M Barzamini - Department of Fisheries, Faculty of Agriculture and Natural Resources, Gonbad Kavous University, Golestan, Iran.
M Harsij - Department of Fisheries, Faculty of Agriculture and Natural Resources, Gonbad Kavous University, P.O. Box:۱۶۳, Gonbad Kavous, Iran
H Adineh - Department of Fisheries, Faculty of Agriculture and Natural Resources, Gonbad Kavous University, P.O. Box:۱۶۳, Gonbad Kavous, Iran
H Jafaryan - Department of Fisheries, Faculty of Agriculture and Natural Resources, Gonbad Kavous University, P.O. Box:۱۶۳, Gonbad Kavous, Iran

This study has investigated the impacts of biofloc on water quality, growth parameters, and whole-body composition of the Litopenaeus vannamei juveniles (initial average weight ۵.۲۳±۰.۲۰ g). Five experimental treatments were designed: Shrimp fed basal diet (Control), ۵ and ۱۰% wet biofloc-supplemented diets (W۵ and W۱۰), ۵ and ۱۰% dried biofloc-supplemented diets (D۵ and D۱۰) for ۳۲ days. Experimental tanks (۵۰ liters) as triplicate for each treatment, was stocked ۱۲ shrimps. During the experiment, chemical and physical water parameters were examined and were not different statistically among experimental treatments. At the end of the experiment, in W۱۰ treatment, the growth parameters were significantly higher than the control treatment. Also, in W۱۰ and D۵ treatments, feed conversion efficiency (FCE) and feed conversion ratio (FCR) were significantly better than the control. Compared to other treatments, significantly better protein efficiency ratio (PER) and lipid efficiency ratio (LER) were observed in W۱۰ treatment. Results indicated that in W۱۰ and D۵ treatments, the protein, ash, and dry matter contents of the shrimp were significantly higher compared to the control treatment. Also, in W۱۰, D۵, and D۱۰ treatments, carcass lipid and fiber contents were significantly higher compared to the control. Overall, the best performance was observed in shrimp fed on ۱۰% wet biofloc-supplemented diet.

White leg shrimp, Microbial flocs, Growth, Body composition, Water treatment