福寿螺休眠期体内广州管圆线虫生长发育及其感染性的观察研究

目的 了解福寿螺处于休眠期对其体内感染的广州管圆线虫幼虫生长发育及其感染性的影响。 方法 来自实验室的广州管圆线虫L1幼虫感染福寿螺，感染后第1 天螺置于25.0～25.5 ℃ 恒温室中休眠，观察体内幼虫生长发育情况，第13天起解剖观察幼虫生长发育情况。感染后第20 天福寿螺置冬季室内自然变温条件下休眠2个月，每隔10 d观察螺体内幼虫活力。检获的L3幼虫经口或腹腔注射感染SD大鼠，观察其感染性。同时观察螺的生存与体重变化情况，并以水族缸饲养螺作平行对照。 结果 25.0～25.5 ℃ 恒温条件下螺休眠不影响体内幼虫发育，且其幼虫发育历期为（16.3±0.6） d，显著快于水族缸饲养螺（17.6±0.96）d（t=5.72，P<0.01）。冬季室内自然变温条件下的休眠螺，生存率高于水族缸饲养螺（P<0.05),体重下降率为（33.5±4.3）%, 也高于水族缸饲养螺[（9.0±2.3）%, t=10.68， P<0.01]。但随着休眠期的延长其死亡率增高（x²=18.31，P<0.01）。从存活螺体内检获的不同活力的L3幼虫均可感染SD大鼠。 结论 25.0～25.5 ℃ 恒温条件下螺休眠不影响体内幼虫发育，冬季室内自然变温条件下螺休眠或水族缸饲养，其体内幼虫均具有感染性。 感染的福寿螺越冬方式，休眠明显优于水族缸饲养。     

三种方法检测福寿螺肺囊内广州管圆线虫效果的比较研究

目的 比较肺检法、匀浆法和酶消化法检测福寿螺肺囊内广州管圆线虫的效果，以寻找快捷检测方法。 方法 将60只实验室人工感染广州管圆线虫的福寿螺均分2组，分别解剖成螺肺囊与肌肉两部分。镜检两组螺肺囊广州管圆线虫幼虫结节数，用匀浆法和酶消化法分别检测螺肺囊中广州管圆线虫幼虫，比较不同检测方法的效果。酶消化法同时检测福寿螺肌肉内幼虫数，分析螺肺囊与肌肉内幼虫数的相关关系。 结果 肺检法、匀浆法和酶消化法等3种方法检测螺肺囊内幼虫的灵敏度依次为96.7%、93.4%和100%，差异无统计学意义（χ²=2.069，P>0.05）。肺检法的检测速度明显快于匀浆法与酶消化法，差异具有统计学意义（Z=4.782，P＜0.01）；螺肺囊与肌肉组织内的幼虫数呈正相关(r=0.847, P＜0.01）。 结论 肺检法的检测效果与匀浆法和酶消化法相似，但其检测速度更快，适合现场大规模螺体广州管圆线虫的定性筛查。     

结膜吸吮线虫实验室感染大绕眼果蝇

在安徽黄山地区捕捉有绕眼习性的果蝇,将结膜吸吮线虫初产蚴混于果汁中,实验室喂饲感染果蝇,常温饲养20 d后,检查果蝇的感染情况。结果显示,大绕眼果蝇（Amiota magna）和冈田绕眼果蝇（A. okadai）的阳性率分别为30%（30/100）和21.6%（55/255）,两者间的差异无统计学意义（χ²=0.058 4, P>0.05）。将采自大绕眼果蝇的结膜吸吮线虫感染期幼虫接种家兔,35 d后在兔结膜囊内检获结膜吸吮线虫成虫及其初产蚴,表明在实验室条件下,结膜吸吮线虫可感染大绕眼果蝇。     

