Sustainable Aquaculture and Health Management Journal

en Inhibitory activity of native probiotic Bacillus vallismortis IS03 against pathogenic Vibrio harveyi under in vitro and in vivo conditions in Litopenaeus vannamei Bacterial Disease Bacterial Disease پژوهشي Original research papers <div style="text-align: justify;">An excellent alternative for chemical antimicrobial agents to prevent disease in the shrimp aquaculture is the application of effective probiotics. The present study was evaluated the effect of Bacillus vallismortis IS03 as a native probiotic, isolated from digestive tract of Litopenaeus vannamei on pathogenic Vibrio harveyi under in vitro and in vivo circumstances. Co-cultivation of V. harveyi and B. vallismortis showed significantly (P<0.05) decreased the growth of V. harveyi in the treatment groups compared to the control. Cell-free extracts of B. vallismortis IS03 exhibited more appropriate antibacterial effects on replication of V. harveyi. The highest and lowest inhibitory effects were respectively shown in108 and 106 CFU ml-1 of B. vallismortis IS03 cell-free extracts. The probiotic potential of B. vallismortis IS03 was assessed through the groups of control and the experiments 106, 107 and 108 CFU ml-1 salt water once every 3 days from zoea1 process to end point of the study. The probiotic potential of B. vallismortis IS03 was assessed through the groups of control and the experiments 106, 107 and 108 CFU ml-1 salt water once every 3 days from zoea1 process to end point of the study. Shrimp survival was determined after 10 days of challenge with V. harveyi  at 10 5 CFU ml-1 (for the first 5 days) and 10 7 CFU ml-1  (for the second 5 days).The cumulative mortality in the treatment with 108 CFU ml-1 of  B. vallismortis IS03 reached 11.88% compared to 40.63% in the control group. At the end of the trial, total bacterial counts on TSA, total vibrio on TCBS were significantly (P<0.05) lower in the 108 CFU ml-1 treatment group. Bacillus counts on MYP agar in the treatment groups were significantly (P<0.05) higher than the control, also total bacterial counts was lower in the treatment groups, while, no vibrio were grown in the muscle tissues of shrimp treated with probiotics. It is concluded that 108 CFU ml-1 of probiotic, B. vallismortis IS03 has antibacterial efficiency against pathogenic V. harveyi at in vitro and in vivo conditions.</div> Probiotic, Bacillus vallismortis, Litopenaeus vannamei, Vibrio harveyi 54 66 http://ijaah.ir/browse.php?a_code=A-10-274-1&slc_lang=en&sid=1 M Mahjoub m_mahj2013@yahoo.com 10031947532846002342 10031947532846002342 No Iranian Fisheries Sciences Research Institute, Agricultural Research, Education and Extension Organization (AREEO), Tehran, Iran M Mirbakhsh maryam.mirbakhsh@gmail.com 10031947532846002343 10031947532846002343 Yes Iranian Fisheries Sciences Research Institute, Agricultural Research, Education and Extension Organization (AREEO), Tehran, Iran M Afsharnasab mafsharnasab@yahoo.com 10031947532846002344 10031947532846002344 No Iranian Fisheries Sciences Research Institute, Agricultural Research, Education and Extension Organization (AREEO), Tehran, Iran S Kakoolaki bsh443@yahoo.com 10031947532846002345 10031947532846002345 No Iranian Fisheries Sciences Research Institute, Agricultural Research, Education and Extension Organization (AREEO), Tehran, Iran S Hosseinzadeh cd_da@ymail.com 10031947532846002346 10031947532846002346 No Department of Food Hygiene, School of Veterinary Medicine, Shiraz University, Shiraz, Iran