Monogenetic Trematodes Research Articles

Clinical and Pathological Investigation of <i>Nandus nandus</i> Collected from Fish Markets of Mymensingh

An experiment was carried out in order to investigate the health status of Nandus nandus based on clinical and histopathological observation collected from three fish markets of Mymensingh district. The study was conducted for a period of six months from October 2005 to March 2006. Clinically, it was evident that fishes were more affected having scale loss and deep dermal ulceration in the months of December and January, which were observed in Sankipara Railway Crossing and Gollpukurpar markets. But fish appeared almost normal during October to November and February to March collected from the three fish markets. Histopathologically, marked necrosis, pyknosis, haemorrhage, vacuoles and fungal granuloma were observed in skin, muscle and kidney. Gills had monogenetic trematode, hypertrophy and melanomacrophages in December and January. Liver of examined fishes had less pathological signs compared to other organs. However, Nandus nandus was found more affected in Gollpukurpar and Sankipara Railway Crossing markets compared to K-R market. From overall observation, it could be concluded that fishes were severely affected by EUS and dactylogyrosis during the months of December and January.DOI: http://dx.doi.org/10.3329/pa.v18i2.18193 Progress. Agric. 18(2): 167 - 174, 2007

Parasites of commercially important fish from Lake Naivasha, Rift Valley, Kenya

In Lake Naivasha, the common carp Cyprinus carpio L. 1758 was accidentally introduced from fish farms adjacent to River Malewa in 1999 and now forms the bulk of the total fish caught. Since its introduction, no study has been made on its parasitic community nor are there any reports on ectoparasites from other fish species in this lake to the best of our knowledge. Therefore, the aim of this study was to describe the parasitic community of C. carpio and two other commercially important fish species: Oreochromis leucostictus and Tilapia zillii. Additionally, the abundant Barbus paludinosus was included in the study. A total of 286 fish (145C. carpio, 56 O. leucostictus, 18 T. zillii, and 67 B. paludinosus) were collected during the year 2011 and examined. Ten taxa of parasites were recovered from C. carpio dominated by the monogenean Dactylogyrus minutus, occurring with a prevalence (p) of 99.3%. Thirteen taxa of parasites were identified from O. leucostictus dominated by monogeneans Cichlidogyrus spp. (p = 91.1%). T. zillii harbored nine taxa of parasites with the digenean Tylodelphys sp. (p = 83.3%) being dominant and B. paludinosus harbored 11 taxa of parasites dominated by an unidentified monogenean of the genus Dactylogyrus (p = 83.6%). C. carpio had the lowest helminth species diversity and richness while monogenetic trematodes, which have never been reported from fish in Lake Naivasha, were the most prevalent parasites recovered.

Molecular Investigation on Clinopathological, Genetic and Biochemical Changes in Channa punctata Infected with Internal Parasites and Subjected to Metal Pollution in Chittagong, Bangladesh

This study was carried out to investigate the effects of parasites and metals in the fishes of fresh water sources of three different stations of Hathazari Upazilla, Chittagong, Bangladesh, by analyzing blood biochemical parameters and body composition of Channa punctata. The results indicated that, the highest rate of parasitic infection change the blood parameters spontaneously. Findings of blood biochemical factors (blood sugar, hemoglobin and creatinine) revealed significant variation between infected and uninfected fishes. Considerable works mainly on systematics, nature of infestation and pathology of different groups of fish parasites - Cystode, Trematodes and Nematodes have been done. Different species of parasites as endoparasitic Cystode and monogenetic Trematodes were recorded mainly from fish species of different water sources. One helminth parasite Nematode also reported from those fishes. Much attention has been given on observing intestine, liver and kidney. Molecular observation including DNA extraction has been done from both infected and healthy fish blood samples. Purification of DNA has been confirmed by Nano drop. Recommendation has been made for the future works on parasitology for sustainable production of healthy fishes by heavy metal detection, molecular observation as well as mutation detection.

