A histological survey of the brain development in the sturgeon (Acipenser gueldenstaedtii)

Brain development of the Acipenser gueldenstaedtii (A. gueldenstaedtii) was described from days 1 to 36، post-hatch (dph) in this study. Larvae were euthanized، and serial sections of specimens were examined. Our ontogenical study was determined to concentrate on important parts of the brain containing forebrain، midbrain and hindbrain. The primary observation of the telencephalon was in 1-week-old specimens. The size of the forebrain remained relatively steady and did not demonstrate considerable changes، as compared to the other parts of brain. The diencephalon changes were noticeable in 3-week-old A. gueldenstaedtii. 2 major parts of mesencephalon، (tegmental portion and optic tectum) were detected during 4 weeks of development. As in other chondrosteans، the cerebellum appeared highly developed. Medulla oblongata appeared larger in 1-week-old specimens than in 4-week-old specimens.