Cassel Mônica, Chehade Chayrra, Souza Branco Giovana, Caneppele Danilo, Romagosa Elizabeth, Borella Maria Inês
Fish Endocrinology Laboratory, Department of Cell and Developmental Biology, Institute of Biomedical Sciences, University of Sao Paulo, Av. Prof Lineu Prestes n. 1524, lab 426, CEP 05508-000, Sao Paulo, SP, Brazil.
Fish Endocrinology Laboratory, Department of Cell and Developmental Biology, Institute of Biomedical Sciences, University of Sao Paulo, Av. Prof Lineu Prestes n. 1524, lab 426, CEP 05508-000, Sao Paulo, SP, Brazil.
Theriogenology. 2017 Aug;98:1-15. doi: 10.1016/j.theriogenology.2017.04.044. Epub 2017 Apr 28.
Astyanax altiparanae is a Brazilian species of substantial commercial, environmental and scientific importance; however, existing studies on its reproduction do not seem to provide enough details. In light of the increasing use of this species in fish farming and the need for basic studies for the development of new production technologies, we describe the structural and ultrastructural characteristics of the ovaries of A. altiparanae, and characterize the species' reproductive cycle. Females were collected monthly from March 2013 to February 2014, and reproductive management began in October 2013. The ovaries were removed, fixed in Karnovsky's fixative, and prepared for light microscopy, transmission electron microscopy and immunohistochemistry anti-PCNA. These techniques enabled us to characterize the ovaries, the germ cells, and the somatic cells in detail, as well as their changes over time. The reproductive cycle was characterized based on the monthly variation in the gonadosomatic ratio, the proportion of germ cells, and the rate of oogonium proliferation. The macroscopic analysis of the ovaries suggests that the vascularization pattern and color of the ovaries vary according to development. There are new types of analyses that can be applied even in the fish farming industry, such as a comparison between ovaries staining and weight or the frequency distribution of these colors throughout the year. This study also provides details on microscopic characteristics that have never before been reported for species of Astyanax, such as the presence of annulate lamellae in oogonia, the development of the zona pellucida from oocytes in the one-nucleolus step, and the development of the micropylar apparatus in oocytes in the cortical alveolar step. When the reproductive cycle was analyzed, this species was found to have a long period of spawning, with a reproductive peak from October to February and multiple spawning events, confirming the period already described in the literature. Variations in reproductive periods and the ability to reproduce in lentic environments suggest that A. altiparanae has the ability to respond quickly to environmental changes and exhibits high reproductive flexibility. All of these characteristics confirm the great potential of this species in the fish farming industry.
高身副脂鲤是一种在巴西具有重大商业、环境和科学价值的物种；然而，现有的关于其繁殖的研究似乎并未提供足够的细节。鉴于该物种在养鱼业中的使用日益增加，以及开发新生产技术所需的基础研究，我们描述了高身副脂鲤卵巢的结构和超微结构特征，并对该物种的繁殖周期进行了特征描述。从2013年3月至2014年2月每月采集雌性个体，并于2013年10月开始进行繁殖管理。取出卵巢后，用卡诺氏固定液固定，并准备用于光学显微镜、透射电子显微镜和抗增殖细胞核抗原免疫组织化学分析。这些技术使我们能够详细描述卵巢、生殖细胞和体细胞，以及它们随时间的变化。根据性腺指数的月度变化、生殖细胞比例和卵原细胞增殖率来表征繁殖周期。对卵巢的宏观分析表明，卵巢的血管化模式和颜色会根据发育情况而变化。甚至在养鱼业中也可以应用一些新型分析方法，例如卵巢染色与重量之间的比较或这些颜色全年的频率分布。本研究还提供了关于高身副脂鲤物种此前从未报道过的微观特征的详细信息，例如卵原细胞中环形片层的存在、单核期卵母细胞透明带的发育，以及皮质泡期卵母细胞微孔装置的发育。在分析繁殖周期时，发现该物种产卵期较长，繁殖高峰期为10月至2月，且有多次产卵事件，这证实了文献中已描述的时期。繁殖期的变化以及在静水环境中繁殖的能力表明，高身副脂鲤有能力快速响应环境变化，并表现出高度的繁殖灵活性。所有这些特征都证实了该物种在养鱼业中的巨大潜力。
