Ramadan Amal M, El-halfawy Magdy M
National Institute of Oceanography and Fisheries, P.O. Box 182, Suez, Egypt.
Pak J Biol Sci. 2007 Sep 15;10(18):3120-5. doi: 10.3923/pjbs.2007.3120.3125.
Four economic fish species were collected monthly from commercial catch land at El-Attaka fish landing (Saurida undosquamis, Rhabdosargus haffara, Nemipterusjaponicus and Liza carinata). Histoligical examination of ovaries of these species indicated the presence of atretic oocytes (oocyte retention) as a natural phenomenon in fishes. Depending on the histological descriptions atretic oocytes may be classified into two main types: a, bursting b, non bursting. In the present study, frequency of degenerating oocytes were affected by the gonad maturation. In the early stages, the frequency is very low. It increased gradually reaching its maximum in spent stage about 50%. There is a significant difference between the atretic oocytes and gonad maturation (p < 0.05). Atresia is also affected by the length of the spawning season (Long or short). All examined ovaries of multiple spawners (S. undosquamis) should atretic oocytes. But in (N. japonicus, R. haffara and L. carinata) about 30 to 35% of the ova show atresia. These species have limited spawning season.
每月从埃尔-阿塔卡鱼码头（商业捕捞地）收集四种经济鱼类（长蛇鲻、哈氏金线鱼、日本金线鱼和棱鲻）。对这些鱼类卵巢的组织学检查表明，存在闭锁卵母细胞（卵母细胞滞留），这是鱼类中的一种自然现象。根据组织学描述，闭锁卵母细胞可分为两种主要类型：a，破裂型；b，非破裂型。在本研究中，退化卵母细胞的频率受性腺成熟的影响。在早期阶段，频率非常低。它逐渐增加，在产后期达到最大值，约为50%。闭锁卵母细胞与性腺成熟之间存在显著差异（p<0.05）。闭锁也受产卵季节长短的影响。所有检查的多次产卵鱼类（长蛇鲻）的卵巢都有闭锁卵母细胞。但在（日本金线鱼、哈氏金线鱼和棱鲻）中，约30%至35%的卵子出现闭锁。这些物种的产卵季节有限。
