Compensatory growth and digestive enzyme activity of Litopenaeus vannamei submitted to feeding restriction in a biofloc system

Feeding restriction is a strategy in shrimp farming management that may promote compensatory growth after feeding is re-established. This study aims to evaluate the effects of two feeding restriction regimens on the compensatory growth and digestive enzymes activity of Litopenaeus vannamei reared in biofloc system. Juvenile shrimp (0.46 +/- 0.18 g) were stocked (320 individuals/m(3)) in 310 L tanks. The experiment comprised two phases: (a) Feeding Restriction (30 days) when shrimp were submitted to three feeding regimes, Control (fed daily), R1F1 (repetitively fasted one day and fed one day) and R2F1 (repetitively fasted 2 days and fed 1 day); and (b) Refeeding (28 days) when shrimp were fed daily. In the restriction phase, shrimp growth and digestive enzyme activities were reduced in R2F1 and R1F1. However, during the refeeding phase, enzyme activities and feed conversion improve significantly in R2F1 and R1F1. Control group attained higher final weight, but its final biomass was similar to R1F1. Litopenaeus vannamei exhibited partial compensatory growth, probably due to improved feed conversion efficiency driven by increased enzyme activity. It is possible to reduce feeding by 50% (R1F1) in biofloc systems for 28 days, without compromising the biomass produced at the end of a 30-day refeeding period.