其他摘要：ABSTRACT Streptococcus agalactiae is a major bacterial streptococcosis disease that infects tilapia. This study aimed to analyze a specific and nonspecific immune system in fry tilapia that has been given with S. agalactiae vaccine from N 3 M and N 4 M strain and examine the protective immunity against S. agalactiae N 3 M, N 4 M, N 17 O, NK 1, and N 14 G strains infection. Fry tilapia used in this study has the weight of 7.086±0.948 g and length of 7.443±0.353 cm. The S. agalactiae strains that used were N 3 M, N 4 M, N 17 O, NK 1 ,and N 14 G. Fry tilapia was vaccinated through intraperitoneal injection method with 0.1 mL per fish of N 3 M and N 4 M vaccines. Fish reared in aquarium sizing of 60×30×50 cm 3 with a density of 10 fishes aquarium -1 . Two weeks after vaccination, fry tilapia was tested with 0.1 mL fish -1 of each N 3 M, N 4 M, N 17 O, NK 1 , and N 14 G strains through intraperitoneal injection method. Antibody level measured with indirect enzym-linked immunosorbent assay (ELISA) method. The result of antibody level in vaccinated fish after vaccination of N 3 M, N 4 M vaccine, N 3 M and N 4 M control were 0.767; 0.743; 0.587; and 0.544, respectively. Relative percent survival in N 3 M vaccinated fish after challenged with N 3 M and N 4 M was 87.50% dan 64.70%, respectively, otherwise in N 4 M vaccinated fish was 62.50% dan 76.47%, respectively. N 3 M and N 4 M vaccine strain have better protection as only if it tested with similar bacteria strain.
其他关键词：formalin-killed cell; tilapia; protection; S treptococcus agalactiae ; strains
