Effect of Dietary Prosopis farcta on Broiler Performance and Subsequent Physiology under E. coli Challenge.

Abstract This experiment aimed to examine the effects of Prosopis farcta (PF) at varying concentrations (1.0, 2.0, and 4.0 g/kg) and antibiotics (360 g/ton of zinc bacitracin) on the performance and subsequent physiology of broilers during E. coli challenge. A total of 600-day-old Ross 308 broilers were randomly assigned to 10 treatments with six replicates and 10 birds in each. E. coli was orally administered to the birds at 8 and 9 days of age. On day 35, PF at 2–4 g/kg enhanced (p < 0.001) feed intake (FI), body weight (BW), and weight gain (WG) compared to challenged controls and antibiotic-treated groups. Challenged chickens with E. coli decreased (p<0.001) FI, BW, and WG and increased (p<0.015) small intestine relative weight. The relative weight of the spleen increased (p<0.017) in the positive control group. Challenged birds had greater (p < 0.01) Aspartate Aminotransferase (AST) and Alanine Aminotransferase (ALT) levels in their serum. In contrast, unchallenged birds, which received antibiotics or 4 g/kg PF, had lower levels of AST and ALT. Cholesterol decreased (p<0.01) in PF-supplemented groups. Crypt depth was reduced in PF-supplemented birds (p = 0.048), and challenged birds had deeper crypts and lower villus-to-crypt ratios (p < 0.001). Fat digestibility was improved with PF and antibiotic supplementation (p = 0.005). This study indicated that Prosopis farcta at levels of (2–4g/kg) enhanced growth performance, mitigated E. coli-induced metabolic stress, improved gut health, and reduced cholesterol, offering a viable antibiotic alternative in broiler diets under bacterial challenge.