MULTIPLE FEEDINGS IMPROVE GROWTH PERFORMANCE OF JUVENILE Litopenaeus vannamei REARED UNDER INTENSIVE CONDITIONS

Alberto J.P. Nunes*, Hassan Sabry-Neto, Adhemar R. Oliveira-Neto, Karthik Masagounder
 
LABOMAR - Instituto de Ciências do Mar, Universidade Federal do Ceará, Avenida da Abolição, 3207 - Meireles, Fortaleza, Ceará, 60.165-081, Brazil. alberto.nunes@ufc.br

Farm-raised shrimp are commonly fed by manual broadcasting or with feeding trays, from two to six times daily during grow-out period. Shrimp are slow benthic feeders, feeding continuously but at small quantities throughout the day. The present study investigated the effects of different feeding frequency on the growth performance of juvenile L. vannamei raised under an intensive green-water experimental rearing system. Shrimp of 1.06 ± 0.16 g were stocked at 100 animals/m2 in 16 outdoor tanks of 1 m3 (1.02 m2). After 10 days of acclimation period, shrimp were fed an experimental pellet feed for 70 days. Experimental feed contained on a dry matter basis 32.06% crude protein, 1.93% Lys, 0.87% Met and, 1.33% Met+Cys was lab pelleted. Shrimp were fed manually twice (2x, 7:00 am and 1:00 pm) or four (4x, 7:00 am, 10:00 am, 1:00 pm and 4:00 pm) times daily, with equal amount of feed offered between meals. In the next two treatments, shrimp were fed multiple times a day using automatic feeders either diurnal (Day) from 07:30 am to 05:30 pm (10-h period), or both diurnal and nocturnal (D&N), 24-h period. Observed means for water temperature, salinity and pH were 30.2 ± 1.01oC, 35 ± 2.1 g/L, and 8.5 ± 0.12, respectively. At harvest, shrimp survival was 89.7 ± 9.40% and unaffected by feeding frequency. On the other hand, final shrimp body weight, daily growth, gained shrimp yield, and FCR improved with a higher number of feedings a day. Shrimp body weight improved significantly as feeding frequency increased from 2x, 4x, to multiple feedings a day (diurnal feeding), but settled at D&N. Daily growth, gained yield, and FCR (2.65 ± 0.35 to 1.62 ± 0.03) enhanced significantly as feedings exceeded 2x a day.  In conclusion, juvenile shrimp need to be fed four or more times daily during grow-out period to maximize production performance.