Fish reproduction in natural environments tends to occur in conditions, including extreme pH values, ideal for the survival of offspring. In this context, the purpose of this study was to assess the influence of pH on both survival and early development of two fish species, Astyanax lacustris (short-distance migrating fish) and Piaractus mesopotamicus (long-distance migrating fish), with different reproductive strategies. Our experiments were divided into two tests (incubation and larviculture) at five pH levels. First was incubation through a water recirculation system using 2 L incubators followed by larviculture using a 2.5 L aquarium. pH had no influence on the hatching rate of A. lacustris eggs, but affected the yolk-sac diameter, while the newly-hatched larvae had some skeletal disorders. For P. mesopotamicus, pH influenced the hatching rate and perivitelline space, while the newly-hatched larvae had several skeletal disorders. The larviculture of A. lacustris revealed no effect on the survival rate, but the analyzed morphometric variables indicated significant differences between the treatments. An acidic pH negatively influenced the survival rate of P. mesopotamicus, and all morphometric variables also varied significantly between the treatments. We concluded that both the survival and development of A. lacustris and P. mesopotamicus revealed different responses at pH levels during incubation and larviculture tests.

中文翻译：

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pH对具有不同繁殖策略的鱼类的孵化和早期发育的影响。

在自然环境中鱼类繁殖往往发生在包括极端pH值在内的条件下，非常适合于后代的生存。在这种情况下，本研究的目的是评估pH对两种具有不同繁殖力的鱼类Astyanax lacustris（短距离迁徙鱼）和Piaractus mesopotamicus（长距离迁徙鱼）的存活和早期发育的影响。策略。我们的实验分为五个pH值下的两个测试（孵育和幼虫培养）。首先是使用2 L培养箱通过水循环系统进行培养，然后使用2.5 L水族馆进行幼虫养殖。pH值对A. lacustris卵的孵化率没有影响，但会影响卵黄囊直径，而新孵化的幼虫则有一些骨骼异常。对于美索不动杆菌，pH影响孵化率和卵白质空间，而新孵化的幼虫有几种骨骼疾病。乳酸菌的幼虫培养对存活率没有影响，但分析的形态计量学变量表明处理之间的显着差异。酸性pH值对美索不动杆菌的存活率产生负面影响，并且所有形态学变量在处理之间也存在显着差异。我们得出的结论是，在孵育和幼虫培养试验中，A。lacustris和P. mesopotamicus的存活和发育都显示出在pH值下的不同响应。但分析的形态计量学变量表明治疗之间的显着差异。酸性pH值对美索不动杆菌的存活率产生负面影响，并且所有形态学变量在处理之间也存在显着差异。我们得出的结论是，在孵育和幼虫培养试验中，A。lacustris和P. mesopotamicus的存活和发育都显示出在pH值下的不同响应。但分析的形态计量学变量表明治疗之间的显着差异。酸性pH值对美索不动杆菌的存活率产生负面影响，并且所有形态计量学变量在处理之间也存在显着差异。我们得出的结论是，在孵育和幼虫培养试验中，A。lacustris和P. mesopotamicus的存活和发育都显示出在pH值下的不同响应。