Nematodes Can Substitute Artemia in a Co-Feeding Regime for Pacific White Shrimp Post-Larvae Reared in a Biofloc Nursery System

This study evaluated nematodes as an alternative to live <i>Artemia</i> when provided in a co-feeding regime to Pacific white shrimp (<i>Penaeus vannamei</i>) post-larvae (PL) reared in a biofloc nursery system. A 20-day experiment employing PL₁₁ was performed for an evaluation of four dietary groups: control [C] (fed exclusively with a dry commercial feed); artificial <i>Artemia</i> [AA] (dry feed composed of extracted and processed <i>Artemia</i> cysts and dry commercial feed); live <i>Artemia</i> and dry commercial feed [LA]; and nematodes and dry commercial feed [N] (<i>Panagrolaimus</i> sp. dry nematodes). The diets were provided twice a day, with the remaining six feed provisions being a commercial dry feed for all experimental groups. A biofloc system was chosen as it offers a potentially sustainable approach to intensive shrimp farming. Alkalinity and pH in the [N] group were significantly higher in the last 5 days of the experiment (<i>p</i> < 0.05), likely causing the significantly lower nitrite levels observed in that same group (<i>p</i> < 0.05). Total and volatile suspended solids were significantly lower in the two live feed groups when compared with [C] and [AA] (<i>p</i> < 0.05). Although PL fed the dry diets exhibited higher growth rates (<i>p</i> < 0.05), the [N] and [LA] groups presented significantly higher final survivals (<i>p</i> < 0.05). No differences were found for survival after a salinity stress test (<i>p</i> ≥ 0.05). These results suggest that nematodes can successfully substitute <i>Artemia</i> in a co-feeding regime for <i>P. vannamei</i> PL reared in biofloc nursery systems.