Aquaculture | 2019
Growth performance and survival of Holothuria theeli (holothurian) fed with feces of Tripneustes depressus (echinoid): A multi-trophic aquaculture approach
Abstract
Abstract Integrate Multi-Trophic Aquaculture (IMTA) for deposit-feeding sea cucumbers and herbivorous sea urchin is currently a booming industry worldwide, including South America. Hence, it requires novel biotechnological protocols for culturing juvenile sea urchins and sea cucumbers with a high quality of natural food that meet organisms nutritional needs. This study evaluated the effect on the growth performance (Specific Growth Rate, Feed Conversion Ratio, Feces Production) and survival of the sea urchin Tripneustes depressus (producer of feces) and the sea cucumber Holothuria theeli (consumer sea urchinʼs feces). Two independent experiments were conducted. For T. depressus, experiment #1: diet of seaweeds (D1: Padina durvillaei, D2: Sargassum ecuadoreanum, D3: Kappaphycus alvarezii, D4: mix of three seaweeds) and size categories (small, S: 15.0\u202f±\u202f1.1\u202fmm test diameter, TD and large, L: 25.0\u202f±\u202f1.1\u202fmm TD) were considered. For H. theeli, experiment #2: feces of diets of experiment #1 and sediment (with, without sediment) were considered. Experiment #1, SGR: small and large sea urchins fed P. durvillaei grew and gained weight faster, respectively (S: 3.0\u202f±\u202f0.05\u202fcm TD, 7.9\u202f±\u202f0.2\u202fg; L: 2.1\u202f±\u202f0.1\u202fcm TD, 5.3\u202f±\u202f0.1\u202fg). Sea urchins fed P. durvillaei and those of small size had lower FCR (diet: 7.2\u202f±\u202f0.6\u202fg; size: 13.1\u202f±\u202f2.4\u202fg, P