Many organizations have suggested the use of the Calanoid copepod Acartia tonsa in protocols for acute toxicity tests. Nevertheless, these protocols present some problems, such as using 60–180 µm meshes to separate specific stages of A. tonsa or carrying out the tests using small volumes that reflect high densities of A. tonsa that do not occur in nature, which could lead to distorted results. In addition, ecotoxicological studies may use statistical approaches that are inadequate for the type of data being analysed. For these reasons, some methodological approaches for bioassays using A. tonsa need to be clarified and revised. In this study, we present information about (i) the retention of copepodite stages of A. tonsa on 180, 330 and 500 µm net meshes; (ii) tested storage volumes of 1 organism per 5, 10 or 20 mL in each test container (TC); and (iii) considerations about the statistics employed. The results demonstrated that a net mesh of 180 µm is capable of retaining all copepodite stages (CI to CVI), contrasting with the recommendation of using a 180 µm mesh to separate out adults only. Coarser meshes (330 and 500 µm) can also retain different proportions of all copepodite stages, but cannot separate out one developmental stage only. Twenty-five millilitres of medium in an open TC, commonly employed in bioassays simulating densities of 1 organism 5 mL⁻¹, completely evaporated, and the results showed that the TCs need to be covered (e.g., PVC film) and filled with a minimum of 100 mL of culture medium (simulating densities of 1 organism 20 mL⁻¹) to avoid evaporation and increases in salinity. The current use of ANOVA in ecotoxicological studies with proportions of surviving organisms should also be reconsidered since the data are discrete and have a binomial distribution; general linear models (GLMs) are considered more adequate. The information presented here suggests some adjustments that hopefully will enable the improvement of the procedures and methods employed in studies of acute toxicity using the copepod A. tonsa.

许多组织建议在急性毒性试验的方案中使用Calanoid pe足类A螨。但是，这些协议仍然存在一些问题，例如使用60–180 µm的网格来分离扁桃体的特定阶段，或者使用反映自然界中不存在的高密度的扁桃体的小体积来进行测试。结果失真。此外，生态毒理学研究可能会使用不足以用于所分析数据类型的统计方法。由于这些原因，需要澄清和修订一些使用扁桃体进行生物测定的方法学方法。在这项研究中，我们介绍有关（i）的信息在180、330和500 µm的网眼上保留了A.tonsa的角足类阶段；（ii）在每个测试容器（TC）中每5、10或20毫升测试的1种生物体的存储量；（iii）有关所用统计资料的考量。结果表明，与建议仅使用180 µm筛网分离成年动物的建议相比，180 µm的筛网能够保留所有的角砾岩阶段（CI至CVI）。粗筛网（330和500 µm）也可以保留所有坡足石阶段的不同比例，但不能仅分离出一个发育阶段。在开放式TC中的25毫升培养基，通常用于模拟1种生物体5 mL ^-1的密度的生物测定中，完全蒸发，结果表明，TCs需要覆盖（例如，PVC膜）并至少填充100 mL培养基（模拟1种生物的密度为20 mL ^-1），以避免蒸发和盐度增加。由于数据是离散的并且具有二项式分布，因此还应考虑将ANOVA用于幸存生物比例的生态毒理学研究中的当前用途。一般线性模型（GLM）被认为更合适。此处提供的信息建议进行一些调整，希望可以改进使用pe足拟杆菌A.tonsa进行急性毒性研究的程序和方法。