Nutrient composition of fairy shrimp Streptocephalus sirindhornae nauplii as live food and growth performance of giant freshwater prawn postlarvae

Nutritional efficacy of fairy shrimp (Streptocephalus sirindhornae) nauplii, as a live food, was studied for growth performance and survival rate of giant freshwater prawn (Macrobrachium rosenbergii) postlarvae. A feeding experiment was designed with four different feeds: dry commercial feed, fairy shrimp nauplii, Artemia sp. nauplii and adult Moina macrocopa. Results from the nutritional composition revealed that fairy shrimp nauplii had protein and lipid contents of 54.58 ± 2.8 g kg^?1 and 255 ± 2.8 g kg^?1, respectively. The highest value for an individual amino acid in fairy shrimp was lysine (140.7 ± 1.6 g kg^?1). The essential amino acids content in the whole body of the larval prawns was in the range of 66.7–67.5 g kg^?1. Fairy shrimp nauplii had the highest essential amino acid ratio (A/E) of lysine, similarly, in musculature of prawn larvae. Weight gain and specific growth rate of the postlarvae fed with fairy shrimp nauplii were significantly higher than those fed with Artemia nauplii, adult Moina and dry commercial feed. The presented results suggest that S. sirindhornae nauplii can be used as a nutritionally adequate food for freshwater prawn M. rosenbergii postlarvae.     

Effects of dried fairy shrimp Streptocephalus sirindhornae meal on pigmentation and carotenoid deposition in flowerhorn cichlid; Amphilophus citrinellus (Günther, 1864) × Cichlasoma trimaculatum (Günther, 1867)

We investigated the effects of dried fairy shrimp Streptocephalus sirindhornae meal (FS) on skin pigmentation and carotenoid deposition in flowerhorn cichlid. Six experimental diets including three treatments of FS at 10% (FS10), 20% (FS20) and 30% (FS30), two dried Spirulina sp. meal (SP) at 6% (SP6) and 12% (SP12), and a control diet (a basal diet without FS or SP) were offered for 90 days. The results demonstrate an increase in the flowerhorn cichlid skin pigmentation from alternative carotenoid feeding. Fish fed the FS diet displayed higher (P ≤ 0.05) chroma and redness values than those fed with a SP diet. The hue value (measure for skin pigmentation) was high when fish were fed with FS20 for 30 and 60 days (P ≤ 0.01). However, fish also showed high hue values when fed for 90 days with FS10 (P ≤ 0.01). The FS20 treatment gave better results than other treatments in terms of total carotenoid, canthaxanthin, astaxanthin and β‐carotene concentration in the skin and musculature. The optimum level of FS in flowerhorn cichlid diets for achieving the highest skin pigmentation was 20%.