COMPARING DIFFERENT FEEDING PROTOCOLS FOR IMPROVEMENT OF SHRIMP Litopenaeus vannamei PRODUCTION IN SEMI-INTENSIVE RECIRCULATION

Multiple studies have reported improved growth, productivity and potential for reductions in labor costs when multiple feedings are achieved though automatic feeding systems. Technological development has presented shrimp industry with an increasing number of on-demand (satiation) feeding systems  as well as  traditional timer-feeders  which are  simple, relatively inexpensive and  a  reliable tool for many farmers . Building on previous research that showed improvement in production when increasing from 2 to 6 feedings/day , this trial aimed to test shrimp productivity under different feeding schedules and rations. An 11-week  growth  trial was performed in 32, 750 L tanks in  green water  recirculation greenhouse system, stocked at 30 shrimp/tank (35 ind/m² )  , and fed a 35% protein soy-optimized feed. Water in tank systems was  obtained from a semi-intensive shrimp production  pond.  All tanks were hand-fed the same feed ration  four meals  a day for the first 3 weeks after which a set of 8 treatments was  designed  to compare growth performance at different feeding schedules and feed levels . F ive treatment were fed during day time hours from 7am-7pm with different number of  feedings  per day. One treatment was fed at night from 7pm-7am and two treatments fed the daily ration over 24 hours. Standard ration ( SR) was calculated assuming a doubling of weight weekly until reaching 1.3g then calculated on an expected weight gain of 1.3 g/wk, a feed conversion ratio (FCR) of 1.2.  Feed inputs were increased to 130% SR for weeks 4-5, 145% SR weeks 6-7 then 160% for weeks 8-11. O ne  treatment (SR 175 24h) gradually reaching 175% at week 7 and the SR175 Day only 175% during the last two weeks. All treatments were fed using belt feeders  using lines of feed, except 4 meals per day treatments which were hand-fed. Data presented in Table 1 is result of one-way ANOVA and Student-Newman-Keuls test. Further statistical analysis will be conducted and its results will be presented in the talk.