Guava Leaf Meal (Psidium guajava L.) in Broiler Diets: Effects on Performance, Nutrient digestibilty, and Intestinal Morphology

This study investigated the effect of guava leaf meal (GLM) as a phytobiotic in broilers, focusing on its chemical properties and potential physiological benefits. 135 one-day-old male Cobb broilers were randomly allocated to five treatments (nine replicates per treatment and three birds per replicate): a basal diet with regulated commercial antibiotic (T1), without regulated commercial antibiotic or growth promoters (T2), 1% GLM (T3), 1.5% GLM (T4), and 2% GLM (T5) for 38 d. T2, T3, T4, and T5 reduced feed intake (FI) during the finishing phase (days 20–38, P < 0.0001), but there were no statistical differences in accumulated feed intake (AFI) between treatments. GLM groups had lower ADG during the starter phase (days 3-20, P < 0.05), but there were no statistical differences in accumulated gain. Accumulated feed conversión rate (FCR) was better in T2 to T5 compared to T1 (P < 0.05). GLM groups (T3, T4 and T5) showed significantly higher values of nutrient digestibility (P < 0.05). Duodenum morphology showed that number of villi (P=0.02) and the villus height (P= 0.03) increased with GLM supplementation with respect to control groups (T1 and T2). In conclusion, GLM-based diets enhanced nutrient digestibility and improved intestinal architecture, thereby supporting their inclusion in broiler chicken diets to optimize production efficiency. Highlights: • Dietary inclusion of 1.5-2% Guava Leaf Meal significantly enhanced apparent nutrient digestibility in broiler chickens, particularly crude protein and phosphorus. • GLM supplementation improved duodenal morphology by increasing villus height and villus number, suggesting enhanced nutrient absorption capacity. • Although feed intake was reduced during the finisher phase, overall feed conversion ratio (FCR) was significantly improved with GLM, indicating better feed efficiency. • Guava Leaf Meal demonstrated potential as a natural phytobiotic alternative to conventional antibiotics for optimizing broiler production performance and intestinal health.