EFFECTS OF MARINE SYNBIOTIC SUPPLEMENTED AND/OR FERMENTED MICRODIETS ON THE EUROPEAN SEA BASS LARVAE LENGTH GROWTH AND EARLY WEANING  

 
Salem*, Ahmed Md.
 
National Institute of Oceanography & Fisheries (NIOF),
Quiet Bay Castle, El-Anfoshy, Alexandria, Egypt.,
Mobile: +201000323014; Fax: +2034801174;  
Email: drsalemniofaqua@gmail.com  
 

Egypt, the 9th world aquaculture producer is also the 1st Mediterranean Sea, Arab and African aquaculture producer (FAO, 2014). Egypt marine aquaculture still depending on fry collected from natural resources (43 million fry, only 0.062 million fry of them recorded as Seabreams and Seabasses fry); although Egypt had 6 hatcheries producing 8.916 million fry, only 2.166 million were Seabass fry (GAFRD, 2013). Not enough or misbalanced or low quality live feeds and microdiets affecting negatively marine hatcheries larval productivity and quality (Salem et al., 2012; Salem, 2014). Marine probiotics and synbiotics enhanced 40dph early weaned European Seabass larvae growth, survival performances and quality (Salem, 2014; Salem et al., 2015).

The present study conducted in the marine hatchery (El-Anfoushy) of the Fish Reproduction & Spawning Lab., NIOF, Alexandria, Egypt. The experimental full sib European sea bass Dicentrarchus labrax newly hatched larvae were obtained from hormonal induced spawning, fed on live foods (rotifers and artemia) from 5 dph and reared in the same rearing tank in the marine hatchery larval rearing unit until 30dph then restocked in the experimental small tanks for 5 days co-feeding with treated Orange® P 1/2 Small microdiets with 100-200 micron to 35dph and then fed for 10 days with treated Orange microdiets to 45 dph early weaning according to (Salem and Ibrahim, 2015). The 5 treatments were green water  using Nanochlorapsis salina algae with non treated microdiets control (G), solid state fermented microdiets as positive control (GSF), marine Bacillus subtilis HS1 Probiotic bacteria and marine Chitosan Prebiotic mixture synbiotic solid state fermented microdiets (MSF), marine Synbiotic supplemented microdiests (MSS), marine synbiotic fermented and resupplemeted microdiets (MSSF) in 30 l tanks in triplicates. Larvae samples were randomly collected from treatments tanks for body length to statistically deteremine the length growth performance.

The results of the 45dph early weaned European Seabass larvae showed that the effect of using (G, GSF, MSF, MSS and MSSF) treatments on final total length (FTL) and final standard length (FSTL) in mm of 45dph larvae showed that the best significant (P < 0.05) recorded by MSF and MSS while the smallest significant (P < 0.05) recorded by G. The results of the length gains between 30 dph as initial and 45 dph as final lengths showed that the total length and standard length gain in mm; total length and standard length ADG in mm/day and total length and standard length SGR% in %/day showed that the best results achieved by MSS.