ABSTRACT
The use of probiotic bacteria has been suggested as an important strategy to accomplish reproducible outputs through biocontrol in cultivation systems for marine fish larvae and crustaceans. These bacteria have beneficial effects on fish larvae. This study was done to determine the effect of probiotic lactobacilli on the growth and feeding performance of Persian Sturgeon [Acipenser persicus] larvae via bioencapsulation with Daphnia magna. Daphnia magna was enriched by probiotic lactobacillus for 8 hours in three levels of 4.30, 4.60 and 4.78 log of colonies forming unit per milliliter in suspension of broth, and fed by A. persicus larvae in experimental treatments [treatments of T1, T2 and T[3]]. The Persian sturgeon larvae were fed on D. magnaon the base of 30 percent of their body weight for 30 days. The control treatment was fed on unbioencapsulated D. magna. At the termination of the experiment, the whole body samples of the fish were analyzed according to the AOAC procedures [1990]. The probiotic lactobacillus significantly promoted the body weight, levels of crude protein and carcass dry matter of larvae in experimental treatments in comparison with control treatment [p<0.05]. But in the treatment T[3], the crude lipid and crude energy were significantly decreased [p<0.05]. The maximum level of average crude protein in T[3] [70.27 +/- 0.44%] and its minimum in control [68.51 +/- 0.34%] were obtained. This study indicated that the blend of Lactobacillus had an effect on the promotion of some of the growth and feeding parameters in Persian sturgeon larvae
Subject(s)
Larva/growth & development , Daphnia , Pest Control, Biological , LactobacillusABSTRACT
Optimization of microbial compositions and load in live food during the process of bioencapsulation is one of the most important concerns in aquaculture, as it can promote the growth and feeding parameters of fish larvae. The aim of this study was to determine the growth and feeding performance of Persian sturgeon larvae fed with bioencapsulated D. magna with Saccharomyces cerevisiae. D. magna were bioencapsulated with S. cerevisiae at three concentrations of 5,5.30 and 5.48 Log CPU ml-1 for 10 hours. P. sturgeon larvae were fed using enriched D. magna at 30 percent of their body weight, six times a day. Controlled treatment was fed on unbioencapsulated D. magna. The results indicated that the S. cerevisiae promoted the growth and feeding parameters in P. sturgeon larvae. The final body weight and specific growth rate [SGR] in experimental treatments had significant difference in comparison with control treatment [p<0.05]. Food conversion ratio [FCR] was decreased significantly in treatment group compared to control one [p<0.05]. The maximum of lipid productive value [LPV] and protein productive value [PPV] were obtained in the larvae fed on bioencapsulated D. raagrazat5.30LogCFUml-l]. This study showed that S. cerevisiae had high efficiency in promotion of feeding parameters and growth performance of P. sturgeon larvae
Subject(s)
Animals , Saccharomyces cerevisiae , Fishes , Growth , Feeding Behavior , LarvaABSTRACT
The use of probiotic bacteria has been suggested as an important strategy to accomplish reproductible outputs through biocontrol in cultivation systems for marine fish larvae and crustaceans. The bacterial flora in the larval gut originates from bacteria associated with the eggs, the water in the rearing tanks, and the live food. This study was aimed to determine the effect of commercial and Autochthonous probiotics on growth parameters and survival rate of Rainbow trout [Oncorhynchus mykiss] larvae. Trout larvae [85 +/- 4 mg] were fed diets of Biomar. The experimental diets were supplemented with three blends of probiotic bacteria including lactobacillus, commercal Bacillus and isolated sturgeon gut bacillus in three levels [4.30, 5.30 and 6.30 LogCFU/g of feed] and were fed by Rainbow trout [larvae in 9 experimental treatments. The control treatment was fed on nonsupplemented diet. The experiment was carried out in completely random design. At the end of the period the fishes were biometeried and tested by thermal, salinity, alkalinity and acidity stress. The highest specific growth rate, thermal growth coefficient and feed conversion efficiency were found in treatment Al. The treatments A1, A2, B1, B2, L1 andL3 had significant difference with control [p0.05]. The beter feed conversion ratio was obtained in treatment A1 and L3. Inchalleng test of thermal stress, maximum of survival time. was obtained in treatment B 1. The results of the challenge tests with stress of alkalinity and acidity indicated that the best survival time was in treatment Al and total experimeal treatments had significant difference with control [p<0.05]. No significant difference in salinity challenge test was observed between the treatments [p>0.05]