广东省江门市广州管圆线虫病流行病学调查

目的 对广东省江门市广州管圆线虫病进行流行病学调查。 方法 2006-2007年在广东省江门市礼乐镇和五邑大学及新会市三江镇和双水镇, 调查广州管圆线虫不同宿主感染情况和特征，包括用消化法检测褐云玛瑙螺(Achatina fulica?和福寿螺(Pomacea canaliculata)感染广州管圆线虫(Angiostrongylus cantonensis)Ⅲ期幼虫情况；解剖褐家鼠(Rattus norvegicus)、板齿鼠(Bandicota indica)和黄胸鼠(Rattus flavipectus)心、肺，检查心肺血管中广州管圆线虫成虫感染率；随机抽样问卷调查当地居民广州管圆线虫病史及饮食习惯等。ELISA检测300份居民血清广州管圆线虫特异性IgG和IgM抗体阳性率。 结果 检查褐云玛瑙螺695只，福寿螺720只，其广州管圆线虫Ⅲ期幼虫阳性率分别为45.0%和1.8%；平均感染度分别为53.74±147.30条/只和 5.23±8.51条/只。检查鼠类229只，广州管圆线虫成虫感染率为4.4%。问卷调查300人, 其中11.3%有食生或半生鱼、虾史, 5.3%在劳动中直接或间接接触过褐云玛瑙螺和福寿螺。 检查300份居民血清，IgG抗体阳性42份，阳性率为14.0%，其中IgM抗体阳性5份，阳性率为1.7%。 结论　 江门市为广州管圆线虫病流行区，居民受到该病的威胁。     

异尖线虫Ⅲ期幼虫在不同条件下生存试验及人工感染大鼠观察

目的了解异尖线虫Ⅲ期幼虫(L₃)生物学特性及致病性。方法观察异尖线虫L₃在不同的溶液、温度下的生存时间及感染大鼠后引起的病理变化。结果L3在-20 ℃10 h后被杀死，在4～10 ℃能生存8个月以上。37 ℃时幼虫非常活跃，40 ℃以上可在短时间内死亡。腌制鱼生的配料不能杀死虫体。异尖线虫L3感染大鼠试验证实：约15%～25%的L₃2 d 内可能钻入消化道壁或腹腔，3 d后不再构成危险，7～10 d自行死亡,不能发育为成虫。动物空腹时易感染。病理学研究显示,初次感染以异物反应为特征，再次感染以过敏反应为特征。结论 异尖线虫L₃对外界环境有较强抵抗力，感染陆地哺乳动物后能在体内移行，但不能继续发育。     

宠物仓鼠胃肠道寄生虫感染情况调查

用饱和蔗糖溶液漂浮法、改良抗酸染色法和卢戈碘液染色法对郑州某宠物市场金色仓鼠（Mesocricetus auratus）、黑线毛足鼠（Phodopus sungorus）、坎氏毛足鼠（P. campbelli）和小毛足鼠（P. roborovskii）共153份粪便样品进行检查, 寄生虫感染阳性率分别为70.7%（41/58）、96.7%（59/61）、83.9%（26/31）和100%（3/3）, 平均阳性率为84.3%。共检出8种寄生虫, 分别为隐孢子虫（15.0％）、贾第虫（22.2％）、球虫（2.0%）、短膜壳绦虫（31.4％）、长膜壳绦虫（25.5%）、管状线虫（41.8％）、四翼无刺线虫（7.2%）和毛尾目未定种类（18.3%）。表明宠物仓鼠可感染和传播多种人兽共同感染的寄生虫。     

