Some Copepod and Isopod Parasites of Bermuda Marine Fishes

Abstract

Three species are added to the depauperate parasite fauna of Bermuda: Caligus balistae, Lernanthropus talipes, and Alcirona insularis. The latter, normally a rare associate, seems to thrive on groupers (Serranidae) in captivity. An offshore record for Nerocila lanceolata on ocean triggerfish Canthidermis sufflamen contrasts with its known nearshore occurrence. A new host record is noted for each of four parasites occurring in Bermuda: Caligus balistae, A. insularis, Cymothoa oestrum, and N. lanceolata     

Lingering Effects of the 1987 Mass Bleaching of Puerto Rican Coral Reefs in Mid to Late 1988

Abstract

Puerto Rican coral reefs were surveyed with photo-transects and remotely operated vehicle observations, and permanently tagged individual corals were monitored. Seven of eight photo-transects examined between April and October 1988 had bleached or pale colonies of eight species of corals. Between 2.7 and 19% of the living coral surface area was affected on a transect. These observations indicate that additional bleaching occurred after the recovery of most photosymbiotic hosts in January 1988. This continued bleaching may represent the longest bleaching event ever recorded. Individual coral colonies that were bleached in October 1987 were permanently tagged and photo-documented in the field. Recovery of some of these colonies took more than 5 months. Some previously living parts of these colonies died and were overgrown by algae by January 1988. Surveys by remotely operated vehicle during 10–13 February 1988 disclosed bleached colonies of Agaricia spp. toa depth of 60 m and unbleached colonies to a depth of 89 m.     

New Host and Locality Records for Copepod and Isopod Parasites of Colombian Marine Fishes

Abstract

Two copepods and three isopods, representing five families of Crustacea, are noted from ten hosts, eight of these representing new host records. Cardiodectes rubosus (Copepoda: Pennellidae) is reported from the Atlantic Ocean for the first time. Excorallana tricornis (Isopoda: Corallanidae) may be a more important fish parasite than previously thought.     

A Digenean Metacercaria (Apophallus sp.) and a Myxozoan (Myxobolus sp.) Associated with Vertebral Deformities in Cyprinid Fishes from the Willamette River,Oregon

Abstract

A high prevalence of vertebral deformities has been observed in various fishes, especially cyprinids, from certain regions of the Willamette River for many years. One proposed source of these deformities is exposure to toxicants. Histological evaluation of affected chiselmouth Acrocheilus alutaceus revealed that all lesions associated with vertebrae were associated with metacercariae of digenean trematodes. Approximately half of the northern pikeminnow Ptychocheilus oregonensis had infections in which metacercariae were associated with these lesions. Metacercariae were also associated with vertebral lesions in three of four affected peamouth Mylocheilus caurinus. Many metacercariae that were present within the vertebral bodies were associated with bony dysplasia and bony proliferation in all three species. We also evaluated the association of the metacercariae with the vertebral deformities, using intact fish that had been cleared with trypsin. Fish from the affected regions had a much higher prevalence of metacercariae and deformities and a greater abundance of metacercariae than those in the reference site. Chiselmouths had more deformities and metacercariae than northern pikeminnow. In all fish species, 77% of deformities were directly associated with metacercariae; in chiselmouths, about 95% of the deformities exhibited this relationship. Two types of metacercariae were identified in affected fish: Apophallus sp. (Heterophyidae) and a neascus type (Strigeidida). The Apophallus sp. appeared to be more closely associated with the skeleton deformities. A Myxobolus sp. morphologically similar to M. cyprini was also associated with the vertebral lesions in about 50% of the northern pikeminnow and 5% of the chiselmouths. Intact plasmodia were found in somatic muscle, and lesions containing free spores were often located at bone surfaces. This survey demonstrates that metacercariae (probably Apophallus sp.) and a Myxobolus sp. are major causes of the vertebral deformities seen in cyprinid fishes from certain regions of the Willamette River.     

