Background and Aim: The broiler farming industry in Indonesia has enormous potential, with chicken meat that can be optimized by providing adequate and high-quality feed. However, the main raw material for the feed still relies on imported products, which makes it necessary to produce alternative materials from native plants. Therefore, this study aimed to investigate the effect of giving Goloba kusi fruit (GF) (Hornstedtia scottiana [F. Muell.] K. Schum.) on the growth of the small intestine, pectoralis major, and gastrocnemius muscle, as well as the development of broiler chickens.

Materials and Methods: This study used a completely randomized design, in which 300 day-old Chicks were divided into five groups, consisting of 12 chickens in each group with five replications. The GF treatments, namely, 0% (control [CON]), 0.625% (GF1), 1.25% (GF2), 2.5% (GF3), and 5% (GF4) were administered through per kg basal feed. Subsequently, three chickens from each replication were taken, decapitated on the neck, subjected to surgery for histological preparations, and stained with Hematoxylin-Eosin and Periodic acid-Schiff-alcian blue. The variables observed included small intestine morphology, muscle morphology, and chicken growth performance.

Results: The results showed that the small intestine morphology, muscle morphology, and chicken growth performance of the GF4 (5%) group increased significantly compared to the CON group.

Conclusion: The administration of GF with an optimum concentration of 5% through basal feed improves small intestine morphology, muscle morphology, and chicken growth performance.

Keywords: feed additive, Goloba kusi fruit, growth performance, muscle morphology, small intestine.