Water quality is essential for successful aquaculture. For freshwater shrimp farming, ammonia concentrations can increase considerably, even when culture water is renewed frequently, consequently increasing the risk of ammonia intoxication. We investigated ammonia lethality (LC₅₀-96 h) in a hololimnetic population of the Amazon River shrimp Macrobrachium amazonicum from the Paraná/Paraguay River basin, including the effects of exposure to 4.93 mg L⁻¹ total ammonia concentration on gill (Na⁺, K⁺)-ATPase activity. The mean LC₅₀-96 h was 49.27 mg L⁻¹ total ammonia, corresponding to 1.8 mg L⁻¹ un-ionized ammonia. Except for NH₄⁺ affinity that increased 2.5-fold, that of the gill (Na⁺, K⁺)-ATPase for ATP, Mg²⁺, Na⁺, K⁺ and ouabain was unchanged after ammonia exposure. Western blotting of gill microsomal preparations from fresh caught shrimps showed a single immunoreactive band of ≈110 kDa, corresponding to the gill (Na⁺, K⁺)-ATPase α-subunit. Ammonia exposure increased (Na⁺, K⁺)-ATPase activity by ≈25%, coincident with an additional 130 kDa α-subunit immunoreactive band, and increased K⁺-stimulated and V(H⁺)-ATPase activities by ≈2.5-fold. Macrobrachium amazonicum from the Paraná/Paraguay River basin is as tolerant to ammonia as are other Amazon River basins populations, showing toxicity comparable to that of marine crustaceans.

水质对于成功的水产养殖至关重要。对于淡水虾养殖，氨浓度会显着增加，即使经常更新养殖水，从而增加氨中毒的风险。我们研究了来自巴拉那/巴拉圭河流域的亚马逊河虾Macrobrachium amazonicum全息种群中的氨致死率 (LC ₅₀ -96 h) ，包括暴露于 4.93 mg L ^-1总氨浓度对鳃 (Na ⁺ , K ⁺ )-ATP酶活性。平均 LC ₅₀ -96 h 为 49.27 mg L ^-1总氨，对应于 1.8 mg L ^-1未电离氨。新罕布什尔州除外₄ ⁺亲和力增加了 2.5 倍，鳃 (Na ⁺ , K ⁺ )-ATP 酶对 ATP、Mg ²⁺、Na ⁺、K ⁺和哇巴因的亲和力在氨暴露后没有变化。来自新鲜捕获的虾的鳃微粒体制剂的蛋白质印迹显示约110 kDa的单个免疫反应带，对应于鳃（Na ⁺，K ⁺）-ATP酶α-亚基。氨暴露使 (Na ⁺ , K ⁺ )-ATPase 活性增加了 ≈25%，与额外的 130 kDa α-亚基免疫反应带一致，并且 K ⁺刺激和 V(H ⁺ )-ATPase 活性增加了 ≈2.5 倍.来自巴拉那/巴拉圭河流域的亚马逊沼虾对氨的耐受性与亚马逊河流域的其他种群一样，其毒性与海洋甲壳类动物相当。