濒危鱼类稀有白甲鱼外周血细胞特征

为了研究濒危鱼类稀有白甲鱼（Onychostoma rara）外周血细胞的特征，以采自长江中游沅江水系清水江共计21尾稀有白甲鱼的血液为材料，采用常规方法对稀有白甲鱼外周血细胞的组成、形态、大小和数量进行了观测。结果显示，稀有白甲鱼红细胞数量为（1.75±0.44）×106 个/ L，白细胞数量为（4.91±1.95）×105 个/ L。在血涂片上共计观察到了5种白细胞，包括淋巴细胞、血栓细胞、单核细胞、嗜中性粒细胞和嗜酸性粒细胞，没有发现嗜碱性粒细胞。其5种白细胞数量比例差异较大，其数量比例关系为：淋巴细胞>血栓细胞>嗜中性粒细胞>单核细胞>嗜酸性粒细胞。这5种白细胞的大小也有所不同，其大小关系为：单核细胞>嗜中性粒细胞>嗜酸性粒细胞>淋巴细胞>血栓细胞。与已报道的鱼类相比，稀有白甲鱼白细胞的数量明显较高，红细胞数量较多、体积相对较小，可能与其适应流水生活相关。

Characteristics of Peripheral Hematocytes in Endangered Fish Onychostoma rara

To study the characteristics of the peripheral hematocytes in the endangered fish Onychostoma rara, the hematocytes of the species were inspected, classified and counted, with the routine methods based on the blood samples of 21 individuals of O. rara collected from the Qingshui River (in the Yuanjiang River system located in the middle Yangtze River), Guizhou, China. The results showed that the erythrocytes as well as five types of leukocytes, including lymphocytes, thrombocyte, monocytes, neutrophils and eosinophils, were detected on the Wright-Giemsa's stained smears of peripheral blood in O. rara. The counts of erythrocyte and leukocyte in the blood of the species were (1.75±0.44)×106 cells/L and (4.91±1.95)×105 cells/L respectively. Also, The microscopic characetristics of peripheral hematocytes in the blood smears was recorded, and the long and short diameters of the blood cells were measured and the quantity proportion of each type of the leukocytes in total leukocytes was calculated respectively. The five types of leukocytes were much different from one another in quantity proportion and cell size in O. rara. The quantity proportions of the five types of leukocytes in the blood were: lymphocytes > thrombocyte > neutrophils > monocytes > eosinophils, and the sizes of them were: monocytes > neutrophils > eosinophils > lymphocytes > thrombocyte. The leukocyte count of O. rara was much more than that of most of the other fishes studied, and the erythrocyte was abundant and small in the blood of the species, which is probably the results of adaption of the species to the river environment.