Ammonia is one of the most significant environmental pollutants affecting aquatic animals under culture conditions; however, little is known about ammonia toxicity in marine gastropods. In this study, the effects of different total ammonia concentrations (0.0, 2.5, 5.0, 7.5, and 10.0 mg∙L⁻¹ NH₄Cl) on growth performance, tissue damage, antioxidant capacity, immune function, and body composition were investigated in carnivorous ivory shells (Babylonia areolata) after seven weeks of rearing. The growth performance of ivory shells in the higher ammonia treatments (≥ 5.0 mg∙L⁻¹) was significantly lower than that of the control group (P < 0.05). Significantly higher mortalities were observed in the 7.5 and 10.0 mg∙L⁻¹ ammonia-treated groups than those in the control group (P < 0.05). After ammonia exposure, obvious tissue damage in the gill was observed, whereas almost no differences were observed in the hepatopancreas between the control and ammonia-treated groups. The activities of superoxide dismutase (SOD) and catalase (CAT) in the gill and hepatopancreas decreased with increasing ammonia concentrations. The activities of acid phosphatase (ACP) and alkaline phosphatase (AKP) in the hepatopancreas also significantly decreased when ivory shells were cultured in ammonia (P < 0.05), while these two immune enzymes in the gill reached the highest level in the 2.5 mg∙L⁻¹ ammonia-treated group and decreased with the increase of ammonia concentration. The content of malondialdehyde (MDA) and activities of Na⁺/K⁺-ATPase (NKA), aspartate transaminase (AST), and alanine transaminase (ALT) increased with an increase in ammonia concentration. The amino acid content in the muscle of the ammonia-treated groups was lower than that in the control group, while almost all amino acid content in the hepatopancreas increased first and then decreased. Furthermore, the composition of polyunsaturated fatty acids (PUFAs) (e.g., C22:5n3 in the muscle; C22:6n3 and C20:5n3 in the hepatopancreas) showed an increasing tendency and then a decreasing tendency with an increase in ammonia concentration. Our study suggested that higher ammonia (≥ 5.0 mg∙L⁻¹) not only caused a decrease in growth performance, immune and antioxidant-related enzymes, and an increase in mortality, tissue damage, and extra energy metabolism, but also led to significant changes in the nutritional composition of the ivory shell.

氨是在养殖条件下影响水生动物的最重要的环境污染物之一；然而，人们对海洋腹足动物的氨毒性知之甚少。在本研究中，研究了不同总氨浓度（0.0、2.5、5.0、7.5 和 10.0 mg∙L ^-1 NH ₄ Cl）对生长性能、组织损伤、抗氧化能力、免疫功能和身体成分的影响。饲养七周后的食肉象牙贝壳（Babylonia areolata ）。高氨处理（≥ 5.0 mg∙L ^-1）下象牙贝壳的生长性能显着低于对照组（P < 0.05)。7.5 和 10.0 mg∙L ^-1氨处理组的死亡率明显高于对照组（P  < 0.05）。氨暴露后，在鳃中观察到明显的组织损伤，而在对照组和氨处理组之间的肝胰腺中几乎没有观察到差异。鳃和肝胰腺中超氧化物歧化酶（SOD）和过氧化氢酶（CAT）的活性随着氨浓度的增加而降低。象牙壳在氨水中培养时肝胰腺中酸性磷酸酶（ACP）和碱性磷酸酶（AKP）的活性也显着降低（P  < 0.05），而鳃中这两种免疫酶在2.5 mg∙ L ^-1氨处理组随着氨浓度的增加而降低。丙二醛(MDA)的含量和Na ⁺ /K ⁺ -ATP酶(NKA)、天冬氨酸转氨酶(AST)和丙氨酸转氨酶(ALT)的活性随着氨浓度的增加而增加。氨处理组肌肉中氨基酸含量低于对照组，而肝胰腺中几乎所有氨基酸含量均先升高后降低。此外，多不饱和脂肪酸 (PUFA) 的组成（例如, 肌肉中的 C22:5n3; 肝胰腺中的C22:6n3和C20:5n3)随着氨浓度的增加呈现出先升高后降低的趋势。我们的研究表明，较高的氨（≥ 5.0 mg∙L ^-1）不仅会导致生长性能、免疫和抗氧化相关酶的下降，以及死亡率、组织损伤和额外能量代谢的增加，而且还会导致显着的象牙壳营养成分的变化。