Common forms of atresia in the ovary of some Red Sea fishes during reproductive cycle.
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.
Ramadan
Amal M
AM
National Institute of Oceanography and Fisheries, P.O. Box 182, Suez, Egypt.
El-halfawy
Magdy M
MM
D000818:Animals; D005260:Female; D005399:Fishes; D009865:Oocytes / Q000502:physiology*; D010053:Ovary / Q000002:abnormalities / Q000033:anatomy & histology* / Q000473:pathology; D010587:Phagocytosis; D012098:Reproduction; D013045:Species Specificity