Geophagus brasiliensis is a species native from Brazilian continental waters and it is distributed in several aquatic ecosystems. Despite its importance to artisanal fishing, mainly for riverside communities, and fishkeeping, this species is an unusual resource for aquaculture. Fish farming can be carried out in different systems, as in biofloc system (BFT), which has some advantages comparing to traditional semi-intensive systems: high densities, maximizing the use of water and food provided. The objective was to evaluate the rearing of the G. brasiliensis in a BFT comparing with a clean water system (CW), considering the zootechnical performance, water quality and microorganisms community. The experiment lasted 40 days and was carried out in tanks with a useful volume of 200 L, with three repetitions for each treatment. To compare the two systems, the fish conditions (weight-length ratio, condition factor and zootechnical performance) and the conditions of the environment (water quality and composition of microorganisms in the BFT treatment) were evaluated. BFT animals showed higher zootechnical performance (final weight, weight gain and feed conversion) when compared to treatment CW. The water quality showed a difference between BFT and CW for all levels except temperature and N-ammoniacal; however, it was within the acceptable limits for cichlids in the two treatments. Eight rates of microorganisms, potential food for the fish, were found in the BFT treatment during the experiment. The species G. brasiliensis showed a higher zootechnical performance in a biofloc system compared to the clear water system, indicating the potential for cultivation in intensive production systems.

中文翻译：

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生物絮团和清水系统中珍珠慈鲷 Geophagus brasiliensis 的养殖参数评估

Geophagus brasiliensis是一种原产于巴西大陆水域的物种，分布在多个水生生态系统中。尽管它对手工捕鱼（主要是对河边社区）和养鱼很重要，但该物种对于水产养殖来说是一种不寻常的资源。养鱼可以在不同的系统中进行，如生物絮团系统 (BFT)，与传统的半精养系统相比，它具有一些优势：高密度，最大限度地利用水和提供的食物。目的是评估G的饲养情况。巴西人在 BFT 中与清洁水系统 (CW) 进行比较，考虑到畜牧业性能、水质和微生物群落。实验持续 40 天，在有效容积为 200 L 的罐中进行，每个处理重复 3 次。为了比较这两个系统，对鱼的状况（体重-长度比、状况因素和畜牧业性能）和环境状况（水质和 BFT 处理中的微生物组成）进行了评估。与 CW 处理相比，BFT 动物表现出更高的畜牧学性能（最终体重、体重增加和饲料转化率）。除了温度和 N-氨水外，所有水平的水质都显示出 BFT 和 CW 之间的差异；然而，在两种处理中，它都在慈鲷可接受的范围内。在实验过程中，在 BFT 处理中发现了八种微生物，它们是鱼的潜在食物。物种与清水系统相比，G. brasiliensis在生物絮团系统中表现出更高的畜牧学性能，表明在集约化生产系统中培养的潜力。