三种淡水螺与广州管圆线虫相容性的实验研究

目的 比较福寿螺、中国圆田螺、铜锈环棱螺等3种食用淡水螺与广州管圆线虫的相容性。 方法 在相同条件下，用广州管圆线虫福建株感染3种螺，1、3、6、12及24 h后，随机抽样各20只，分别饲养于置有滤水器、水温（24±1）℃ 的玻璃缸内。记录感染2周内各组螺死亡数。第15天开始解剖，记录螺软体重量和感染虫数。同时设不感染螺对照组。 结果 3种螺感染后第1周死亡数达高峰。感染率和死亡率与螺的种类及感染时间均无相关性。虫负荷与虫密度，福寿螺感染6、12及24 h均显著高于感染1 h的（P值均<0.05）；铜锈环棱螺，感染24 h的均显著高于感染 1、3、6及12 h的（P值均<0.05）；中国圆田螺，感染1、3、6、12及24 h各组间差异均无显著性（P值均>0.05）。福寿螺感染6、12及24 h的虫负荷均显著高于铜锈环棱螺和中国圆田螺（P值均<0.05）。 感染6、12及24 h，福寿螺及铜锈环棱螺虫密度均高于中国圆田螺（P值均<0.05）。 结论 3种螺对广州管圆线虫均易感并有较高的相容性， 其中福寿螺的相容性较强。     

南海,渤海鱼类简单异尖线虫幼虫感染的调查

目的：为了解我国南海、渤海各种鱼类中人体异尖线虫病的主要致病原——简单异尖线虫幼虫的感染状况而进行本调查。方法：取南海８８个鱼种３８９尾、渤海２０个鱼种４７１尾，分别测定体长及体重后解剖鱼体进行检查。检获的虫体清洁后用７０％酒精固定，用甘油酒精透明，在显微镜下鉴定。结果：南海部分检获幼虫的鱼种占被检鱼种数的６０．２％（５３／８８），阳性鱼种检得幼虫者占阳性鱼种的５３．６％（１４２／２６５），占所检鱼总尾数的３６．５％（１４２／３８９）；渤海部分检出幼虫的１１个鱼种占所检鱼种的５５％（１１／２０），阳性鱼种总检鱼数３７８尾中，检得幼虫者占阳性鱼种５０．５％（１９１／３７８），占所检鱼总尾数的４０．５％（１９１／４７１）。结论：两个海域中鱼类简单异尖线虫幼虫的感染率都相当高，因此凡生食本文所列的阳性海鱼时，不应疏忽对异尖线虫病的预防。以上在流行病学和食品卫生方面均有重要意义。     

宁波市并殖吸虫病流行现状

收集2000－2007年宁波市疾控中心寄生虫病门诊并殖吸虫病病例资料，调查并殖吸虫病历史流行区人群自然感染情况，以及并殖吸虫第一、第二中间宿主和保虫宿主的感染情况。从2 643份疑似患者血清中检出并殖吸虫抗体阳性417份，阳性率为15.8%，男女比例为1︰1.19，多数病例存在外周血嗜酸粒细胞增高。历史流行区人群血清阳性率为3.1%（46/1 462），男性和女性的感染率分别为2.8%（18/649）和3.2%（26/813），两者差异无统计学意义（x₂=0.183 3，P>0.05）。第一中间宿主川卷螺阳性率为0.05%（9/19 368），第二中间宿主长江华溪蟹和浙江华溪蟹阳性率为31.1%（15 627/50 313），保虫宿主阳性率为11.9%（52/438）。宁波市部分地区仍存在并殖吸虫病的自然疫源地。     

福建省闽东渔场海鱼异尖线虫感染调查

目的 了解福建省闽东渔场海洋鱼类异尖线虫感染情况,为制定异尖线虫病控制策略、保障食品安全提供依据。方法 2021年9—12月在福建省闽东渔场沿海蕉城区、福鼎市、霞浦县随机收集海鱼样本,解剖获取鱼腹腔内容物,在体视显微镜下挑取寄生虫,并在镜下根据异尖线虫形态特征鉴定虫种,计算异尖线虫感染率和感染度。结果 共解剖海鱼24种177尾,其中16种73尾海鱼检出异尖线虫,鱼种检出率为66.7%、海鱼总感染率为41.2%;感染度为1～148条/尾,平均感染度为14.3条/尾。异尖线虫感染率较高的鱼种为鳓鱼(5/5)、鮸鱼(3/3)、包公鱼(2/2)、马鲛鱼(12/13)、带鱼(19/23)、白姑鱼(6/11)、海鲫鱼(14/27),平均感染度依次为9.2、2.7、4.5、10.9、39.2、4.5、2.1条/尾。检出的异尖线虫幼虫经鉴定为异尖线虫属和宫脂线虫属。结论 福建省闽东渔场海洋鱼类异尖线虫感染率较高,应加强饮食健康宣传,防止人群异尖线虫病发生。     

