摘要
近年来,广东贺江暴发了由等足类寄生虫引起的严重的鱼类外寄生虫病,给当地网箱养殖和野生鱼类资源造成了严重危害。根据虫体的口器、触角、腹肢等形态学特征将其鉴定为等足目(Isopoda)、扇肢亚目(Flabellifera)、纺锤水虱科(Aegidae)、海弯水虱属(Alitropus)的典型海弯水虱(Alitropus typus)。为了弄清典型海弯水虱对贺江内野生鱼类资源的危害及其种群季节动态变化规律,作者从2006年5月份到2007年4月份,用刺网定时定点捕获野生鲮鱼(Cirrhina molitorella),检查典型海弯水虱的寄生状况。结果发现:典型海弯水虱对鲮鱼的感染率、感染强度和平均密度均从2006年5月份开始上升,至7月份达到高峰,然后逐渐下降,于次年的2月份达到最低点,从3月份开始有所回升。典型海弯水虱种群在不同月份及不同体长鲮鱼中均为聚集性分布,且聚集强度随着平均密度的增加而增加。典型海弯水虱种群在鲮鱼中的感染参数与水温呈显著的正相关,而与宿主的体长无明显的相关性。周年种群结构动态变化分析表明:典型海弯水虱1年只繁殖1次,繁殖受水温的影响,6、7月份是其繁殖高峰期。
In recent years, fish disease outbreaks caused by an ectoparasite have occurred in the He River in Guangdong, China, posing severe threats to beth cage-fanned and wild fish. The parasite was identified as Alitropus typus that belongs to the genus Alitropus （Aegidae, Flabellifera, Isopoda） based on its morphological features （i.e. gnathite, tentacle and pleopods）. In order to assess the negative impacts of A. typus on wild fisheries, a number of mud carp Cirrhina molitorella were sampled by gill net placed at the same location during the period May 2006 to April 2007. Results indicated that infectivity （prevalence, mean infection intensity and mean density of the parasites） on mud carp increased from May and peaked in July, then gradually declined to the lowest point, during February the following year. Infectivity began to increase in March. The parasites showed an aggregate distribution on fish regardless of season and size of the host. The degree of aggregation increased with the increase of mean density of the parasite. Infection rate, mean infection intensity and Mean density were markedly correlated with water temperature, but not with body length of the host. Results of the seasonal population structure dynamics indicated that A. typus propagated once a year. Propagation was influenced by water temperature, and the peak season of propagation was in June and July .
出处
《动物学报》
SCIE
CAS
CSCD
北大核心
2008年第3期407-415,共9页
ACTA ZOOLOGICA SINICA
基金
广东省科技计划项目(No.2005A20401002)~~
关键词
典型海弯水虱
鲮鱼
贺江
种群动态
Isopod, Alitropus typus, Mud carp, Cirrhina molitorella, He River, Population dynamics
