野生与养殖黄鳍鲷消化道形态组织结构

采用常规石蜡组织切片的方法对野生和养殖黄鳍鲷(Sparus latus)消化道的形态组织结构进行了比较观察。结果表明,野生和养殖黄鳍鲷的消化道存在一定差异。(1)形态学研究表明,食道粗而短,胃呈V形,分为贲门部、胃体部和幽门部,胃与肠的连接处有4条幽门盲囊,肠道在体腔内迂回两个回折。野生黄鳍鲷牙齿更为坚硬锋利,体腔中脂肪较少,消化道更为粗短。野生和养殖黄鳍鲷的肠道系数分别为0.71±0.03和0.94±0.12。(2)组织学研究表明,食道黏膜上皮由扁平细胞层和杯状细胞层组成,杯状细胞发达。胃黏膜由单层柱状上皮组成,无杯状细胞,贲门部和胃体部胃腺发达。幽门盲囊组织学特征与肠相似,上皮为柱状上皮,其中的杯状细胞少于肠。肠中,前肠杯状细胞最多,中肠次之,后肠最少。直肠杯状细胞多于肠。野生与养殖黄鳍鲷组织学的区别在于,消化道相同部位养殖鱼的杯状细胞多于野生鱼,野生鱼的肌层厚度大于养殖鱼。黄鳍鲷消化道的形态组织结构与其生活环境和食物是相关的。

Morphological and Histological Study on the Digestive Tract of Wild and Cultivated Yellowfin Black Porgy (Sparus latus)

The morphology and histology of the digestive tract of wild and cultivated Yellowfin Black Porgy (Sparus latus) were studied using routine method of paraffin tissue section. The results showed that there were some differences between the two populations. Morphological observations showed that oesophagus was crude and short, and the V-shaped stomach was divided into three portions: cardiac stomach, fundic stomach and pyloric stomach. There were four pyloric caeca, and intestine was detoured two inflections in the body cavity. In wild fish, the teeth were harder and sharper, the fat in the body cavity was less, and the digestive tract was cruder and shorter. The average intestinal coefficients of the wild and cultivated Yellowfin Black Porgy were 0.71±0.03 and 0.94±0.12, respectively. Histological observations showed that mucous epithelium of oesophagus was composed of pinacocyte layer and goblet cell layer with rich goblet cells. Stomach had a single-layered columnar epithelium, without goblet cells. The gastric gland was developed in the cardiac stomach and fundic stomach. The histological features of pyloric caeca were similar to those of intestine, with columnar epithelium and less goblet cells. Meanwhile the distribution trend of goblet cells in the whole intestine was: foregut > midgut > hindgut and cultivated fish > wild fish. There were more goblet cells in rectum than in intestine. The major histological differences between wild and cultivated Yellowfin Black Porgy were that there were more goblet cells in the same part of digestive tract in cultivated fish than in wild fish, while the muscular coat was thicker in wild fish than in cultivated fish. It could be concluded that the differences of digestive tract between the two populations relied on their different living conditions and foods.