Use of earthworm (Eisenia fetida) meal as a supplement for feeding tilapia juveniles (Oreochromis niloticus)

Earthworm meal comprises a class of food additives with potential to replace or supplement conventional proteins used in fish feed. Considering the potential of earthworm meal, as a protein source for fish feed, this study aimed to investigate the productive performance and the hematological profile of Nile tilapia juveniles fed with a commercial diet enriched with earthworm meal at levels (0.0; 5.0, 10 and 20%). The assay was conducted for 32 days and the productive performance and hematology profile of the animals were evaluated. Tilapia juveniles (n=144; 25.30±3.27g) were distributed in 12 aquariums (300 L) in a static system with partial water changes. The experimental design was completely randomized with four treatments and three replications. There were no significant differences (p>0.05) for performance responses and hematological profile related to variables on hematocrit and CHCM. However, for hemoglobin values the treatment with 20% earthworm meal was similar to the treatments with 5 and 10% earthworm meal, and significantly differed from the control treatment, suggesting its potential as a fish feed supplement. Thus, earthworm meal can be used at 5, 10, and 20% as a supplement for Nile tilapia juveniles without compromising their performance and hematological profile.