Clinical and Histopathological Study of Important Air-Breathing Fishes

A study was conducted to know the health and disease problems of three important air-breathing fishes viz. Shing (Heteropneustes fossilis), Magur (Clarias batrachus) and Thai Koi (Anabas testudineus) through clinical and histopathological technique from June 2007 to March 2008 collected from selected farms and from local markets. Generally, during December and January, acute pathologies were recorded. Clinical signs of Shing included haemorrhage, extended belly and ulceration. Histopathologically, partly missing and splitted epidermis and dermis, necrotic, vacuoled and ruptured myotomes of muscle with fungal granuloma were observed. Major gill pathologies included partly missing and highly hypertrophied, haemorrhagic gill lamellae, presence of monogenetic trematode and pyknotic cells. In liver, haemorrhagic areas, necrotic, vacuoled, hyperplasid hepatocytes, cell debris, pyknotic nuclei and plenty of inflammatory cells were evident. Haemorrhages, vacuolation, necrosis, missing and ruptured kidney tubules and pyknotic nuclei were the major pathologies of kidney. Clinically, dark red lesion, haemorrhage, necrosis and ulcer in body surface were seen in Magur. Histopathologically observed pathologies in Magur were almost similar to that of Shing. Clinical signs of Thai Koi included discoloration, loss of scales and fins, abnormal caudal fin, haemorrhage in gill and ulcer. Marked histopathology in the skin and muscle were observed such as totally lost epidermis, dermis separated from muscle, severely ruptured, degenerated and missing of myotomes in many places. In gills, hypertrophy, hyperplasia, telangiectasis, clubbing, haemorrhage and massive necrosis in both primary and secondary gill lamellae were found. Pathologies observed in liver and kidney were most alike to that of Shing. In the months of February and March, all the investigated organs of the three fish species were at a healing stage.DOI: http://dx.doi.org/10.3329/pa.v19i1.17109 Progress. Agric. 19(1): 69 - 78, 2008

Efficacy of Bath Treatments of Formalin and Copper Sulfate on Cultured White Bass, Morone chrysops, Concurrently Infected by Onchocleidus mimus and Ichthyophthirius multifiliis

Concurrent ectoparasite infections on fishes are commonly encountered in the wild and in aquaculture (Rohde 1984; Hoffman 1999), for example, infections of both Ichthyophthirius multifiliis Fouquet, 1876 (Hymenostomatida: Ichthyopththiriidae; Colorni 2008) and gill‐infecting monogenoids (Platyhelminthes: Monogenoidea; Whittington and Chisholm 2008). The decision to aggressively treat infections of either of these parasites can be prudent in aquaculture systems. Both taxa have direct life cycles and short generation times, which may result in high infection intensities that can debilitate or kill the fish host (Noga 2010). Various chemical therapies have been evaluated to prevent, reduce, or eliminate such infections. Typical treatments for killing monogenoids include: freshwater or saltwater baths, formalin, copper sulfate (CuSO4), hydrogen peroxide, mebendazole, trichlorphon, and praziquantel (Whittington and Chisholm 2008). Treatments for infections of I. multifiliis (Ich) include: temporary exposure to high temperature, formalin, malachite green, CuSO4, potassium permanganate, and sodium chloride (Colorni 2008). Despite the common occurrence of these parasites on fish, little species‐specific information exists for the vast majority of fish–parasite combinations across the diversity of culture systems and captive settings. Formalin is approved by the US Food and Drug Administration (US FDA) for use as a treatment for external monogenetic trematodes in fish at up to 250 mg/L for up to 1 h (US FWS/AFS 2008). The ambiguity of this recommendation suggests a wide therapeutic range with no interpretation of repeated applications. Likewise, little information exists on the safety or efficacy of repeated formalin treatments on fish, and CuSO4 has an indeterminate approval status but is widely accepted as having high efficacy. In October 2009, white bass, Morone chrysops (Rafinesque, 1820; Perciformes: Moronidae), in a flow‐through culture system were diagnosed with concurrent infections of the gill‐infecting monogenoid Onchocleidus mimus (Mueller, 1936; Monogenoidea: Ancyrocephalidae) and Ich. O. mimus has a direct life cycle with no intermediate host required and as the intensity of infection increases can become problematic to a population. This study reports an opportunistic evaluation of the efficacy of repeated applications of formalin and CuSO4 to reduce, control, or eradicate these infections in cultured white bass.