Rates of infection of fishes from Okhotsk sea with human Anisakidae]

In 1987 to 1999, large-scale studies were conducted in the Okhotsk Sea basin for marketable fish infection with Anisakidae larvae that are a hazard to human health. A total of 9223 fishes of 18 species and 455 fishes of 5 species were examined in the North and South-West Okhotsk Sea Regions, respectively. In the North Okhotsk Sea Region, the larvae were detected in 58.8 (0.5% specimens of all species with the highest rates in the rasp (100%), Siberian salmon 93.9 (0.8%), herring 91.2 (0.7%), silver 90.9 (1.6%), halibut 89.7 (3.1%), Greenland halibut 87.3 (4.2). In the South-West Okhotsk Sea Region, the total fish infection rates were 69.8 (2.6%) and those of the commonly caught species Siberian salmon and humpback were 82.8 (3.3 and 67.9 (3.6%), respectively. The infection rates varied both at the inter- and intraspecies-specific levels, as well in areas and fishing seasons. Fresh fish processing (freezing and salting) causes no Anisakidae larval migration in the flesh.     

A comparative study on the parasite fauna of perch, Perca fluviatilis L., collected from a freshwater coastal lake, brackish-water Baltic Sea, and the interconnecting canal

BACKGROUND: Parasitological surveys of freshwater fishes rarely include comparisons between two ecologically different bodies of water. Such studies might help to understand processes of establishment of parasite faunas in estuary areas. The results obtained could also provide useful tools for discriminating various fish populations based on the composition of their parasite faunas. The present authors attempted to study such data from Resko Lake-a freshwater coastal lagoon (6 km2 surface area), and the adjacent areas of the Baltic Sea. Resko Lake, located 12 km west of the city of Ko?obrzeg, is shallow (1.5 m) and is connected to the sea through a small canal (1.3 km long, 30 m wide). MATERIAL AND METHODS: The material was collected from April 1969 and July 1970. A total of 159 perch were collected, in this number 104 fish from the lake, 43 from the sea, and 12 from the canal. RESULTS: A total of 32 parasite species were recovered from the fish necropsied. The parasites represented 7 higher taxa: Protozoa (3 species), Cestoda (4), Digenea (13), Nematoda (5), Acanthocephala (3), Mollusca (1), and Crustacea (3). The parasite fauna of perch from the sea was definitely more abundant (31 species) compared to that of the lake (21), and the canal (12 species). Infection parameters of 13 parasite species demonstrated significant differences between the locations studied. The infection level of 6 parasite species was significantly higher in perch from the sea: Bothriocephalus scorpii, Ligula sp., Brachyphallus crenatus, Camallanus truncatus, Hysterothylacium aduncum, and Echinorhynchus gadi. On the other hand, infection levels of 7 other species were higher at the lake: Triaenophorus nodulosus, Bucephalus polymorphus, Azygia lucii, Tylodelphys clavata, Camallanus lacustris, Acanthocephalus lucii, and Achtheres percarum. The infection parameters of the fish from canal were similar to those from the lake. Interesting observations were made on the seasonality of certain parasites of both lake- and Baltic perch. The presently observed differences between parasite faunas of the fish from ecologically different adjacent estuarine locations are certainly caused by diversified environmental conditions that affected the processes of formation of the parasite communities there. Among important factors that could affect compositions of the parasite faunas could have been: availability of the intermediate hosts, exchange of waters (Baltic water influxes to the lake), fish migrations (spawning), and finally the separate identity of the two fish stocks studied.     