The Marine Commercial Fishes of Our Country Are Nearly on the Brink of Extinct

Zhoushan fishery was once the biggest offshore fishery. for the winter season Trichiurus haumela in China, attracting thousands of fishermen and crowded by hundreds of fishing boats from all over the country every year. In order to fish Trichiurus haumela, the single trawl was innovated into the pair trawl, that is,     

Behavior of Rocinela angustata (Isopoda,Aegidae), an Ectoparasite of Alaskan Marine Fishes

Abstract

Observations were made on the feeding and host selection behavior of the aegid isopod Rocinela angustata. Host susceptibility was assessed by placing isopods into laboratory tanks containing 14 common species of Alaska marine fishes. Five species of Sebastes and Blepsias bilobus were attacked within a few minutes of the introduction. Five species—Enophrys bison, Eumicrotremus orbis, Hexagrammos lagocephalus, Pleuronectes asper, and Pholis laeta—were attacked 10–24 h after introduction of the isopods. Three species—Podothecus acipenserinus, Liparis gibbus, and Lycodes brevipes—were not successfully attacked, even when held in isolation with an isopod for 14 d. Starved isopods isolated with B. bilobus attached to fish within 1 h and remained attached 4–14 d. The isopods reattached 1–4 d after detachment. Isopod digestive tracts cleared within 24 h after detachment.     

观赏鱼与观赏鱼饲料

观赏鱼既有淡水品种,又有海水品种,尤以金鱼、锦鲤、热带鱼为主。饲养观赏鱼在我国有着悠久的历史。我国是金鱼的原产地,自宋朝初年开始驯化和家养,距今已有1200多年。16世纪初传入日本,300年前传入欧洲,100年前传入美国,现已成为世界性品种。     

Some Parasitic Worms in Freshwater Fishes and Fish-Predators from the Transvaal,South Africa

This report concerns a collection of parasitic worms from South Africa, and contains a new species of monogenean, Gyrodactylus transvaalensis, six species of adult trematodes, including a new species of Phyllodistomum.P. van der waali, two metacercariae of the Family Clinostomidae and three of the Order Strigeida, as well as two species of cestodes, and larvae of the nematode genus Contracaecum. The adults of previously-known helminths are redescribed, with some remarks on their systematics and biology. Accompanying the material of the new gyrodactylid monogenean there is a specimen which is thought to be a giant of the new form, and this appears to be the first recorded suggestion of the occurrence of gigantism in the Monogenea, and in fact in any kind of helminth.     

Immunodeficiency Diseases in Marine Mollusks: Measurements of Some Variables

Abstract

Immunity in bivalves comprises cell-mediated and humoral mechanisms. Because bivalves (and gastropods) possess open circulatory systems, studies were conducted to ascertain whether copper and cadmium ions that enter eastern oysters Crassostrea virginica would compromise certain aspects of the animals' cell-mediated and humoral immunity. In vivo exposure to a 1-mg/L concentration of Cu²⁺ was more lethal to eastern oyster hemocytes than exposures to 1-mg/L concentrations of Cu²⁺ plus EDTA, Cd²⁺, or Cd²⁺ plus EDTA. However, in vivo exposures to 1-mg/L concentrations of both metals alone and in the chelated forms had no effect on the chemotactic attraction between hemocytes and sonicated Escherichia coli. Also, measurements of enzyme activities in eastern oysters challenged in vivo with 1-mg/L concentrations of Cu²⁺, Cu²⁺ plus EDTA, Cd²⁺, or Cd²⁺ plus EDTA revealed that Cd²⁺ inhibited the release of lysozyme into serum, Cu²⁺ inhibited the release of acid phosphatase into serum, and Cu²⁺ stimulated the intracellular synthesis of β-glucuronidase in hemocytes but inhibited the release of this enzyme into serum. In view of the above and previously published information, it is now known that in vivo exposure to certain heavy metals, as well as alterations in salinity and temperature, will compromise the internal defense mechanisms of mollusks.     

危情救赎当长江沦为“没有生命的死水”

我们赞美长江,你是无穷的源泉……长久以来,长江哺育和支撑着一代代的中华儿女,这支气势磅礴的《长江之歌》也留存在了人们的记忆之中.可如今,这位曾经无私奉献的母亲似乎已然年老色衰,风光不再了.作为长江多年的原住民,多种鱼类正在前赴后继地与死神会面,曾拥有的其他河流难以匹敌的渔业资源已经被永远地尘封进了泛黄的历史.目前,长江全流域每年鱼类的天然捕捞量已经减少到年10万吨左右,资源量已不足以支撑长江流域14多万渔民的基本生活——这个数字绝望到令人癫狂.     

