Modeling the effect of daily ration and feeding frequency on growth of redtail shrimp Penaeus penicillatus (Alock) at controlled temperatures

Abstract

Obtaining optimal growth of redtail shrimp at an economic production cost is essential. An experiment was conducted to evaluate simultaneous effects of daily ration and feeding frequency on growth of redtail shrimp at controlled temperatures. Two series were operated contemporarily, one at 25°C and the other at 30°C. the three daily rations were 5, 15, and 25% of fresh body weight in association with three levels of daily feeding frequency: one, three, and five times. Each series lasted for 80 days. The growth rate and the combined effects were studied on day 40 and day 80 for each series. Response surface analyses showed that, at 25°C, two quadratic polynomial equations could describe the daily growth rates (G1 and G2) during growth periods 1 (day 1-day 40) and 2 (day 41-day 80). The optimal daily ration and feeding frequency in terms of maximum growth rate were found at 25°C to be 22.38% of fresh body weight with three feedings/day for growth period 1 and 22.68% of fresh body weight with three feedings/day for growth period 2. At 30°C, two dynamic models were derived for each growth period that included growth optimums of 21.94% and four feedings/day for the first growth period, and 21.27% and four feedings/day for the subsequent growth period.