Effects of maternal antibodies against myostatin on post-hatch chicken growth and muscle mass in Sentul Indonesian indigenous chicken

Background and Aim: Myostatin (MSTN) is a negative regulator of skeletal muscle growth, and its suppression could enhance muscle mass. This study investigated the effects of maternal immunization against MSTN on post-hatch growth, carcass characteristics, and muscle fiber size in Sentul Indonesian indigenous chickens. Materials and Methods: Seventy-five Sentul hens were divided into three groups: Control (CON), KLH-immunized (KLH), and MSTN-conjugated KLH immunized (KLH-MSTN). The hens were immunized at 6 months, with boosters at 3 and 6 weeks after initial immunization. Serum and egg yolk antibody titers were measured through enzyme-linked immunosorbent assay. Offspring growth and carcass traits were evaluated at 12 weeks. Histological muscle fiber analysis was performed using ImageJ. Data were analyzed using a one-way analysis of variance and Tukey Honest significant difference tests. Results: Anti-MSTN antibodies were detected in 60% of KLH-MSTN hens 3 weeks post-immunization but declined to 10–30% in later collections. Male offspring in the KLH-MSTN and KLH groups exhibited significantly higher carcass, thigh, and drumstick weights than the CON group, although muscle weights showed no significant differences. In females, only thigh muscle weight in the KLH-MSTN group was significantly higher than in the CON group. Muscle fiber diameters in all measured muscles were significantly larger in the KLH-MSTN group compared to the CON and KLH groups. Conclusion: Maternal immunization with KLH-MSTN increased muscle fiber size but did not significantly enhance overall muscle weight in Sentul chicken offspring, except for the thigh muscle in females. This suggests that MSTN immunization may have limited utility in enhancing muscle growth in this chicken breed. Keywords: carcass traits, maternal immunization, muscle growth, myostatin, Sentul chicken.