This work aimed to evaluate the whole weight (g), shell height (mm), mortality (%) and reproductive aspects (condition index and histology) of triploid (3N) Pacific oysters (Crassostrea gigas) cultivated in southern Brazil. To accomplish this, a comparative experiment was performed with a diploid (2N) control group in two cultivation sites on Santa Catarina Island: North Bay (NB) and South Bay (SB). Whole weight, height and cumulative mortality were evaluated monthly for eight months and condition index (CI) for six months. Histological analysis was performed every two weeks for four months to investigate reproductive aspects. At the end of the experiment, whole weight and height were similar for 3N and 2N oysters. However, while more growth in whole weight and height was observed in the initial phase of cultivation in NB, such growth was not detected in SB until intermediate and final grow‐out phase. At harvest, cumulative mortality in 3N oysters was similar that in 2N oysters. The results suggest that diploid and triploid oysters grown in southern Brazil have similar developmental patterns based on whole weight and height, as well as reproductive cycle. In addition, cultivation sites have more influence on growth and mortality than ploidy levels.

中文翻译：

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巴西南部二倍体和三倍体太平洋牡蛎（Crassostrea gigas，THUNBERG，1793年）的生长，死亡率和生殖特性

这项工作旨在评估三倍体（3N）太平洋牡蛎（Crassostrea gigas）的总重量（g），壳高（mm），死亡率（％）和生殖方面（状况指数和组织学））种植在巴西南部。为此，在圣卡塔琳娜岛的两个种植地点：北湾（NB）和南湾（SB）与二倍体（2N）对照组进行了比较实验。每月评估八个月的体重，身高和累积死亡率，六个月评估病情指数（CI）。每两个星期进行组织学分析，持续四个月，以调查生殖方面。在实验结束时，3N和2N牡蛎的总重量和高度相似。然而，尽管在NB的培养初期，整体重量和身高都有增长，但直到中期和最终的成长期才在SB中检测到这种增长。收获时，3N牡蛎的累积死亡率与2N牡蛎相似。结果表明，在巴西南部生长的二倍体和三倍体牡蛎具有基于整个体重和高度以及生殖周期的相似发育模式。此外，栽培场所对生长和死亡率的影响大于倍性水平。