Effectivity of Arcangelisia flava as immunostimulant to prevent streptococcosis on Nile tilapia, Oreochromis niloticus

This study aims to estimate the effectivity of Arcangelisia flava Merr. application in feed as immunostimulant on total leucocyte, neutrofil, monocyte, lymphocyte, and survivorship of Nile tilapia Oreochromis niloticus infected with Streptococcus agalactiae. Data were descriptively presented and qualitatively described in the form of histograms. Results showed that the highest number of leukocytes was found in treatment E, 81.534 cells mL-1 and the lowest in treatment A, 21.379 cells mL-1. The highest number of neutrophils occurred in treatment E, 35.25% and the lowest in treatment A, 30.26%. The highest number of lymphocytes was recorded in treatment E, 80.50% and the lowest in treatment A, 66.50%. The highest number of monocytes count also occurred in treatment E, 13.00%, and the lowest in treatment A, 9.00%. A. flava could also affect the survivorship. The highest survival was found in treatment E, 91.66%, and the lowest in treatment A, 76.33%. This finding indicated an increase in total leucocyte, neutrophil, monocyte, and lymphocyte, and the survival rate of O. niloticus infected by S. agalactiae at treatment of 200 ppm compared with the control treatment. It reflects that 200 ppm of A. flava is the most effective concentration, in which this dose is immunogenic and protective in raising the immunity of O. niloticus against S. agalactiae infection.