Dero digitata is the definitive oligochaete host of Henneguya ictaluri (Cnidaria: Myxobolidae), the causative agent of proliferative gill disease in U.S. farm-raised Channel Catfish Ictalurus punctatus and hybrid catfish (Channel Catfish × Blue Catfish I. furcatus). Several studies were performed to identify optimal conditions for culturing D. digitata in the laboratory for experimental life cycle studies. The first experiments investigated the effects of temperature on D. digitata population growth. Five different growth studies were conducted, each consisting of three different temperature treatments ranging from 7°C to 32°C. Cultures were held under different temperature regimes, and D. digitata numbers were determined after 2 weeks. Dero digitata populations reared at 21–32°C had significantly higher population growth than those maintained at lower temperatures. Additional experiments investigated the effects of supplemental diets on laboratory-reared D. digitata populations. Treatments consisted of autoclaved water that was collected from production ponds with substantial algal growth or a reservoir pond with a negligible algal bloom and maintained at ideal temperatures determined from the temperature trials (~26°C). Cultures were supplemented with three different commercially available feeds designed for bottom-feeding ornamental fish. Significantly larger numbers and greater reproductive rates, taken as an indirect measure of population fitness, were observed in D. digitata cultured in autoclaved pond water supplemented with algal wafers containing 29.0% minimum (min.) crude protein, 7.0% min. crude fat, 6.0% maximum (max.) crude fiber, 9.0% max. moisture, and 0.8% min. phosphorus. A final experiment showed that weekly water exchanges resulted in greater population growth of D. digitata relative to culture in nonexchanged water. This work optimizes the laboratory propagation of D. digitata and will facilitate life cycle studies and controlled experiments establishing developmental timelines and host–parasite interactions of H. ictaluri, similar to other myxozoan parasites.

中文翻译：

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温度调节和饲料补充显着改善了实验室饲养的指趾蟾（Annelida：Naididae）的种群增长

Dero digitata是Henneguya ictaluri (Cnidaria: Myxobolidae)的最终寡毛类宿主，它是美国养殖的海峡鲶鱼Ictalurus punctatus和杂交鲶鱼 (Channel Catfish × Blue Catfish I. furcatus )增殖性鳃病的病原体。进行了几项研究，以确定在实验室中培养D. digitata 的最佳条件，以进行实验生命周期研究。第一个实验研究了温度对D. digitata种群增长的影响。进行了五项不同的生长研究，每项研究由三种不同的温度处理组成，范围从 7°C 到 32°C。在不同的温度条件下进行培养，并且D. 2 周后确定digitata数量。在 21-32°C 下饲养的Dero digitata种群的种群增长率明显高于在较低温度下饲养的种群。其他实验研究了补充饮食对实验室饲养的D. digitata 的影响人口。处理包括从藻类大量生长的生产池塘或藻华可忽略不计的水库池塘收集的高压灭菌水，并保持在温度试验确定的理想温度（~26°C）。培养物中添加了三种不同的市售饲料，这些饲料专为底栖观赏鱼而设计。在D. digitata中观察到显着更大的数量和更高的繁殖率，作为种群适应性的间接测量在高压灭菌的池塘水中培养，并辅以含有 29.0% 最低（最低）粗蛋白、7.0% 最低含量的藻片。粗脂肪，最多 6.0%（最大）粗纤维，最多 9.0%。水分，和 0.8% min。磷。最后的实验表明，与在未交换的水中培养相比，每周换水导致D. digitata 的种群增长更大。这项工作优化了D. digitata的实验室繁殖，并将促进生命周期研究和控制实验，以确定H. ictaluri 的发育时间表和宿主 - 寄生虫相互作用，类似于其他粘液动物寄生虫。