Fish farming is becoming an increasingly popular agricultural activity, and water quality in these environments is a major concern. Fish parasites, such as monogeneans, respond to changes in abiotic conditions, either with an increase or decrease in population. This study aimed to identify gill monogeneans and analyse their relationships with abiotic factors during the ontogenetic development of Nile tilapia over the fish culture cycle in Mato Grosso do Sul, Brazil. Fish were sampled monthly for eight months, and a total of 200 fish were collected. The physical and chemical water parameters were measured and correlated with the abundance of each monogenean species. Over the fish culture cycle, the physical and chemical parameters fluctuated, and the water quality decreased. The parasites found included Cichlidogyrus tilapiae, Cichlidogyrus thurstonae, Cichlidogyrus sclerosus, Cichlidogyrus halli and Scutogyrus longicornis. The abundances of all species showed significant differences during ontogenetic development (body size) and C. tilapiae, C. sclerosus, C. thurstonae and S. longicornis were correlated with changes in abiotic conditions. However, C. halli was not significantly correlated with any of the evaluated physical or chemical parameters. Understanding how different monogenean species respond to changes in the physical and chemical parameters of water during a production cycle can prevent peaks in abundance and subsequent sanitary problems.

中文翻译：

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罗非鱼养殖中单基因物种对非生物参数变化的响应

养鱼正在成为一种越来越受欢迎的农业活动，这些环境中的水质是一个主要问题。鱼类寄生虫，如单基因动物，会对非生物条件的变化做出反应，无论是种群数量的增加还是减少。本研究旨在在巴西南马托格罗索州的鱼类养殖周期中识别尼罗罗非鱼个体发育过程中的鳃单基因并分析它们与非生物因素的关系。八个月内每月对鱼进行采样，共收集到 200 条鱼。测量了水的物理和化学参数，并与每个单基因物种的丰度相关联。在养鱼周期中，理化参数波动，水质下降。发现的寄生虫包括罗非鱼,Cichlidogyrus thurstonae,Cichlidogyrus sclerosus,大丽鱼和Scutogyrus longicornis。所有物种的丰度在个体发育发育（体型）和罗非鱼,C. 硬化,C. thurstonae和长角链球菌与非生物条件的变化相关。然而，C.哈利与任何评估的物理或化学参数没有显着相关性。了解不同的单基因物种如何在生产周期中对水的物理和化学参数的变化作出反应，可以防止丰度高峰和随后的卫生问题。