Uddin Md Jasim, Rahman Md Shamsur, Sonia Saima Sultana, Kubra Sheikh Khadijatul, Mia Md Sujon, Yeasmine Selina
Department of Fisheries Management, Bangladesh Agricultural University, Mymensingh, 2202, Bangladesh.
Freshwater Station, Bangladesh Fisheries Research Institute, Mymensingh, 2201, Bangladesh.
Heliyon. 2024 Mar 26;10(7):e28753. doi: 10.1016/j.heliyon.2024.e28753. eCollection 2024 Apr 15.
The current study aimed to describe the annual gametogenic phenology of the oyster (Röding, 1798) (=), which is found on the west coast of Moheshkhali Island, Cox's Bazar, Bangladesh. Samples were drawn monthly from the intertidal region during low tide, from which 20 adult individuals were selected at random for biometry and histology. The mean condition index (CI), a ratio of tissue wet weight (g) to shell length (cm), varied from 0.58 ± 0.08 to 1.32 ± 0.36. Histology revealed two spawning cycles in the habitat of over the 12 months of the study. Gametogenesis initiated in December and May, and ripe animals principally occurred from July to September and February to May. In the habitat, exhibited two spawning peak periods: April to June and August to October. The undifferentiated stage as a preparatory step for the next spawning extended from November to February for the first spawning cycle and for a brief period in June for the next spawning cycle. The initiation of spawning in March could be associated with the high-level decline of salinity and increased temperature between February and March, in association with the annual rainfall start, whereas the next spawning cycle could be associated with a gradual increase in salinity. No spawning activity was reported from December to February, when the water temperature remained below 22 °C. Further study could be undertaken on the timing of spatfall of in the habitat to harvest spats for commercial farming of this promising species.
本研究旨在描述孟加拉国科克斯巴扎尔莫赫什卡利岛西海岸发现的长牡蛎（Röding，1798年）（=）的年度配子发生物候。在低潮时每月从潮间带区域采集样本，从中随机挑选20个成年个体进行生物测量和组织学研究。平均状况指数（CI），即组织湿重（克）与壳长（厘米）的比值，范围从0.58±0.08到1.32±0.36。组织学研究表明，在为期12个月的研究中，该栖息地的长牡蛎有两个产卵周期。配子发生始于12月和5月，成熟个体主要出现在7月至9月以及2月至5月。在该栖息地，长牡蛎出现两个产卵高峰期：4月至6月和8月至10月。作为下一次产卵准备步骤的未分化阶段，第一个产卵周期从11月持续到2月，下一个产卵周期在6月有一段短暂时间。3月开始产卵可能与2月至3月间盐度大幅下降、温度升高以及年度降雨开始有关，而下一个产卵周期可能与盐度逐渐升高有关。12月至2月期间未观察到产卵活动，此时水温低于22°C。可进一步研究该栖息地长牡蛎的采苗时间，以便为养殖这种有前景的物种收获幼苗。
