Daftar Isi:
  • Abstract. The objective of the study was to investigate the clinical signs, survival rate (SR) and population growth of bacteria in the medium, post-larval Penaeus monodon body and also to analyze the histopathology of post-larval P. monodon. Samples were extracted by soaking method and the extracts were examined for their antibacterial activities against Vibrio harveyi MR 275 Rif. The challenge test were carried out with seven treatments, each one with three replicates. All the shrimps were soaked for 6 hours with V. harveyi MR 275 Rif 107 CFU mL-1 . Chromolaena odorata antibacterial extracts were soaked into shrimp containers in various concentrations (625, 750, 875, 1,000, 1,125, 1,250 ppm). The clinical signs were observed once a day, for 7 days. The disease status of all shrimp was also determined by mortality, population of bacteria in rearing medium and shrimp body, histology and water quality. The result of the challenge test indicated that the concentration of 1,250 ppm of C. odorata extract was able to decrease the mortality (with 14.44%) and the population of bacteria (to 1.40×101 CFU mL-1 ). Clinical signs of tiger prawn were restored to a normal status. The tissues and body of post-larval tiger prawn were normal (healthy) after few days of treatment. The overall results provided evidence that the extract of C. odorata is effective to combat vibriosis on P. monodon and able to serve as a promising resource for the development of therapeutic agents against bacterial infections in shrimp. Key Words: hepatopancreas, mortality, shrimp, vibriosis, bacterial infection