The addition of Spirulina platensis extract in feed on gill histopathology and survival rate of Osphronemus gouramy after infected with Aeromonas hydrophila

Prevention of disease in Osphronemus gouramy due to infection with A. hydrophila can be done by using immunostimulants, one of which is using Spirulina platensis extract. The purpose of this study was to determine the effect of S. platensis extract on gill histopathology and survival rate of O. gourami after being infected with A. hydrophila. The fish were divided into three groups: fish without addition of S. platensis extract and infected with PBS (K-); without giving the S. platensis extract and infected with A. hydrophila (K+); and given extracts of S. platensis at 75, 150 and 300 mg/kgof feed and infected with A. hydrophila. The results showed the lowest value of gill damage was obtained in fish with the addition of 75 mg/kg of feed of S. platensis extract (1.22) and the highest damage was in K+ (2.67). The highest survival rate was found in the addition of 75 mg/kg of feed of S. platensis extract (91.67%) and the lowest was in K+ (70.83%). It can be concluded that the addition of S. platensis extract75 mg/kg of feed proved to be the most effective in reducing gill damage and increasing the survival rate of fish.