The in vitro efficacy of the essential oil of Piper callosum, Piper hispidum and Piper marginatum against monogeneans and the tolerance of Colossoma macropomum to these oils was assessed. Concentrations of these essential oils were tested, and two control groups were used: one with water from the cultivation tank only and the other with water from the cultivation tank + 70% alcohol, the solvent for these essential oils. For all the concentrations of P. callosum, 100% efficacy against Anacanthorus spathulatus, Notozothecium janauachensis, Mymarothecium boegeri and Linguadactyloides brinkmanni occurred after 5 min of exposure. At concentrations of 600 and 800 mg/L of P. hispidum, 100% in vitro efficacy occurred after 20 min of exposure. At concentrations of 200, 300 and 400 mg/L of P. marginatum, 100% efficacy occurred after 1 h of exposure. In the control groups using water from the tank + alcohol, the total immobilization of the monogeneans varied, while in the control groups with water from the cultivation tank, the total immobilization of monogeneans only occurred after 9 h of exposure. Little structural damage to the tegument of the parasites exposed to P. callosum, P. hispidum and P. marginatum was observed on scanning electron microscopy. The tolerance of C. macropomum for P. callosum, P. hispidum and P. marginatum was assessed and discussed. The results suggest that the essential oils of P. callosum, P. hispidum and P. marginatum possess high in vitro efficacy against monogeneans of C. macropomum and thus require testing in therapeutant baths for use in aquaculture.

中文翻译：

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Piper callosum、Piper hispidum 和 Piper marginatum (Piperaceae) 的精油对 Colossoma macropomum (tambaqui) 的单系植物具有体外功效

评估了胼胝、Piper hispidum和Piper marginatum 的精油对单殖吸虫的体外功效以及Colossoma macropomum对这些油的耐受性。测试了这些精油的浓度，并使用了两个对照组：一组仅使用来自栽培槽的水，另一组使用来自栽培槽的水 + 70% 酒精，这些精油的溶剂。对于P 的所有浓度。 胼胝, 100% 有效对抗Anacanthorus spathulatus , Notozothecium janauachensis , Mymarothecium boegeri和Lingguadactyloides brinkmanni在暴露 5 分钟后发生。在 600 和 800 mg/L 的P浓度下。 hispidum，在暴露 20 分钟后发生 100% 的体外功效。在 200、300 和 400 mg/L 的P浓度下。 marginatum，暴露 1 小时后发生 100% 的疗效。在使用水箱水+酒精的对照组中，单殖酵母的总固定化不同，而在使用培养箱水的对照组中，单殖酵母的完全固定化仅在暴露9小时后发生。对暴露于P的寄生虫的外皮几乎没有结构性损坏。 胼胝体，P。 胡桃木和P。 在扫描电子显微镜下观察到边缘。公差Ç。 macropomum为P。 胼胝体，P。 菱形和P . 评估和讨论了marginatum。结果表明，P . 胼胝体，P。 菱形和P . marginatum对C . 大马铃薯 因此需要在用于水产养殖的治疗浴中进行测试。