中国西南区畜禽吸虫名录(四)

本文收录我国西南区(四川、重庆、云南、贵州和西藏)寄生于鸡、鸭、鹅、兔、猪、山羊、绵羊、黄牛、水牛、牦牛、奶牛、马、驴、骡、犬、猫的吸虫，共发现170种，隶属于19科，52属。     

二等公民波多黎各《少年派》中的奇幻荧光海

2012年11月,波多黎各频频曝光于世界各大媒体,原因是:尽管这里属于美国的自由邦,所有人都是美国公民,但对美国总统大选他们只能干瞪眼——没有总统选举权.这样的待遇自然引起了当地人的不满,所以,在关于波多黎各未来去向举行的全民公投中,大多数人的选择是:让波多黎各成为美国的第51个州.     

Recreational Angler Perspectives of Nonnative Fishes

Although fish invasions have implications for conservation and resource management, research on public attitudes toward nonnative fishes is lacking. We surveyed boat and canal bank recreational anglers in the Everglades to assess their awareness, preferences, and perspectives of native versus nonnative fishes. Our findings showed that 79% of anglers were aware of the presence of nonnative fishes, and overall awareness was positively affected by the frequency of fishing, and years of angler experience at study sites. Frequency of fishing had a stronger effect on canal bank anglers. Boat anglers had higher awareness of nonnatives, higher familiarity with “nonnative” terminology, and expressed greater preferences for native fish. Most anglers favored native species (72% preference), and targeted native fishes, particularly Florida Largemouth Bass (66%). Overall, findings show that despite the prevalence of nonnative species, anglers favored native fishes and supported native fish conservation.     

Genetics of Melanomas in Xiphophorus Fishes

Abstract

Data are presented from studies on heritable melanoma formation in certain hybrids of Xiphophorus fishes. In the best investigated case, benign and malignant melanomas were caused primarily by hemizygous and homozygous loss, respectively, of a tumor suppressor gene that promoted final pigment cell differentiation, although additional genetic events may be of importance. In other melanoma cases, different genes, most of them presumably also tumor suppressor genes, have been implicated in the development of melanomas and may interact at other levels of pigment cell development, such as commitment, migration, or homing of pigment cell precursors. Importantly, genetic factors have been identified that do not allow melanoma formation despite the loss of tumor suppressor genes. Taken together, these findings stress the complexity of tumorigenesis and the heterogeneity of pathways that lead to cancers of the same histological type.     

中国淡水鱼类种质资源的保护和利用

本文简要介绍了目前世界鱼类资源概况、我国鱼类资源现状，以及鱼类生物多样性的极丰富程度与易被破坏性，还介绍了造成鱼类种类减少或区系组成变化的主要原因以及造成鱼类遗传多样性减少的内在原因和外部原因；比较详细的提出了鱼类种质资源保护的目的、策略及措施。并就我国鲤科鱼类繁育群体的大小、鱼类种质的鉴定与评价及利用前景作了分析。     

鳖鱼混养技术

鳖鱼混养是指精养中华鳖池塘中套养服务性鱼类的养殖模式,是实行中华鳖健康养殖的重要措施,它的优点和好处是：①可以充分利用水体,增加池塘的单位放养量,从而提高鳖鱼产量,降低成本,增加效益。鳖是水陆两栖爬得动物,靠肺呼吸,不存在与鱼争氧,增加水体负债。②发挥鱼鳖之间的互利关系,增加池水溶解氧,优化水体生活环境。鳖在水中不断活动,经常浮出水面进行呼吸,这样来回往返活动,可使表层水与底层水得到交换,防止浮游植物旺盛的光合作用产生的过饱和氧逸出,又可弥补深层水的“氧债”,且有利于淤肥中营养盐的释放,有利浮游…     

中国淡水鱼类种质资源的保护和利用

本文简要介绍了目前世界鱼类资源概况、我国鱼类资源现状,以及鱼类生物多样性的极丰富程度与易被破坏性,还介绍了造成鱼类种类减少或区系组成变化的主要原因以及造成鱼类遗传多样性减少的内在原因和外部原因;比较详细的提出了鱼类种质资源保护的目的、策略及措施.并就我国鲤科鱼类繁育群体的大小、鱼类种质的鉴定与评价及利用前景作了分析.