Histological Observations of Some Organs in the Triggerfish, Canthidermis rotundatus, Stranded on the Coast of Niigata Facing the Japan Sea

概要

論文の詳細を見る
The endocrine and internal organs of stranded specimens of the triggerfish, <I>Canthidermis rotundatus</I>, were studied histophysiologically.The specimens of medium size used were stranded on the beach of Niigata facing the Japan Sea.As they were lightly starved, not so severe changes were detected in the digestive tube, exocrine pancreas, kidney, and spleen with the exception of a large amount of fat deposition in the liver.In the endocrine pancreas, i.e., the Brockmann body, three types of cells (A, B, and D cells) were identified.The ovary was crowded with a number of oocytes in the early growth stages, whereas a considerably large portion of the testis was occupied by spermatogonia in addition to a small number of elaborate spermatozoa.The amount of Gomori positive neurosecretory material produced in the cells of the nucleus preopticus varied considerably according to each specimen.On the other hand, moderate amount of this material was deposited in the pars nervosa.The acidophil neurosecretory material stored in the cells of the nucleus lateralis tuberis was scanty.Seven types of glandular cells were demonstrated in the adenohypophysis: among them, the basophils diagnosed as gonadotrophs contained only a small amount of granules.Therefore, it seemed probable that the triggerfish carried by the northward Tsushima Warm Current in winter were the immature fish in the process of abortive migration.
日本魚類学会の論文