Effects of protein and carbohydrate levels on survival, consumption and gonad index in adult sea urchinStrongylocentrotus purpuratus(Stimpson 1857) from Baja California, Mexico

Abstract

A greater understanding of dietary protein and carbohydrate levels with regard to gonad production in Strongylocentrotus purpuratus would increase our nutritional knowledge of this sea urchin and guide the development of formulated diets for such aquaculture target species. A total of 255 purple sea urchins were captured from Ensenada Bay, Mexico, and maintained in 200-L tanks for 9 weeks. Formulated diets that contained 30%, 26%, 23%, 20% and 17% of protein and 42%, 46%, 50%, 54% and 58% carbohydrates were offered ad libitum. Survival was affected by diets; urchins that were fed high-protein-low-carbohydrate diet experienced decreased survival. No significant differences were found in gonad index, but gonad production efficiency was lower in urchins that were fed a medium-low-protein-medium-high-carbohydrate diet. Urchins that were fed high carbohydrate levels utilized protein more efficiently and showed better digestibility of the diet and protein. These data suggest that all of our diets support gonad growth, but in terms of consumption, a diet that contains protein levels of 17% and 23% with carbohydrate levels of 50% and 58% are beneficial for S. purpuratus.

Gonad quality of sea urchin Paracentrotus lividus cultured in an offshore pilot-scale trial on the south-east Italian coast

“…It is well known that sea urchin gonad growth mainly depends on dietary regime (Cuesta‐Gomez & Sánchez‐Saavedra, ; Marsh, Powell, & Watts, ), since gonads, specifically nutritive phagocytes, are the main nutrient storage organ (Carboni, Hughes, Atack, Tocher, & Migaud, ; Spirlet, Grosjean, & Jangoux, ; Takagi et al., ; Walker et al., ). In fact, a lipid‐rich diet in P. lividus has been shown to increase GSI by increasing gonad reserve storage (Carboni et al., ), while Strongylocentrotus purpuratus specimens fed high‐carbohydrate diets showed a more efficient use of proteins (Cuesta‐Gomez & Sánchez‐Saavedra, ). Carbohydrates seem to be the preferred source of energy for sea urchins (Hammer et al., ; Marsh et al., ), while proteins are considered the main dietary component responsible for P. lividus somatic growth (Carboni et al., ).…”

Effects of Dietary Protein and Carbohydrate Levels on Gonad Index, Composition, and Color in the Purple Sea Urchin Strongylocentrotus purpuratus

“…; Heflin et al. , ; Cuesta‐Gomez and Sánchez‐Saavedra ). Further, their effects have not been evaluated with regards to characteristics of gonad quality, such as color, in S. purpuratus .…”

“…The purple sea urchin Strongylocentrotus purpuratus from Baja California, Mexico, is an underexploited resource (Palleiro‐Nayar et al. ) that is now considered a target species for aquaculture (Cuesta‐Gomez and Sánchez‐Saavedra , ). The capture of S. purpuratus remains low because their gonads (or “uni” or “roe”) are not always adequate in size or quality, affecting its commercialization (Explorations Unlimited ; Palleiro‐Nayar et al.…”

“…In fact, S. purpuratus has not received much research attention regarding its aquaculture anywhere along the North Pacific Coast from Mexico to Canada (Azad et al. ; Cuesta‐Gomez and Sánchez‐Saavedra , ). Due to the lack of research on S. purpuratus aquaculture and the paucity of studies on the aquaculture of invertebrates other than shrimp (order Decapoda), we decided to perform feeding trials.…”

“…The main goal of this study was to evaluate the effects of various protein and carbohydrate levels on the consumption of food, gonad growth, gonad proximate composition, and gonad color in S. purpuratus . The protein and carbohydrate levels that we used were selected based on evidence of gonad growth in S. purpuratus in a previous study (Cuesta‐Gomez and Sánchez‐Saavedra ).…”