Redescription of Neopolystoma liewi Du Preez and Lim, 2000 (Monogenea: Polystomatidae), from Cuora amboinensis (Testudines: Geomydidae) with Notes on Specimen Preparation

Abstract Neopolystoma liewi Du Preez and Lim, 2000, is redescribed on the basis of specimens collected from the type host, Cuora amboinensis, in Malaysia during 2008. Morphometric comparison of the new specimens with the original description revealed significant differences because of differences in specimen preparation. The current material was killed in hot formalin without coverglass pressure, whereas the specimens from the original description were killed and fixed with coverglass pressure. Coverglass pressure resulted in increases of 30%–70% in most measurements of body organs. Sclerotized structures (genital and haptoral hooks and eggs) or structures with sclerotized supports (haptoral suckers) were not affected by coverglass pressure. The coefficient of variation of measurements from worms killed with hot formalin was low (<10%) for most structures. The authors recommend discontinuing the use of flattening in the preparation of monogenetic trematodes, with the exception of a small number of specime...

Single and combined genotoxic and cytotoxic effects of two xenobiotics widely used in intensive aquaculture

Several chemicals are used in aquaculture to prevent or to treat disease outbreaks. These substances are mainly administered by two different routes: by prolonged immersion or by mixing into the diet. In the case of intensive aquaculture, the chemicals that are most frequently applied by immersion are formaldehyde (FA) 37% and oxytetracycline (OTC). The first is highly effective against most protozoa, as well as some of the most common parasites such as monogenetic trematodes. OTC presents a large spectrum of antibacterial activities and is used to treat systemic bacterial infections that affect fish. Under therapeutic use, FA (37%) is applied prophylactically at 200ml/m3, whereas OTC is used curatively at 40g/m3. The goal of the present study is to assess genotoxic and cytotoxic effects associated with exposure of the European sea bass (Dicentrarchus labrax) to FA37% and OTC under the same conditions as those applied in intensive aquaculture systems. To this end the micronucleus (MN) assay was applied in erythrocytes. Our results show that both tested chemicals present genotoxic and cytotoxic potential following a time-dependent pattern. Remarkably, the combined treatment induces a cumulative effect, which is particularly pronounced after 15 days of exposure. This suggests the critical hazards associated with exposure to FA and OTC when applied or released together.

Parasitic fauna of spiny eel Mastacembelus mastacembelus from Greater Zab river in Iraq

A total of 128 spiny eels Mastacembelus mastacembelus (Mastacembelidae) were collected from the Greater Zab river at Iski Kalak town, west of Erbil city, Kurdistan region, Iraq, from July 2007 to the end of June 2008. The fish were examined for ecto and endo parasites. The study revealed the existence of 16 species of parasites (with a total prevalence of 89.06%) including: two species of protozoans (Trypanosoma sp. and Trichodina pediculus), one species of monogenetic trematodes (Mastacembelocleidus heteranchorus), six species of digenetic trematodes (Allocreadium transversale, Asymphylodora macracetabulum, Pseudochetosoma salmonicola, Clinostomum complanatum, Diplostomum flexicaudum and D. spathaceum), two species of cestodes (Polyonchobothrium magnum and Ligula intestinalis), two species of nematodes (Agamospirura sp. and Procamallanus viviparus), one species of leech, crustacean and arachnoide (Cystobranchus mammillatus, Argulus foliaceus and Arrenurus sp. respectively). Five species of these parasites (T. pediculus, A. transversale, D. flexicaudum, C. mammillatus and Arrenurus sp.) were recorded for the first time in Iraq. In addition, M. mastacembelus was regarded as a new host for A. macracetabulum, C. complanatum and A. foliaceus.

Study on the Parasitic Fauna of Carps in Al-Furat Fish Farm, Iraq Treatment of the Common Carp (Cyprinus carpio) Infected with Monogenetic Trematodes by Using Some Plant Extracts

A series of experiments were conducted for the first time in Iraq to evaluate the efficacy of five plant leaves extracts (Ibicella lutea, Nerium oleander, Clerodendron inerme, Allium cepa and Eucalyptus spp.) in treating the common carp (Cyprinus carpio) infected with monogenetic trematodes of genera Dactylogyru and Gyrodactylus. Five different concentrations of such extracts were used to bath fishes for 5, 10, 15, 20 and 25 minutes. A concentration of 15% onion leaves, A. cepa for 25 minutes of bath exposure was effective in trematode eradication. Extracts of both Eucalyptus and N. oleander at a concentration of 10 % each were also effective for ten minutes exposure. Extracts of false yasmine leaves, C. inerme had no any effect on such parasites. On the other hand, extracts of I. lutea caused a serious damage to treated fishes when used at different concentrations and at different periods of exposure.

