Greenwater, Marine Bacillus subtilis HS1 Probiotic and Synbiotic Enriched Artemia and Rotifers Improved European Seabass Dicentrarchus labrax Larvae Early Weaning Length Growth, Survival, Water and Bacteriology quality

Abstract

Abstract:The present study conducted in Fish Reproduction & Spawning Lab., NIOF, Alexandria, Egypt. European sea bass Dicentrarchus labrax newly hatched larvae from 8 dph to the 40 dph was reared according to (Süzer et al., 2011). The 6 tanks was green water with N. salina Algal count not less than 300000 cell/ml. The experimental treatments using green water using N. salina as positive control (G), green water plus marine probiotic bacteria (G+MP) and green water plus synbiotic (G+S).4 hours enriched rotifers Brachionus plicatilis started from the 7 th dph until the 14 th dph, the beginning of cofeeding on 6 hours enriched Artemia fransiscana (GSL) nauplii started and rotifers reduction started in the 18 th dph and stopped from the 20 th dph and artemia napulii fed alone until the 25 th dph, 25dph larvae started feeding on artemia metanauplii and cofeeding with Orange® P 1/2 Small microdiets with 100-200 micron to 35dph. From the 35 th dph artemia metanapulii stopped and larvae fed only on O.range® until the end of the experiment (the 40 th dph). The treatments were green water using Nanochlorapsis salina algae (G), greenwater plus marine Bacillus subtilis HS1 Probiotic bacteria (G+MP) and greenwater plus synbiotic (G+S) in 30 l tanks in duplicates. Microbiological measurements were performed in water samples in every larvae critical stage (7, 14, 21, 25, 35 and 40dph) for colony forming unit (CFU) of total bacterial count, Vibrio, Staphylococus, Aeromonas and Bacillus. Also water quality measurements were performed in the beginning of the experiment in 2 pm and in the same time in the 7, 14, 21, 28, 35 and 40 dph newly hatched larvae tanks. Finally, the results of the 40dph early weaned larvae showed significantly (p<0.05) higher final total length achieved by (G+MP) followed by (G+S) and the lower significant (p<0.05) recorded by (G) treatment. The bacterial counts of the Aeromonas not detected in all treatments, the other bacterial counts showed promising results of (G+MP) and (G+S) than (G) treatments in both inhibiting potentially pathogenic bacteria counts and also in improving the potentially useful bacterial counts.

Molecular identification of bacteria isolated from culture medium of rotifer fed on fishery waste diet

“…B. cereus is a gram-positive, aerobic-to-facultative, spore-forming rod-shaped bacteria having wide distribution in the environment (Bottone 2010). B. cereus is a pathogenic bacterium that is harmful to humans and causes foodborne illness, but some strains of B. cereus have long been known as probiotic bacteria in rotifer culture (Md et al 2015;Loka et al 2016). In spite of that, B. cereus was also reported to have a significant role in enhancing growth performance of fish fingerlings (Chandran et al 2014;Vargas-Albores et al 2017;Sultani et al 2019).…”

Sustainable fish production in Egypt: towards strategic management for capture-based aquaculture

“…Inadequate live feeds and micro diets negatively affect the quality and productivity of marine hatchery larvae. The lack of appropriate feed often leads to early disposal of production due to high mortalities during transport and stocking (Salem et al 2015). The issue becomes more critical, particularly with import restrictions due to foreign currency shortages.…”