Investigations on trophic requirements of different life cycle stages of Paracentrotus lividus are crucial for the comprehension of species ecology and for its artificial rearing. The future success of echinoculture depends heavily on the development of suitable and cost-effective diets that are specifically designed to maximize somatic growth during the early life stages and gonadal production in the later stages. In this context, a considerable number of studies have recommended animal sources as supplements in sea urchin diets. However, with the exception of Fernandez and Boudouresque (2000), no studies have investigated the dietary requirements over the different life stages of the sea urchin. In the present study, the growth and nutrition of three life stages of P. lividus (juveniles: 15-25 mm; subadults: 25-35 mm; adults: 45-55 mm) were analyzed over a 4-month rearing experiment. Three experimental diets, with 0%, 20% and 40% of animal sourced enrichments, were tested in parallel in sea urchin three size classes. The food conversion ratio, somatic and gonadal growth were assessed in each condition in order to evaluate the optimal level of animal-sourced supplements for each life stage. A general growth model covering the full post-metamorphic P. lividus life cycle was defined for each condition. During the juvenile stage P. lividus requires higher animal supply (40%), while a feeding requirement shift takes place toward lower animal supply (20%) in sub-adult and adult stages. Our results evidenced that the progressive increase in size after the metamorphosis led to a consequent variation of trophic requirements and food energy allocation in the sea urchin P. lividus. Macronutrient requirements varied widely during the different life stages, in response to changes in the energy allocation from somatic growth to reproductive investment. This study sheds light on P. lividus trophic ecology, broadening our basic knowledge of the dietary requirements of juveniles, sub-adults and adults as a function of their behavior also in the natural environment.

不同生命周期阶段的营养需求调查青斑鱼对于理解物种生态学及其人工饲养至关重要。棘鱼养殖未来的成功在很大程度上取决于开发合适且具有成本效益的饮食，这些饮食专门设计用于最大限度地提高生命早期阶段的体细胞生长和后期阶段的性腺生产。在这种情况下，相当多的研究建议将动物来源作为海胆饮食的补充剂。然而，除了 Fernandez 和 Boudouresque (2000)，没有研究调查过海胆不同生命阶段的饮食需求。在本研究中，三个生命阶段的生长和营养P. lividus（幼体：15-25 毫米；亚成体：25-35 毫米；成体：45-55 毫米）在 4 个月的饲养实验中进行了分析。三种实验日粮，分别含有 0%、20% 和 40% 的动物源浓缩物，在三个大小等级的海胆中同时进行了测试。在每种情况下评估食物转化率、体细胞和性腺生长，以评估每个生命阶段动物源性补充剂的最佳水平。涵盖整个后变质的一般增长模型P. lividus为每个条件定义了生命周期。在少年阶段P. lividus需要更高的动物供应量（40%），而在亚成年期和成年期，喂养需求向更低的动物供应量（20%）转变。我们的研究结果表明，变态后体型的逐渐增加导致海胆的营养需求和食物能量分配发生变化P. lividus. 在不同的生命阶段，宏量营养素的需求差异很大，以响应从体细胞生长到生殖投资的能量分配变化。这项研究揭示了P. lividus营养生态学，拓宽了我们对青少年、亚成人和成人饮食需求的基本知识，作为他们在自然环境中的行为的函数。