Treatment of the Common Carp (Cyprinus carpio) Infected with Monogenetic Treatodes by Using some Plant Extracts

A series of experiments were conducted for the first time in Iraq to evaluate the efficiency of five plant leaves extracts (Ibicella lutea, Nerium oleander, Clerodendron inerme, Allium cepa and Eucalyptus spp.) in treating the common carp (Cyprinus carpio) infected with monogenetic trematodes of genera Dactylogyrus. Five different concentrations of such extracts were used to bathe fishes for 5,10,15,20 and 25 minutes. A concentration of 15% A. cepa for 25 minutes of bath exposure was affective in trematode eradication. Extracts of both Eucalyptus and N. oleander at a concentration of 10% each were also affective for ten minutes exposure. Extracts of C. inerme had no any effect on such parasites. On the otherhand, extracts of 1. hitea caused a serious damage to treated fishes when used at different concentrations ans at different periods od exposure.

Population ecology and infestation of monogenetic trematodes in juvenile carp fishes of Mymensingh

Population ecology and infestation of monogenetic trematodes in juvenile carp fishes of Mymensingh

SENSITIVITY OF THE MONOGENETIC TREMATODE DACTYLOGYRUSLAMELLATUS AND THE HOST GRASS CARP CTENOPHARYNGODONIDELLA TO DIFFERENT CONCENTRATIONS OF EARTHTEC™

T _ Tfcjff he effectiveness of EarthTec compound against the monogenetic trematode Dactylogyrus lamellatus was assessed, using 14 different concentrations, ranging from 0.03 to 60.0 mg Cu/L. The result indicated that short bath treatments at concentration s ranging from 42.0 to 60.0 mg Cu/L could kill the parasite, however, they might be toxic to the stressed grass carp. Concerning long bath treatments, it was found that the concentrations of 0.03, 0.06, 0.09, 0.12 and 0.15 mg Cu/L can eradicate the parasite after 120, 96, 48, 48 and 24 hours respectively. These subacute levels of the test compoumd showed no toxic effect on the grass carp.

Physicochemical Influences on Parasites of Age-0 Largemouth Bass in the Atchafalaya River Basin, Louisiana

ABSTRACT We investigated prevalence and intensity patterns of nine parasite taxa in 244 age-0 largemouth bass (Micropterus salmoides) collected from lake (high dissolved oxygen levels), riverine (high current velocities), and swamp (hypoxic canals and bayous) sites (N=6) in the Atchafalaya River Basin during the 1996 flood pulse. Ectoparasites were dominated by monogenetic trematodes (prevalence=100%; median intensities 27–91 per host) and glochidia (prevalence > 96% at all sites, median intensities 47–148 per host), whereas Posthodiplostomum minimum (Trematoda), Caecincola spp. (Trematoda; C. parvulus and perhaps C. latostoma), Neoechinorhynchus cylindratus (Acanthocephala), and Proteocephalus ambloplitis (Cestoda) accounted for 94.6% of bass endoparasites. Overall, lake sites supported the highest median parasite intensities in bass and most highly parasitized individuals. P. minimum was prevalent in bass collected from all sites, but intensities were highest in bass from lake habitats. In contrast, P. ambloplitis exhibited lower than expected prevalence in bass from lake sites (P. < 0.05) and higher intensity (P < 0.02) in bass from riverine sites. Patterns of parasite abundance appeared to be related to habitat effects on intermediate host and parasite life-cycle dynamics rather than hypoxia-related suppression of bass immune responses.

Gas bubble disease in farmed fish in Saudi Arabia

Four outbreaks of gas bubble disease were encountered among farmed fish in Saudi Arabia. Two of them occurred among subadult (52.5 g) saltwater tilapia (Oreochromis spilurus), the first affecting about...

