Effect of different levels of Lactobacillus casei on growth performance and digestive enzymes activity of Shirbot (Barbus gryprus)

Lactic acid bacteria are the most common class of bacteria used in aquaculture as probiotic.
In this study the effects of various levels of Lactobacillus casei on the growth performance and digestive enzymes activity of juvenile Shirbot were evaluated.
Four hundred-eighty juvenile Shirbot weighing 40 g were divided randomly in four treatments (in triplicate). Treatments of A, B and C were fed with 5×106 CFU g-1, 5×107 CFU g-1, 5×108 CFU g-1, respectively for 60 days. Control group was fed with free-probiotic diet. After the period, treatments were fed with free-probiotic diet for 15 days. Growth indices and digestive enzymes were examined on days 0, 30, 60 and 75.
In the Treatment B, Specific Growth Ratio, Daily Weight Growth and Relative Growth Rate, after 30 days from the beginning of experiment improved considerably which, compared to control group had significant difference (p0.05).
Results showed that 5×107 CFUg-1 of Lactobacillus casei for 30 days and 5×108 CFUg-1 for 60 days, are the best doses of probiotic.