Long-Term Changes in Fish Assemblage Structure in the Yellow River Estuary Ecosystem,China

Abstract

The Yellow River estuary ecosystem is an important spawning ground for many species found in the Bohai Sea and Yellow Sea and contributes substantially to the fishery resource structure and biological reproduction in the northern China Sea. Based on long-term ecosystem surveys in the Yellow River estuary during the main spawning period (May) of most fishery species from 1959 to 2011, the responses of the ecosystem, including regime shifts in species composition, biomass, diversity, and other related factors, were analyzed in this study. Since the 1980s, the dominant large-size species of high economic value (e.g., Largehead Hairtail Trichiurus lepturus) have been replaced by short-lived, low-trophic-level, planktivorous pelagic species (e.g., Scaly Hairfin Anchovy Setipinna taty and Japanese Anchovy Engraulis japonicus). Currently, traditional commercially targeted fishes, such as the Largehead Hairtail, Red Seabream Pagrus major, and Pacific Herring Clupea pallasii, are locally extinct. There has been a rapid shift of dominant species from highly valued, high-trophic-level, large-sized demersal species with complicated age structures to low-value, low-trophic-level, small-sized pelagic species with simple age structures; this shift has resulted in major changes to the ecological cycle and restoration of fishery resources. The fish catch declined from 421.66 kg/h in 1959 to 0.25 kg/h in 2008 and then increased to 3.62 kg/h in 2011. Diversity and evenness indices showed a continuously increasing trend during 1959–2011. The Yellow River estuary may be significantly compromised by overfishing, climate change, dam construction, and pollution, resulting in the decline of traditional fishing industries and reduced biodiversity in this ecosystem.

Received August 30, 2012; accepted January 11, 2013     

广西淡水鱼携带异形科吸虫囊蚴的调查研究

目的了解广西淡水鱼异形科吸虫感染情况。方法使用消化法对从桂北的阳朔县及桂南的南宁市、马山县、扶绥县和宾阳县等地采集的淡水鱼进行检查。结果共检查各种鱼类316尾,分属鲤科33种、Centropomidae科和丽鱼科各1种。鲤科鱼33种中有28种、Centropomidae科的Coreoperca whiteheadi 1种带有异形吸虫囊蚴。共检出后殖吸虫、扇棘单睾吸虫、钩棘单睾吸虫和台湾棘带吸虫等4种异形吸虫囊蚴,其感染率分别为28.2%、27.5%、44.3%和10.8%。桂北检查112尾,后殖吸虫感染率为78.6%;桂南检查204尾,钩棘单睾吸虫感染率最高,为63.2%,其次为扇棘单睾吸虫42.7%和台湾棘带吸虫16.7%,后殖吸虫为0.5%。结论广西各地淡水鱼异形吸虫感染非常普遍和严重,尤以桂南为甚。异形吸虫与华支睾吸虫感染方式相同、流行区域重叠及虫卵形态相似,临床上要注意其鉴别诊断。     

Helminths of Antarctic fishes

Antarctic fishes are represented by sharks, skates (Chondrichthyes) and bony fishes (Teleostei). Teleosts play an important role in the completion of life cycles of many helminth species. They serve as either definitive or intermediate and paratenic hosts. Chondrichthyes are definitive hosts only. Seventy three helminth species occur as the adult stage in fishes: Digenea (45), Cestoda (14), Nematoda (6), Acanthocephala (8), Also, 11 larval stages of Cestoda (7) and Nematoda (4) are known, together with 7 species of Acanthocephala in the cystacanth stage. One digenean species, Otodistomum cestoides, matures in skates. Among cestodes maturing in fishes only one, Parabothriocephalus johnstoni, occurs in a bony fish, Macrourus whitsoni. Antarctic Chondrichthyes are not infected with nematodes and acanthocephalans. Cestode larvae from teleosts belong to Tetraphyllidea (parasites of skates), and Tetrabothriidae and Diphyllobothriidae (parasites of birds and mammals). Larval nematodes represent Anisakidae, parasites of fishes, birds and mammals. Acanthocephalan cystacanths mature in pinnipeds and birds. The majority of parasites maturing in Antarctic fishes are endemics. Only 4 digenean and one nematode species, Hysterothylacium aduncum, are cosmopolitan. All acanthocephalans, almost all digeneans, the majority of cestodes and some nematodes occur mainly or exclusively in benthic fishes. Specificity of the majority of helminths utilizing teleosts as intermediate and/or paratenic hosts is low. Among parasites using fishes as definitive hosts, all Cestoda, most Digenea and Nematoda, and almost all Acanthocephala have a range of hosts restricted to one order or even to 1-2 host species.     

