饥饿对南方鲇仔稚鱼消化系统的形态和组织学影响

EFFECTS OF STARVATION ON MORPHOLOGY AND HISTOLOGY OF DIGESTIVE SYSTEM IN LARVAL AND JUVENILE SILURUS MERIDIONALIS CHEN

在实验室饲养条件下，对南方鲇仔、稚鱼进行饥饿，观察了消化系统的形态和组织学变化。仔鱼肝脏萎缩，肠管缩短、变细，失去弯曲形状。组织学结构与功能明显衰退：肝组织变得疏松，细胞缩小，仔鱼肝细胞内无脂质积累，到饥饿后期，部分细胞核仁解体；稚鱼肝细胞内贮存的脂质迅速消失，细胞由多角形变为圆形。胰脏组织变得致密，腺泡小叶分界不清，腺泡萎缩，其内分泌物减少或消失。消化道上皮细胞的高度下降，微绒毛退化，胃腺不发达，十二指肠及小肠上皮细胞内脂质空泡消失，直肠上皮细胞内嗜酸性颗粒减少。

Morphological and histological changes of Silurus meridionalis larvae and juveniles, raised in laboratory condition, were observed during starvation. Livers of lareae were shrunken; Guts were shorter and thinner, and lost the winding shape.Signs of degeneration in histological structure and function of digestive organs were significant during starvation: Hepatic tissue becam imcompact due to hepatic cells’shrinkage and sinusoids’ expansion. In larvae, no lipids were observed in hepatic cells and in latter period of starvation, parts of nucleoli of hepatic cells disintegrated.Soon after the onset of sforvation in juveniles, the multiangle hepatic cell became round and lost itS lipide saved during feeding days. Pancreatic tissue becam more compact with a continuous starvation. The boundary between acinar lobes was unclear;Acini were shrunken; Zymogen granules secreted by the acini decreased or disappeared.Aftor starvation, the height of epithelial cells of the digestive tract decreased and microvilli deteriorated. Stomach glands were undveloped; The lipid vesicles in epithelial cells of duodenum and small intestine disappeared, and the number of acidophilic particles in epithelial cells of rectum reduced.