ABSTRACT: Macroscopic assessments of maturity from whole fish gonads are well established and routinely used in fisheries research and are important in the estimation of size-at-maturity and the impacts of size-selective fishing. Histological assessment of maturity is more accurate, but much slower, more expensive, and so less frequently conducted. We made a comparison between macroscopic and histological maturity classifications for a diandric protogynous hermaphrodite, blue cod Parapercis colias. The agreement between macroscopic and histological maturity classifications was low. Female and male L₅₀ (length at which 50% of the fish are mature) was estimated from histological data as 23 and 26 cm, respectively. Female spawning frequency was 4.6 d, and mean ± SD relative batch fecundity was 6.5 ± 3.3 hydrated oocytes per gram body weight. A single gonad with both testicular and ovarian tissue was found. Many blue cod were assigned incorrect maturity classifications. These results warrant a study of early gonadal development in blue cod to elucidate if and how sex change takes place. Difficulties in determination of sex and maturity may be most pronounced for species, like blue cod, that have complex maturation patterns. For blue cod, a review of the macroscopic maturity classification key and more thorough technician training are called for.

中文翻译：

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评估蓝鳕鱼副产大肠杆菌的成熟度，繁殖力和雌雄同体

摘要：对全鱼性腺成熟度的宏观评估已得到很好的建立，并在渔业研究中被常规使用，对评估成熟度和选择性捕捞的影响非常重要。成熟度的组织学评估更为准确，但速度较慢，成本较高，且执行频率较低。我们做了一个diandric雌性先熟的雌雄同体的宏观和组织学分类的成熟度之间的比较，蓝鳕鱼Parapercis豆粉蝶属。宏观和组织学成熟度分类之间的一致性很低。男女L ₅₀（长度为50 ％根据组织学数据，鱼的成熟度估计为23 cm和26 cm。雌性产卵频率为4.6 d，平均±SD相对分批繁殖力为每克体重6.5±3.3个水合卵母细胞。发现了一个同时具有睾丸和卵巢组织的性腺。许多蓝色鳕鱼被指定了不正确的成熟度分类。这些结果值得对蓝鳕鱼的早期性腺发育进行研究，以阐明是否以及如何发生性别变化。对于具有复杂成熟模式的物种（如蓝鳕鱼）而言，最难确定性别和成熟度。对于蓝鳕鱼，需要对宏观成熟度分类关键字进行审查并进行更彻底的技术培训。