卵形鲳鲹消化道的形态学、组织学和组织化学

Morphological,histological,and histochemical observation of digestive tract in ovate pompano Trachinotus ovatus

采用形态解剖、组织学和组织化学方法,研究了卵形鲳鲹Trachinotus ovatus消化道结构的特点。结果表明:卵形鲳鲹口咽腔较小,上下唇有许多绒毛状突起;上下颌无齿,鳃耙内侧具有绒毛状细齿,口咽腔具有多种类型齿;食道粗短,内表面分布有许多较为宽大的黏膜褶;胃呈"U"形,盲囊部明显,贲门部和盲囊部具有丰富的胃小凹和胃腺;前、中、后肠黏膜褶丰富,后肠黏液细胞密度最大,肠长比为0.61;幽门盲囊细长,有25～35条。消化腺为肝胰脏。食道以Ⅰ型黏液细胞为主,贲门部以Ⅰ型和Ⅲ型黏液细胞为主,盲囊部、幽门部、前肠、中肠和幽门盲囊以Ⅲ型黏液细胞为主,后肠以Ⅱ型黏液细胞为主。

The morphological,histological and histochemical characteristics of digestive tract were studied in ovate pompano Trachinotus ovatus by dissection,histology and histochemistry with H.E and AB-PAS.Results showed that the fish had smaller oropharynx with numerous teeth.Many villius-like extrusions were found on the upper and lower lips,no tooth existing on the maxilla and lower jaws.The villus-like extrusions were observed on the inner side of the gill rakers.Esophagus was thick and short with many broad mucosa rugas.The stomach was expanded and shaped as U with a distinct cecum,abundance gastric pits and gastric gland in cardiac portion and in gastric cecum.There were plentiful mucosa rugas on the surface of foregut,midgut and hindgut with the maximum mucous cell density.The pyloric caeca were changed from 25 to 35 in number,and long and thin in shape.The ratio of body length to intestine length was 0.61.Hepatopancreas was of the digestive gland.Most of mucous cells in esophagus were of type Ⅰ while the type Ⅰ and type Ⅲ predominated in cardiac portion.Most mucous cells in gastric cecum,pyloric portion,foregut,midgut and pyloric caeca were of type Ⅲ colour,and the type Ⅱwere in the hindgut.