تعداد ميكروپيل در تخمك مولدين تاس ماهي روسي (Acipenser gueldenstaedtii) صيد شده در سواحل جنوب غربي درياي خزر

Study on ovum micropyle of Russian sturgeon broodfishes (Acipenser gueldenstaedtii) captured in the west- south coast of Caspian Sea

Russian sturgeon {Acipenser gueldenstaedtii (Brandt & Ratzeberg, 1833)) is one of the most valuable fishes of the Caspian Sea, which occur more frequently in the Northern part of the Sea. The number of micropyle in the ovum of Russian sturgeon was investigated in this study. Fifty samples of ovum were fixed in 4% formalin, then animal and plant poles were cut and separated by thorn, washed and at last the number of micropyles were counted and compared in the examined samples. The results of studying 250 ovums showed that minimum, maximum and average number of micropyle in ovums was 0, 13 and 6.1±2.6, respectively. Statistical study indicated significant differences among5 brood fishes (P<0.5).