Multiple feedings enhance the growth performance and feed efficiency of juvenile Litopenaeus vannamei when fed a low-fish meal amino acid-supplemented diet

Abstract

In the coming years, supplementation of crystalline amino acids (CAAs) will become a standard practice driven by the trend towards low-fish meal diets. We have evaluated the effect of feeding juvenile L. vannamei several times a day versus two (2×) and four (4×) times using a low-fish meal diet supplemented with CAAs. A total of 1632 shrimp of 1.06 ± 0.16 g were stocked in 16 outdoor tanks of 1 m3 under 100 shrimp/m2. Shrimp were either fed manually, 2× or 4× daily, using one feeding tray per tank, or fed with an automatic feeder to deliver multiple (10) meals during the day or during the day and night (D&N) at programmed times. A diet containing 3% fish meal was prepared to contain supplemental levels of CAAs. After 11 weeks of rearing, survival, growth performance, and feed efficiency of shrimp were significantly affected by feeding frequency and time of feeding. Feeding 2× and 4× daily resulted in a lower survival compared to multiple times during the day or D&N. Shrimp body weight was enhanced with an increase in feeding frequency, from 8.74, 10.95, 11.33, and 11.33 g under 2×, 4×, and multiple feedings during the day or during D&N, respectively. FCR was also significantly affected, reducing from a high of 2.46 under 2× to 1.59 under multiple feedings D&N. Our findings indicate that it is more advantageous to feed juvenile L. vannamei multiple times a day when a low-fish meal amino acid-supplemented diet is used.