Abstract:
The main objective of the present paper was to evaluate the influence of the commercial
probiotic BetaPlus® Ultra on the growth performance of the stellate sturgeon after 35 days of
hatching, but the specific objective was to evaluate the food retention efficiency in the transition
period from feeding with natural feed to that with commercial feed. For this purpose, a 93-day
experiment was carried out with 6 experimental variants (5 different probiotic concentrations :
V 1-1.28x1013 CFU, V2-2.56 x1013 CFU, V3 -3.84x1013 CFU, V4 – 5.12x1013 CFU, V5 -6.4x1013 CFU
and V6- control variant, in duplicates). The experiment started with a number of 6000 exemplars of
35-day post hatched larvae (500 specimens/rearing unit) with a mean individual weight (± SD) of
0.35 ± 0.02 g and a total length between 3-5 cm. According to the rearing technology, sorting was
carried out throughout the experimental period which led to the division of the experiment into
9 different experimental stages according to feeding protocol.
Feeding efficiency, expressed by FCR and protein retention, indicated by PER shows an
insignificant increase (p> 0.05) in the V2 variant and an insignificant decrease in the case where the
probiotic (V6) was not administered. Therefore, according to this experiment, a concentration of
2.56x1013 CFU / kg of commercial probiotic BetaPlus® Ultra represents an optimum value for
promoting the growth, feeding efficiency and retention of proteins of trout after more than one gram.
