Effect of different levels of dietary Biotronic Top3 on growth performance, feed utilization and body biochemical composition of the white leg shrimp (Litopenaeus vannamei)

This study examined the effects of different levels of dietary inclusion of Biotronic Top3 on growth, feeding and body biochemical composition of whiteleg shrimp, Litopenaeus vannamei reared at the Choebdeh Shrimp Culture Complex, Abadan for a period of 64 days. Shrimp with initial average weight of 4.28+0.05g were stocked randomly in fifteen 300l polyethelene tanks at a density of 25 shrimp/tanks. Triplicate groups of shrimp were hand fed to satiation four times a day using the experimental diet containing 0 (treatment 1, control), 0.5 (treatment 2), 1 (treatment 3) and 2 (treatment 4) grams per kilogram of Biotronic Top3. Biometry was done at the beginning and at the end of the experiment. After 64 days, shrimp receiving diets supplemented with Biotronic Top3 showed significantly better growth performance than those fed the control diet. The highest and the lowest weight gain, specific growth rate and survival rate were recorded in treatments 4 and 1, respectively. Feed conversion ratio, protein efficiency ratio and feed efficiency were significantly different between the treatments (p < 0.05). The highest FCR and the lowest PER were recorded in treatment 1 and the lowest FCR and the highest PER were recorded in treatment 4. Feed efficiency showed a trend similar to that of PER. Morphometric indices (total length, carapace length, orbit length), condition factor and body biochemical parameters were significantly different between the treatments (p < 0.05). The protein content was the highest in shrimp fed the diet containing Biotronic Top3. The highest and the lowest lipid contents were recorded in treatments 4 and 1, respectively. Based on our results and under the rearing conditions used in this study, inclusion of Biotronic Top3 at the rate of 2g/kg diet is recommended for feeding whiteleg shrimp, Litopenaeus vannamei.