Studies on the use of probiotics in theudLarval rearing of the shrimp Penaeusudmonodon (Fabricius, 1798)

摘要

The study regarding 'Studies on the use of probiotics in the larval rearing of theudshrimp Penaeus monodon . was carried out by studying the effect of three probiOlicudorganisms. Saccharomyces boulardii. Lactobacillus plal1farulll and Bacillus sublilis. Theudparameters monitored were. level of enrichment in larvae and post larvae, survival. weightudgain, effect on other bacterial flora and resistance to a pathogenic Vibrio harveyii infection.udAttempts were made to find out the optimum enrichment duration and maximum enrichmentudlevels of the above probiotic organisms in Arlemia nauplii and also the difference inudenrichment level between two brands of Arlemia nauplii . The study s carried out in larvaludas well as in post larval stages. Direct additions of probiOlics were carried out in larval stagesudwhile Saccharomyces boulardii and Bacillus sublilis enriched Arlemia metanauplii ere fedudto the larvae in post larval section. Anemia enrichment experiments revealed the maximumudenrichment levels as 3410 for Saccharomyces boulardii. 2093 for Bacillus sublilis and 105udCFUllarva for Laclobacillus plantarum. Enrichment levels also varied between the tOudbrands. 3410 CFU/nauplii for OSI and 1120 CFU/nauplii for Red Dragon brand in the case ofudSaccharomyces boulardii. Significant increase in weight gain and survival rate were noticedudin larvae as well as post larvae in the experiments conducted. Highest enrichment levels wereudnoticed for mysis Ill. Maximum enrichment levels noticed were 1535 CFUllarva forudSaccharomyces boulardii and 2133 CFUllarva for Bacillus subtilis in the larval stages fromudzoea to PL I. while in post larvae it was I CFUllarva for Saccharomyces boulardii and 66udCFUllarva for Bacillus sub/ilis. Laclobacills planlarum could not be detected during theudenrichment study. Addition of Saccharomyces bOl/lardii as ell as Bacillus sub/ilisudsignificantly reduced Vibrio counts during mysis stage as well as during post larval stages.udEffect on sea water agar counts were not significant during larval stages while in post larvaeudsea water agar counts were decreased with the application of Saccharomyces boulardii andudBacillus subtilis. Enrichment of Lactobacillus plan/anlln did not produce any significantudeffect on other bacterial flora. Addition of Saccharomyces boulardii and Bacillus sublilisudincreased the resistance of larvae to pathogenic Vibrio hmwyii infection in larvae as I ell asudpost larvae. About 103 CFU/ml Saccharomyces boulardii broth and 104 to 105 CFU/ml ofudBacillus sublilis cells were necessary to surmount Vibrio han'eyii infection in PL. I. Postudcolonization studies after discontinuing the feeding resulted in 98% reduction inudSaccharomyces boulardii counts and 13% reduction in Bacillus sublilis counts after five daysudfrom PL I. In post larvae Bac/lus sub/ilis showed only 7% reduction in five days from PL 21.udPost larvae fed with live enriched nauplii performed better than those fed with dead enrichedudnauplii. for the parameters studied. From the above study it is evident that Saccharomycesudboulardii and Bacilllls sub/lis can be used as effective probiotic species for shrimpudlarviculture while Laclobacillusplantarum is not a suitable species.