The Effects of Live and Artificial Diets on Feeding Performance of Winter Flounder, Pseudopleuronectes americanus, in the Hatchery

Abstract

Winter flounder, Pseudopleuronectes americanus, are capable of releasing hundreds of thousands of eggs annually, but because of the vulnerability of the small, early life stages, there is high natural mortality, and few survive to maturity. Captively spawning, rearing, and releasing animals at a size or age beyond this period of high mortality may enhance stocks. The objectives of this research were to determine how different diets (both live and formulated) influenced hatchery survival and growth of juvenile winter flounder. Live feeds included post-nauplii of brine shrimp, Artemia salina; white worms, Enchytraeus albidus; and common burrower amphipods, Leptocheirus plumulosus. Fish reared on live feeds exhibited significantly higher survival (P < 0.0001) and growth (P < 0.01) than those reared on formulated feed, with fish fed white worms exhibiting the highest growth rates. This study provides hatchery feeding strategies that may ease the transition of flatfish released into the wild for stock enhancement.

The Effects of Live and Artificial Diets on Feeding Performance of Cultured Winter Flounder, Pseudopleuronectes americanus, in the Wild: Survival, Feeding, Growth, and Nucleic Acid Analyses

“…Growth rates of worm‐reared fish were slightly lower in the cages (0.008 G SL /d; 0.31 mm/d) compared to growth performance in the hatchery (0.010 G SL /d; 0.37 mm/d; Walsh et al ). However, brine shrimp‐, amphipod‐, and pellet‐reared fish all exhibited higher growth rates while in the cages.…”

“…Both wild fish (58.48 ± 1.22 mm standard length, SL) seined from the cove and worm‐reared fish (38.80 ± 0.52 mm SL) were statistically larger than brine‐ (34.82 ± 0.51 mm SL), amphipod‐ (32.28 ± 0.55 mm SL), and pellet‐reared (32.26 ± 0.69 mm SL) fish at the start of cage trials (Fig. ); however, all hatchery‐reared fish were from the same cohort with size differences resulting from the provision of different hatchery feeds (Walsh et al ). All fish were not released at the same time; rather, releases were scattered over a 27‐h period (September 3–4, 2008) so that all retrievals occurred during daylight hours (Fig.…”

Body Condition Peaks at Intermediate Parasite Loads in the Common Bully Gobiomorphus cotidianus

“…observ . ), which are less nutritious [55]. A complementary explanation is that water turbidity in Lake Waihola reduced feeding rates of common bully, as demonstrated experimentally [56].…”

Salinity of the growth medium is important for production potential and nutritional value of white worms (Enchytraeus albidusHenle)

“…biomass, eicosapentaenoic acid, fish feed, mass production, protein content been used to culture E. albidus, its nutritional composition when used as live feed is suitable for fish species demanding high protein (50%-70% of dw) and lipid content (15%-20% of dw) including omega-3 HUFAs (Bouguenec, 1992;Fairchild et al, 2017;Walsh, Fairchild, Rennels, & Howell, 2015).…”

“…Nevertheless, various authors have recommended very different salinity of the substrate in which E. albidus is cultured ranging from non-saline tap water (ISO, 2004;Ivleva, 1973;Memis, Celikkale, & Ercan, 2004) to seawater 25-31 ppt (Fairchild et al, 2017;Walsh et al, 2015). In order to exploit the full potential of E. albidus as a possible new source of protein and lipids for fish feed, more research is needed to optimize mass production conditions.…”