Abstract The West Indian top shell Cittarium pica is a gastropod species currently regarded as threatened mainly due to overfishing of wild stocks. Substantial efforts have been invested in the experimental culture of this mollusk for resource conservation, as well for commercial production. In order to determine the suitable culture conditions for this species, the present study addressed the effect of diet and water quality on the energetic physiology of C. pica. Experimental animals were fed with different diets (fresh seaweed, benthic microalgae and artificial biofilm), and exposed to different rates of water renewal (10, 50, 100 and 300% h−1), and levels of salinity (25, 30, 35 and 40 ppt), temperature (22, 27 and 32 °C) and ammonia concentration (2.5, 8.0, 20.0 and 40.0 μg NH3-N L−1). Under such conditions, individual measurements of ingestion rate (IR), absorption efficiency (AE), oxygen consumption rate (OCR), ammonium excretion rate (UR), mucus production rate (MR) and scope for growth (SFG), were conducted. Both, juveniles and adults exhibited a micro-grazing feeding behavior. IR was affected by diet, water renewal and salinity, while AE was influenced by all the factors tested. OCR was only affected by ammonia concentration, while UR was influenced by salinity, temperature and ammonia concentration. Finally, MR was affected by all the factors tested, except for diet. The highest SFG performances were obtained when top shells were fed artificial diet biofilm, and maintained at relatively high levels of salinity (35–40 ppt) and temperature (27–32 °C), and intermediate rates of water renewal (50–100% h−1), oxygen saturation (> 70%) and ammonia concentration (2.5–40.0 μg NH3-N L−1). In general, such responses were associated with high IR and/or AE values, while energy losses in terms of OCR, MR and UR did not show a significant influence.

中文翻译：

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饮食和水质对西印度顶级贝壳 Cittarium pica 能量生理的影响

摘要 西印度顶壳 Cittarium pica 是一种腹足类动物，目前被认为主要由于过度捕捞野生种群而受到威胁。为了资源保护和商业生产，已经在这种软体动物的实验培养中投入了大量努力。为了确定适合该物种的养殖条件，本研究探讨了饮食和水质对异食癖能量生理机能的影响。实验动物饲喂不同的饮食（新鲜海藻、底栖微藻和人工生物膜），并暴露于不同的水更新率（10、50、100 和 300% h-1）和盐度水平（25、30、35和 40 ppt）、温度（22、27 和 32 °C）和氨浓度（2.5、8.0、20.0 和 40.0 μg NH3-N L-1）。在这样的条件下，对摄取率 (IR)、吸收效率 (AE)、耗氧率 (OCR)、氨排泄率 (UR)、粘液产生率 (MR) 和生长范围 (SFG) 进行了单独测量。幼鱼和成鱼都表现出微放牧进食行为。IR 受饮食、水分更新和盐度的影响，而 AE 受所有测试因素的影响。OCR 仅受氨浓度影响，而 UR 受盐度、温度和氨浓度影响。最后，MR 受所有测试因素的影响，但饮食除外。当上层贝壳喂食人工饲料生物膜时，SFG 性能最高，并保持在相对较高的盐度（35-40 ppt）和温度（27-32 °C），以及中等水更新率（50-100%） h−1), 氧饱和度 (> 70%) 和氨浓度 (2.5–40.0 μg NH3-N L-1)。一般而言，此类响应与高 IR 和/或 AE 值相关，而 OCR、MR 和 UR 方面的能量损失并未显示出显着影响。