Population Dynamics of Fish Species in a Marine Ecosystem: A Case Study in the Bohai Sea,China

There were rapid shifts of the dominant species in the Bohai Sea from the 1950s to the 1990s, with large-sized, high-valued species (e.g., Small Yellow Croaker Larimichthys polyactis and Largehead Hairtail Trichiurus lepturus) being replaced by small-sized, low-valued species (e.g., Japanese Anchovy Engraulis japonicus and Hairfin Anchovy Setipinna taty). From the 1990s to the present, the Small Yellow Croaker and some of the small-sized species (Hairfin Anchovy and Dotted Gizzard Shad Konosirus punctatus) have become the dominant species. The food web is now simple, with species from relatively low trophic levels controlling the energy flow within the fishery ecosystem. Along with the shift in community structure, the abundance of dominant species changed, the diversity of fish species and species number density decreased, and interannual and seasonal variations in species number density were found. Fish abundance had a decreasing trend and fish interannual and seasonal distribution greatly changed. Variation in the sizes of the ecological niches of the dominant species regulated the succession of the fish community, and the alteration of ecological niches caused changes in the fishery community.

Received August 11, 2014; accepted September 30, 2015     

Colonization of the round goby, Neogobius melanostomus (Gobiidae) by parasites in the new environment of the Gulf of Gdańsk (Southern Baltic)

The round goby (Neogobius melanostomus) is a non-indigenous species in the Baltic Sea, introduced to its waters (the Gulf of Gdańsk) from the Black, Azov, and Caspian Seas. For this reason, an attempt was made to determine the species' parasitic fauna in its new environment. Within 1994-2000, a total of 201 round goby specimens caught in the Gulf of Gdańsk were examined. The parasites found represented protozoans (Trichodina domerguei domerguei), digeneans (Diplostomum spp. metacercariae), cestodes (Bothriocephalus scorpii, plerocercoids), nematodes (Hysterothylacium aduncum L3, L4, and adults), and acanthocephalans (Echinorhynchus gadi and Pomphorhynchus laevis). The parasitic species found are common in the Gulf of Gdańsk. It should be emphasized that, since the round goby has only recently appeared in the Gulf, the parasitic fauna of this fish is not yet complete.     

广西柳江河鱼类华支睾吸虫囊蚴感染情况

2008年3月～2009年3月,在广西柳江河段上的三江县、融安县、融水县、柳城县、柳州市和象州县设点,采集各地河道内的鱼类,用直接压片法和消化法检查其感染华支睾吸虫的情况。共捕获鱼16204尾,经鉴定分属9科27属35种,其中32种不同程度感染华支睾吸虫,感染率为10.5%,感染度为4.6个/g。麦穗鱼(Pseudoras bora parva)的感染率(21.5%)和感染度(9.9个/g)最高,其次为宽鳍鱲(Zacco platypus),感染率为17.8%,感染度为8.9个/g。各河段感染率间的差异有统计学意义,象州县河段感染率(12.3%)较高,三江县河段(9.1%)和柳州市区河段(9.7%)感染率较低。统计学分析表明,夏、秋两季鱼的感染率较高,春、冬两季较低;中、上水层鱼类的感染率较高,下水层鱼类较低;杂食性和草食性鱼类的感染率较高,肉食性鱼类较低。