Monogenetic trematodes from scombrid fishes of the Visakhapatnam coast, Bay of Bengal

In the course of a survey carried out on the monogenetic trematode fauna of 11 species of scombrid fishes collected from the Visakhapatnam coast, Bay of Bengal, 14 species of adult monogeneans were encountered. They are distributed over five families as follows: Capsalidae (2), Hexostomatidae (2), Mazocraeidae (3), Axinidae (1), and Gastrocotylidae (6). The species reported are Capsala katsuwoni, Capsala gouri, Hexostoma auxisi, Homostoma chura, Kuhnia indica, K. microlepidotusi, Indomazocraes jagannath, Uraxine chura, Eyelavera typica, Metapseudaxine ventrosicula, Gotocotyla secunda, G. bivaginalis, Pricea multae and Thoracocotyle indica. A number of taxonomic changes and synonymies are proposed.

Biologically Active Factors against the Monogenetic TrematodeGyrodactylus stellatusin the Serum and Mucus of Infected Juvenile English Soles

Length of survival of the monogenetic trematode Gyrodactylus stellatus in serum and mucus collected from English soles Pleuronectes vetulus at different stages of a laboratory epizootic suggests that both the mucus and serum may be involved in resistance to the parasite. In general, trematode survival was shorter in the serum and mucus samples collected from English soles at the later, recovering stages of infection. A rabbit antiserum against English sole whole serum was used in a gel diffusion immunoassay to show that mucus from infested English soles contained proteins antigenically similar to English sole serum proteins. Precipitation reactions appeared strongest in mucus collected during later stages of infection. No precipitation reactions were detected in the mucus of uninfested fish, indicating that the precipitation bands that were observed were associated with G. stellatus infections.

Studies on the enzyme phenol oxidase in a freshwater monogenetic trematode

AbstractCytochemical localization of the enzyme phenol oxidase inNeomurraytrema tengrahas been studied. Results reveal that the enzyme reacts with substrates such as catechol, hydroquinone, pyrogallol, dopa, doparmine, epinephrine and tyramine, but not with tyrosine and protocatechuic acid. Thus it shows activity with a wide range of phenols, aminated, mono and diphenols and also with deaminated and decarboxylated, di- and polyphenols. The maximum activity of the enzyme occurs between 40°C and 50°C with a pH optimum of 6–6.

Host-Parasite Relationships between Gyrodactylus stellatus (Monogenea: Gyrodactylidae) and Parophrys vetulus (Pleuronectidae: English Sole) from Coastal Waters of Oregon

