Production of artificial diets for female broodstock of western white shrimp (Litopenaeus vannamei) and study on their singular effect

Advantages of pelleted feeds in terms of storage, transportation and lower costs compared to natural fresh feed justified the replacement of artificial feeds instead of natural ones partially on maturation performances. This study comprised nine treatments (with three replications) including control treatment: polychaete worm (Perinereis nuntia), Squid and calf liver (natural feed); T1: pellet feed with 50% crude protein and 8% crude lipid+ Perinereis nuntia, Squid and calf liver; T2: pellet feed with 50% crude protein and 10% crude lipid+ Perinereis nuntia, Squid and calf liver;  T3: pellet feed with 40% crude protein and 10% crude lipid+ Perinereis nuntia, Squid and calf liver; T4: pellet feed with 40% crude protein and 8% crude lipid+ Perinereis nuntia, Squid and calf liver Perinereis nuntia;  T5: pellet feed with 50% crude protein and 10% crude lipid; T6: pellet feed with 50% crude protein and 8% crude lipid; T7: pellet feed with 40% crude protein and 10% crude lipid; T8: pellet feed with 40% crude protein and 8% crude lipid. In treatments 1, 2, 3 and 4, 50% of the natural diets were removed and pellet foods used instead. The amount of pellet feeds that given daily, was 3.5% of shrimp broodstock biomass. In treatments 5, 6, 7 and 8, the amount of pellet feeds that given daily was 7.5% daily. Feeding was done 4 times a day. GSI in the control (3.23%), treatment 3 (3.20%) and treatment 6 (3.02%) were significantly higher than that in the other treatments (p<0.05). Absolute fecundity in the control (29980 eggs) and treatment 3 (29683 eggs) was significantly higher than other treatments (p<0.05). HSI reached the lowest level in treatment 8 (2.14%). But in treatments 3 and 5 was more than control, but did not any statistical significant (p>0.05). Survival rate in the treatment 8 (26.66%) was significantly lower than other treatments (p<0.05). Generally, In the treatment 3, with the elimination of 50% of the natural foods, and the use of pellet food instead of them, result of comparative indices of reproduction were in desirable proportions.