Aquaculture Reports (Apr 2023)

Effect of fishmeal replacement with dried red wigglers (Eisenia fetida) worm meal on growth and feed utilization, production efficiency, and serum biochemistry in Nile tilapia (Oreochromis niloticus) fingerlings

  • Youssra M. El-Ouny,
  • Sahya Maulu,
  • Mohamed A.A. Zaki,
  • Amira A. Helaly,
  • Abdel Aziz M. Nour,
  • Mohammed F. ElBasuini,
  • Eman M.H. Labib,
  • Riad H. Khalil,
  • Ali H. Gouda,
  • Amira A.A. Hessein,
  • Marc Verdegem,
  • Hala S. Khalil

Journal volume & issue
Vol. 29
p. 101518

Abstract

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This study investigated the effect of replacing fishmeal with red wigglers (Eisenia fetida) worm meal (RWWM) in the diet of Nile tilapia (Oreochromis niloticus) fingerlings. Red wigglers worms (RWW) were culture on a vegetable by-product medium, harvested and dried to obtain red wigglers worm meal. The fish (average weight ± SE: 7.70 ± 0.06 g) were fed with seven diets (30% crude protein and 7.5% crude lipid), in which fishmeal was replaced with 0%, 5%, 10%, 15%, 20%, 25%, and 30% RWWM. The fish was reared in 1000 L fiberglass tanks in a recirculating aquaculture system and were hand-fed twice daily for 90 days. At the end of the experiment, the growth, feed conversion ratio, and energy utilization improved when feeding 15% and 20% RWWM compared with the control diet (P < 0.05). Using broken line regression between growth efficiency and feed utilization, showed the optimum level of RWWM replacing FM in Nile tilapia fingerlings diet was around 21 – 22% of the diet. The whole-body crude protein and ash content were elevated in the fish fed with 10–25% RWWM, while crude lipid and energy contents were elevated in the fish fed with 5–25% RWWM compared with the control group (P < 0.05). The essential and non-essential amino acids profiles of the fish were improved by 15% and 20% RWWM compared with the control (P < 0.05). The plasma glucose was decreased by 15–20% and significantly enhanced in fish fed with 25–30% RWWM diets compared with the control (P < 0.05). The total protein, albumin and globulin increased in the fish fed 15–20% diets and decreased in fish fed the 30% RWWM (P < 0.05). Therefore, this study demonstrates that RWWM could replace 20% fishmeal in the diets of Nile tilapia fingerlings without negatively affecting fish growth and physiological performance.

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