Gyrodactylus stellatus Crane and Mizelle, 1967, was found on juvenile English sole (Parophrys vetulus), speckled sanddabs (Citharichthys stigmaeus) and starry flounder (Platichthys stellatus) in Yaquina Bay, Oregon. Prevalence and intensity of infections were higher on juvenile English sole than on speckled sanddabs or starry flounders. Over a 12-mo period from July 1981 to June 1982, prevalence and intensity of infection on juvenile English sole averaged 69.2% per sampling and 5.5 worms per fish, respectively. Prevalence and intensity were maximum in June (98.0% and 10.1 worms/fish) and minimum in October (37.0% and 1.7 worms/ fish). In the laboratory, intensity on juvenile English sole reached higher levels than observed on hosts in the estuary. Intensity increased for 9 wk then decreased over the next 3-wk period. Rate of G. stellatus population growth increased with temperature from 6 to 18 C, and was higher on unfed than on fed English sole. Salinity and previous experience with high infection levels did not significantly influence the rate of G. stellatus increase. English sole (Parophrys vetulus Girard, 1854) is one of the most common pleuronectid species found along the Pacific Coast of the United States and an important component of the commercial fishery (Hart, 1973). Large numbers of juvenile English sole utilize Yaquina Bay as a nursery ground during their first year of life (Olson and Pratt, 1973) and according to Olson (1978) are commonly parasitized by Gyrodactylus stellatus Crane and Mizelle, 1967. Gyrodactyliasis caused by several species of monogenetic trematodes in this genus has been reported in both freshwater and marine teleosts (Cone and Odense, 1984). This study examines the host-parasite relationship between English sole and G. stellatus. MATERIALS AND METHODS Fishes from Yaquina Bay, Oregon were collected with a 5-m otter trawl and transported to the Oregon State University Marine Science Center. Juvenile English sole (P. vetulus) to be used in experiments were held in circular tanks (87 cm in diameter with 125 L of seawater) supplied with running ultraviolet light filtered seawater (3-4 L/min) for 1-2 wk to allow feeding to begin. Experimental fish were of similar size (7.5 + 3.2 cm long) and free of abnormalities. All fish were maintained on a diet of commercial moist salmon feed. Uninfected experimental fish were obtained by treating with a 1:4,000 formalin solution for 1 hr (Putz and Hoffman, 1963). Laboratory infections were produced by placing uninfected fish in a tank with 2-3 infected fish for 1-3 days. Received 16 April 1985; revised 27 September 1985; accepted 30 September 1985. Host specificity of G. stellatus was studied ecologically by examining a variety of potential host species from Yaquina Bay and experimentally by exposing potential hosts to the parasite in the laboratory. Prevalence and intensity of infection of G. stellatus on English sole from Yaquina Bay by season and by size of fish were determined from samples taken monthly from July 1981 to June 1982. Shortly after capture, 50 fish were selected randomly and the number of Gyrodactylus present on the fins of each fish was counted under a dissecting microscope. If the catch was less than 50 fish, all were used as samples. The method by which G. stellatus transfers from one host to another was examined in an experiment that consisted of 4 treatments. In the first and second treatments infected English sole were kept separate from uninfected hosts in flowing and static water. In the third treatment, infected and uninfected fish were allowed direct contact in static water. In the last treatment infected English sole were removed from the container before introduction of uninfected sole. Each container contained 2 infected and 3 uninfected English sole. The rate at which G. stellatus increased in number on juvenile English sole (8.8 ? 1.08 cm long) under laboratory conditions and ambient temperature was determined by following the course of infection on 50 naturally infected individuals. The number of worms on pectoral, ventral and caudal fins on each fish was counted weekly for 1 yr. To determine the effect of temperature on intensity of infection, naturally infected English sole were held in circular tanks of running seawater maintained at 6, 12, or 18 C. Each treatment was replicated with 25 fish (10.3 ? 1.12 cm long) per replicate. The experiment extended for 6 wk and the number of G. stellatus per fish was counted weekly. In an experiment to determine the effect of salinity on intensity of G. stellatus infections, infected fish (10.1 + 0.62 cm long) were maintained at salinities of 14, 21 and 28%o in static water.

フタゴムシの生殖年周期に関する研究 Ｉ フタゴムシＤｉｐｌｏｚｏｏｎ ｎｉｐｐｏｎｉｃｕｍの非産卵期における生殖器官について

The reproductive organs of a monogenetic trematode, Diplozoon nipponicum, were histologically observed during non-spawning period, from November 1982 to April 1983. The parasites were taken from the gill of common crucian carp Carassius auratus subsp. and C. auratus langsdorft caught in the Hirai and Aki River of the Tama River water system. The parasites were observed in all months examined. Even during non-spawning period, oocytes and spermatozoa were in their gonads, whereas yolk cells in the vitelline glands distinctly decreased both in size and number with the decline of water temperature. These results indicate that, in gonadal maturation, the development of vitel-line glands is most clearly affected by water temperature among the reproductive organs.

Progress in Medical Virology

In 1966, the senior author of this volume published the first edition of this treatise. It was well received by parasitologists and comparative physiologists. This second edition essentially follows the same format as the first. It consists of 13 chapters. After discussing the general biology of digenetic trematodes very briefly in the first chapter, the authors consider the functional morphology of the various systems and the ingestion and digestion processes of these parasites in the following two chapters. In Chapter 4 the metabolism of adult trematodes is considered, while Chapters 5 through 7 consider aspects of the physiology of the egg, intramolluscan stages, and the cercaria. In Chapter 8 development of digeneans within the definitive host is considered, while Chapter 9 reviews available techniques for culturing worms.In Chapters 10 through 12 the morphology and physiology of the aspidogastrean and monogenetic trematodes are considered. Finally, Chapter 13 considers immunity to trematode infections, especially schistosomiasis and fascioliasis.