عنوان مقاله [English]
نویسندگان [English]چکیده [English]
Three blends of probiotic bacteria including yeast and bacillus, (Bacillus subtilis, Bacillus lichenifirmis and Saccharomyces cerevisiae) isolated sturgeon gut bacillus were supplemented with experimental diets in three levels (1.56× 10, 3× 106 and 4.5× 106 CFU/liter) and were fed by common carp (Cyprinus carpio) larvae in 3 experimental treatments. The control treatment was fed on non-supplemented diet. The experiment was carried out in completely random design. The rate of feeding was on the base of the 5-6 percent of their body weight for 3 times a day. At the end of the period (35 days) group of fishes were body extracted and other group tested by thermal (40°C), NH3 (5 mg/l ), alkalinity (12) and acidity (2) pH stress. In challenge test of thermal stress, maximum of survival time was obtained in treatment 1.5 × 106 CFU/liter. The results of the challenge tests with stress of acidity and NH3 indicated that total experimental treatments had significant difference with control (p<0.05).but test stress alkalinity no significant difference between the treatments with control (p>0.05) the result of body extract indicate that in the amount K, Ca, Na no significant difference in body extract observed between the treatments (p>0.05) but between treatment 4.5× 106 in the mount fasting blood sugar had significant difference with control (p<0.05). also Kortizol amount in treatment 3×106 had significant difference with control (p<0.05). results indicated that the survival time in some of challenge tests with stress were correlated to probiotic bacteria.