Sarjito, Dilva Maharani, Diana Chilmawati, Pranata Candra Perdana Putra
The whiteleg shrimp (Penaeus vannamei) is a valuable aquaculture species. However, it remains highly susceptible to vibriosis caused by Vibrio harveyi, especially under intensive farming conditions. The present study assesses the efficacy of dietary phycocyanin supplementation as a natural immunostimulant. The goal is to improve immune response, growth performance, and survival in P. vannamei juveniles exposed to V. harveyi. A completely randomized design was implemented with four dietary treatments (0, 2.5, 5, and 7.5 g phycocyanin kg-1 feed) and four replicates per treatment. Shrimp were challenged via intramuscular injection with a V. harveyi suspension (0.1mL at 10⁶ CFU mL-1). Clinical symptoms, total haemocyte count, absolute weight gain, specific growth rate, and survival rate (SR) were measured. Phycocyanin supplementation did not significantly influence growth performance (P>0.05). However, the 5g kg-1 treatment yielded the highest observed growth values. In contrast, immune parameters demonstrated a more pronounced response. Shrimp receiving 2.5 and 5g kg-1 phycocyanin exhibited enhanced haemocyte activity and greater resilience after bacterial challenge. The 2.5g kg-1 dosage produced a more stable immune response and a higher SR than the higher supplementation levels. This suggests a dose-dependent immunomodulatory effect. This study provides new experimental evidence that moderate phycocyanin supplementation optimally enhances immune stability rather than growth performance in P. vannamei under V. harveyi infection. These findings underscore the potential of phycocyanin as a functional feed additive for sustainable disease management in shrimp aquaculture. They also emphasize the necessity of dosage optimization to prevent immune overstimulation. © 2026, Egyptian Society for the Development of Fisheries and Human Health. All rights reserved.
Department of Aquaculture, Faculty of Fisheries and Marine Science, Diponegoro University, Indonesia; Graduate Program in Environmental Science, Graduate School, Universitas Brawijaya, Malang, Indonesia
