鳙鳃上台湾棘带吸虫囊蚴的感染

从1993年8月到1994年11月，对感染台湾棘带吸虫囊蚴的鳙鳃丝、鳃耙进行了为期16个月的调查研究表明鳃丝、鳃耙的感染率范围为0-100%(83.33±25.47%)、(61.13±44.45%)，感染强度范围分别为0-109.15(54.89±34.09)、0-125.57(41.18±49.34)，囊蚴的平均密度范围分别为0-97.76(46.94±26.25)，0-125.57(40.61±49.71)；当鳙体长小于90mm时，鳃丝、鳃耙的感染率、感染强度、囊蚴的平均密度随着其体长的增大而增长；当体长大于90mm时，三项指标随着其体长的增大具有减小的趋势，其中鳃耙的变化规律明显；当体长大于141.7mm时，鳃耙的感染率、感染强度、囊蚴的平均密度都为0；随着鳙的生长，鳃丝囊蚴所占的比例逐渐增大，从0增加到100%，而鳃耙囊蚴所占的比例逐渐减小，从100%下降到0。

INFECTION OF THE METACERCARIAL CYSTS OF THE DIGENEAN,CENTROCESTUS FORMOSANUS ON THE GILLS OF ARISTCHTHYS NOBILIS

The present paper deals with the infection of the metacercarial cysts of Centrocestus formosanus on the gill filaments and gill rakers of Aristchthys nobilis from August 1993 to November 1994. The results indicated that the prevalence of the gill filaments and gill rakers ranged from 0 to 100%. The mean infections intensity of the gill filaments and gill raters varied from 0 to 109.15 and 0 to 125.57, respectively. The relative density or abundance of the metacercarial cysts on the gill filaments and gill rakers was 0 to 97.76 and 0 to 125. 57 respectively. The preavlence, mean intensity and the relative density of the metacercarial cysts on the gill filaments and gill rakers increased with the growth of the host Aristchthys nobilis when the body length was less than 90 mm, declined when the body length of the host exceeded 90 mm, which on the gill rakers changed obviously. No metacercarial cysts occurred on the gill rakers when the body length of the host exceeded 141.7mm. The metacercarial cysts percentage of the gill filaments increased from 0 to 100% with the growth of the host, but those of the gill rakers declined from 100% to 0 with the growth of the host.