Impact of dietary supplementation with fennel seed (Foeniculum vulgare var. dulce) on growth Performance, carcass characteristics, meat quality, intestinal measurements, and cecal microbiota in broiler chickens.

This study evaluated the effects of dietary fennel (Foeniculum vulgare) seed supplementation during the grower and finisher periods on growth performance, carcass characteristics, meat quality, intestinal morphology, and cecal microbiota in broiler chickens. A total of 300 one-day-old Arbor Acres chicks were randomly assigned to three dietary treatments, each with 4 replicates of 25 chicks: a control group (CG), experimental group 1 (EG1) receiving 0.3% fennel seed, and experimental group 2 (EG2) receiving 0.6% fennel seed, over a 42-day trial. Antimicrobial activity of aqueous fennel extract against Staphylococcus aureus ATCC 25,923 and Escherichia coli ATCC 25,922 was confirmed in vitro. The findings showed that growth performance parameters were slightly reduced at the beginning in the fennel-fed groups, possibly due to dietary adaptation; however, feed efficiency improved during the later stages. Meat quality analysis revealed a significant reduction in cooking loss (P = 0.017), with no negative impact on water-holding capacity, proximate composition or pH, while, a less pronounced pH drop was noted in the experimental groups compared to the control during the 24 h post mortem. Fennel supplementation significantly enhanced duodenum thickness (P = 0.001) and cecal length (P = 0.039). Moreover, beneficial bacteria such as Lactobacillus spp. increased significantly, while Salmonella spp., Enterobacteriaceae, and total aerobic bacteria decreased significantly in the cecum. These findings suggest that fennel seed supplementation can be a natural alternative to antibiotics, enhancing broiler health, meat quality, and intestinal integrity without compromising production performance.