmed as Lactiplantibacillus plantarum by 16S rRNA sequencing (99.86% identity). All isolates inhibited Staphylococcus aureus, Micrococcus luteus, Escherichia coli, and Bacillus cereus; isolates P3B5.1 10-1 and P3J1.2 10-6 showed the broadest antimicrobial spectrum and maintained pH 3.0–4.0 under acid challenge. Phase II: selected LAB incorporated in a fermented diet (Fermented Diet) significantly (P < 0.05) elevated plasma protein (4.25 g/dL) and albumin (2.17 g/dL), and reduced cholesterol (118.6 mg/dL) and triglycerides (136.6 mg/dL) in F1 males versus commercial control. Phase III: F2 chickens confirmed progressive multigenerational improvement — P1 (100% fermented) achieved plasma protein 4.86 g/dL, cholesterol 112.1 mg/dL, and superior egg production (83%), albumin height (4.39 mm), and Haugh Unit (67.06 HU). Feed conversion ratio was significantly improved (2.41 vs. 2.89 in control). These findings demonstrate that host-adapted L. plantarum combined with locally sourced fermented feed effectively replaces commercial diets in hybrid local chicken production.