Effect of Macroalgae Protein Levels on Some Reproductive Aspects and Physiological Parameters for the Abalone, Haliotis tuberculata coccinea (Reeve 1846)

The effect of food quality on some reproductive aspects (the fatty acid profile and the morphology of the gonad and the fecundity) and physiological parameters (growth and feeding rates) were evaluated in adult abalone, Haliotis tuberculata coccinea, females. Abalones were fed on macroalgae diets, Gracilaria cornea, with three different protein levels, Low‐N, Medium‐N, and High‐N. After inducing spawning, a higher number of eggs released per gram of abalone and the greatest egg and cytoplasm diameters were found in abalones fed on Medium‐N and High‐N G. cornea diets. Feeding High‐N G. cornea increased the level of arachidonic acid (AA, 20:4n‐6) in the mature gonad tissue in H. tuberculata coccinea. Likewise, a histological study on the gonadal morphology revealed that ripe‐stage individuals fed on a Low‐N G. cornea diet had a larger macrophage populations and the areas of degenerated oocytes increased. These results suggest that macroalgae cultivated in seawater enriched with ammonium may be a good choice for producing food for female H. tuberculata coccinea broodstock in the Canaries.