caa a22 4500 605464103 CHVBK 20210128100256.0 cr unu---uuuuu 210128e20150201xx s 000 0 eng 10.1007/s10499-014-9815-1 doi (NATIONALLICENCE)springer-10.1007/s10499-014-9815-1 Evaluation of the effects of probiotics in controlling bacterial necrosis symptoms in larvae of the mud crab Scylla serrata during mass seed production [Elektronische Daten] [Shigeki Dan, Katsuyuki Hamasaki] We aimed to evaluate the practicability of probiotics in controlling larval necrosis symptoms and mass mortality occurred during seed production of the mud crab Scylla serrata. We targeted a bacterium in the family Flavobacteriaceae that causes necrosis symptoms of mud crab larvae. Five candidate probiotic bacterial strains, which showed inhibitory effects against the causative bacterium but were innocuous to larvae, were screened from the seed production environment. Sterile culture medium supernatants of the candidate strains inhibited the causative bacterium through the secretion of extracellular factors. These inhibitory effects were largely reduced when the strains were inoculated into sea water, suggesting medium-dependent production of inhibitory factors. The strain that exhibited the highest inhibitory effect on larval necrosis in 7-day larval rearing experiments was selected as a probiotic strain. In large-scale larval rearing experiments, the probiotic treatment significantly suppressed larval necrosis symptoms and improved larval survival in the early rearing period until the fourth zoeal stage. However, the effect disappeared after the fifth (last) zoeal stage, corresponding to a decrease in inoculated probiotic bacterial counts in the larval rearing water. Almost all larvae had died by the first crab stage. The effectiveness of probiotics developed in vitro has not yet proved practical in commercial-scale seed production. The continuous proliferation of probiotic bacteria and extracellular production as inhibitory factors in larval rearing water are the key factors in developing probiotics for commercial-scale seed production. Springer International Publishing Switzerland, 2014 Bacterial disease nationallicence Biocontrol nationallicence Commercial-scale seed production nationallicence Extracellular factors nationallicence Mass mortality nationallicence Mud crab nationallicence Scylla serrata nationallicence C1 : First-stage crab nationallicence cfu : Colony-forming unit nationallicence DAH : Days after hatching nationallicence MA : Marine agar nationallicence MB : Marine broth nationallicence MG : Megalopa nationallicence NFS-Na : Sodium nifurstyrenate nationallicence Z1-Z5 : First- to fifth-stage zoeae nationallicence Dan Shigeki Tamano Laboratory, National Research Institute of Fisheries and Environment of Inland Sea, Fisheries Research Agency, 706-0002, Chikko, Tamano, Okayama, Japan aut Hamasaki Katsuyuki Graduate School of Marine Science and Technology, Tokyo University of Marine Science and Technology, 108-8477, Konan, Minato, Tokyo, Japan aut Aquaculture International Springer International Publishing 23/1(2015-02-01), 277-296 0967-6120 23:1<277 2015 23 10499 https://doi.org/10.1007/s10499-014-9815-1 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s10499-014-9815-1 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Dan Shigeki Tamano Laboratory, National Research Institute of Fisheries and Environment of Inland Sea, Fisheries Research Agency, 706-0002, Chikko, Tamano, Okayama, Japan aut NATIONALLICENCE 700 1- Hamasaki Katsuyuki Graduate School of Marine Science and Technology, Tokyo University of Marine Science and Technology, 108-8477, Konan, Minato, Tokyo, Japan aut NATIONALLICENCE 773 0- Aquaculture International Springer International Publishing 23/1(2015-02-01), 277-296 0967-6120 23:1<277 2015 23 10499