USE OF Bacillus subtilis IN MICROPARTICULATE DIETS FOR PRODUCING BIOSECURE Peneaus japonicus POSTLARVAE

EI-Dakar,, A. Y.; Gohar, Y. M.

doi:10.21608/jappmu.2004.239471

USE OF Bacillus subtilis IN MICROPARTICULATE DIETS FOR PRODUCING BIOSECURE Peneaus japonicus POSTLARVAE

Document Type : Original Article

Authors

A. Y. EI-Dakar, ¹
Y. M. Gohar ²

¹ Fish Resources and Aquaculture Department, Faculty of Environmental Agric. Sciences, Suez Canal Univ., EI-Arish. Egypt.

² Microbiology Division, Fac. of Science, Alex. Univ., Alexandria, Egypt

10.21608/jappmu.2004.239471

Abstract

Two separate feeding trails were carried out to study the effect of Bacillus
subtilis in probiotic micro particulate diets on survival, growth and pathogen resistance
of Penaeus japonicus larvae and postlarvae. The first one was done on an
experimental scale while the second was done on a large scale as an application trail.
Probiotic diet was formulated by adding 500 mg of Bacillus subtilis (7x10⁷ cell/g) per
100 g basal diet that containing 53% protein with particles size of 350-800 IJm. In the
experimental trail, 1000 postlarvae of P. japonicus at substage of PL1 were randomly
distributed, stocked into six circular-conical bottom fiberglass tanks; each one had a
capacity of 100-L. In the application trail, two 3.6 m³ U-shape fiberglass tanks were
used to stock 180,000 hatched nauplii of P. japonicus in each. Survival of postlarvae
fed probiotic diet was higher than those fed the basal diet. Enhanced growth was
generally obtained in postlarvae fed probiotic diet compared with the basal diet in
either experimental or application trails. Challenge of bacteria to pathogen, as a
universal probiotic bacterium, was studied by evaluating its action against three
different aquaculture bacterial pathogens, namely, Aeromonas hydrophila,
Edwardsiella tarria, and Vibrio proteolyticus. A considerable change in the intra and
extra-cellular proteins profiles of the three bacterial pathogens were observed when
electrophoresed via SOS-PAGE techniques after mixing with B. subtilis. The
proteolytic activity of the bacterial pathogens exhibited a sharp decrease when
subjected to B. subtilis extra-cellular products. In addition, it was noted a positive
effect of the extra-cellular products of B. subtilis against the pathogens and on
reducing the antibiotic susceptibility when presented in culture water or in feed of
shrimp.

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