The potential for propagation of the commercial sea cucumber Isostichopus fuscus (Ludwig, 1875) by induced transverse fission

This study evaluated the potential to propagate asexually the brown sea cucumber Isostichopus fuscus by induction of transverse fission, and its ability to survive, grow and regenerate body parts into a whole animal. Two independent experiments were performed. Experiment 1: sixty-two adult animals (18.8 ± 0.2 cm and 368.1 ± 7.2 g) were cut six centimeters from the rear, and during this process they eviscerated. Survival of body-parts (anterior and posterior) of animals and regeneration times were evaluated, until all individuals showed complete regeneration in terms of its morphology (lasted 13-wk). Animals were maintained in starved condition and had high survivorship (100%). Complete regeneration occurred within 84 to 95 days. Experiment 2: 48 completely regenerated posterior body-parts of I. fuscus (with mouth and anus well developed) were used (lasted 13-wk) and animals were fed ad libitum four diets in powder and two controls: diet A with Ascophyllum nodosum and Sargassum spp; diet B was a commercial shrimp feed with a mix of proteins from marine animals and vegetal material; diet C with Padina durvillaei and Sargassum ecuadoreanum; and diet D with a mixture of diet C with calcium citrate and Vitamin D. Two controls were used. Survival was not affected by diet but this significantly affected somatic growth rate in length and weight. The fastest growth rates (in length and weight) were for diet B (0.50 ± 0.10 cm month−1 and 0.57 ± 0.11 g month−1) and the lowest for diet A (0.15 ± 0.10 cm month−1 and 0.11  ± 0.07 g month−1). No growth was detected in controls. I. fuscus had a high potential for regeneration. Our results encourage further research to explore the feasibility of mariculture and/or restoration programs of wild sea cucumber populations in Ecuador, using asexual propagation techniques for I. fuscus.