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Mixed Infections and Hybridisation in Monogenean Parasites  [PDF]
Bettina Schelkle, Patricia J. Faria, Mireille B. Johnson, Cock van Oosterhout, Joanne Cable
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0039506
Abstract: Theory predicts that sexual reproduction promotes disease invasion by increasing the evolutionary potential of the parasite, whereas asexual reproduction tends to enhance establishment success and population growth rate. Gyrodactylid monogeneans are ubiquitous ectoparasites of teleost fish, and the evolutionary success of the specious Gyrodactylus genus is thought to be partly due to their use of various modes of reproduction. Gyrodactylus turnbulli is a natural parasite of the guppy (Poecilia reticulata), a small, tropical fish used as a model for behavioural, ecological and evolutionary studies. Using experimental infections and a recently developed microsatellite marker, we conclusively show that monogenean parasites reproduce sexually. Conservatively, we estimate that sexual recombination occurs and that between 3.7–10.9% of the parasites in our experimental crosses are hybrid genotypes with ancestors from different laboratory strains of G. turnbulli. We also provide evidence of hybrid vigour and/or inter-strain competition, which appeared to lead to a higher maximum parasite load in mixed infections. Finally, we demonstrate inbreeding avoidance for the first time in platyhelminths which may influence the distribution of parasites within a host and their subsequent exposure to the host's localized immune response. Combined reproductive modes and inbreeding avoidance may explain the extreme evolutionary diversification success of parasites such as Gyrodactylus, where host-parasite coevolution is punctuated by relatively frequent host switching.
Molecular characterisation of Babesia gibsoni infection from a Pit-bull terrier pup recently imported into South Africa  [cached]
P.T. Matjila,B.L. Penzhorn,A.L. Leisewitz,R. Bhoora
Journal of the South African Veterinary Association , 2012, DOI: 10.4102/jsava.v78i1.277
Abstract: Canine babesiosis caused by Babesia gibsoni was diagnosed in a 3-month-old Pit-bull pup during a routine clinical examination. Diagnosis was confirmed by way of smear examination, PCR, Reverse Line Blot (RLB) and sequence analysis which showed 100% homology with B. gibsoni (Japan AB118032) and Babesia sp. (Oklahoma) (AF205636). Haematology showed moderate anaemia and severe thrombocytopenia. Treatment was initiated with diminazene aceturate (Berenil RTU(R) followed by 2 doses of imidocarb diproprionate (Forray-65(R) 3 days and 14 days later, respectively. Babesia gibsoni DNA was still detectable 2 weeks post-treatment on the PCR/RLB test. A 10-day course of combination drug therapy using atovaquone and azithromycin was initiated. Blood samples taken on Day 1 and Day 40 after completion of treatment were negative for B. gibsoni DNA on PCR/RLB test. The implications of a possible introduction of B. gibsoni into South Africa are discussed.
Pseudohaliotrema paralonchuri sp.n. (Monogenoidea: Dactylogyridae), parasitic on Paralonchurus peruanus (Steindachner) (Teleostei: Sciaenidae) from the peruvian coast
Luque, Jose Luis;Iannacone, Jose;
Memórias do Instituto Oswaldo Cruz , 1989, DOI: 10.1590/S0074-02761989000400012
Abstract: pseudohaliotrema paralonchuri sp. n., parasitic on the sciaenid fish paralonchurus peruanus (steindachner) from the peruvian central coast, is described, illustrated and compared with related species of the genus. p. paralonchuri differs from other pseudohaliotrema by the characteristics of the cirrus, accessory piece, anchors and bars. this is the first record of pseudohaliotrema from the south american pacific ocean.
On some family related parasites (Nematoda, Cucullanidae) from the marine fish Paralonchurus brasiliensis (Steindachner, 1875) (Pisces, Ostraciidae)
Pinto, R. Magalh?es;Vicente, J. Julio;Noronha, Dely;
Memórias do Instituto Oswaldo Cruz , 1992, DOI: 10.1590/S0074-02761992000500039
Abstract: dichelyne (cucullanellus) elongatus (tornquist, 1931) petter, 1974 and cucullanus pulcherrimus barreto, 1918, from paralonchurus brasiliensis (steind., 1875) are redescribed and two specimens of dichelyne (cucullanellus) sp. are also reported in this host, despite lack of previously, was again identified in brazil since its original description and posterior illustration. the present findings represent also a new host record for the referred genera: dichelyne jagerskiold, 1902 and cucullanus mueller, 1777. d. (c.) elongatus is also referred in brazil for the first time.
Morfometria comparada de Ctenosciaena gracilicirrhus, Paralonchurus brasiliensis e Micropogonias furnieri (Teleostei: Sciaenidae) pela análise multivariada de redes de treli?as
Cavalcanti, Mauro José;Lopes, Paulo Roberto Duarte;
Revista Brasileira de Zoologia , 1990, DOI: 10.1590/S0101-81751990000400016
Abstract: comparative morphometrics of ctenosciaena gracilicirrhus, paralonchurus brasiliensis and micropogonias furnieri (teleostei: sciaenidae) by multivariate analysis of truss networks. morphological differentiation among three species of sciaenid fishes, ctenosciaena gracilicirrhus, paralonchurus brasilliensis and micropogonias furnieri, was analyzed by multivariate statistical techniques, using measuraments obtained from truss networks based on anatomical landmarks. principal components analysis of interlandmark distances defined by the truss system showed that the individuais of ctenosciaena gracilicirrhus are different from those of the other two species in relation to shape, being more similar to the individuals of micropogonias furnieri in relation to size.
Use of a doxycycline-enrofloxacin-metronidazole combination with/without diminazene diaceturate to treat naturally occurring canine babesiosis caused by Babesia gibsoni
Ming-Yu Lin, Hui-Pi Huang
Acta Veterinaria Scandinavica , 2010, DOI: 10.1186/1751-0147-52-27
Abstract: Canine babesiosis is an important worldwide, tick-borne disease caused by hemoprotozoan parasites of the genus Babesia, and the predominant species infecting dogs is B. vogeli [1]. In a previous study, B. gibsoni was found to be the major causative agent of canine babesiosis in Taipei, Taiwan [2]. Babesia gibsoni is a small pleomorphic, intraerythrocytic parasite that can cause erythrocyte destruction and hemolytic anemia [1]. This parasite is suspected to be transmitted through the bite of ixodid ticks, such as Rhipicephalus sanguineus [1,3-8].Clinical signs of canine babesiosis are characterized by lethargy, anorexia, fever, hemolytic anemia, thrombocytopenia, splenomegaly and even septic shock [2,9-14]. Chronic infection is common. Definitive diagnosis of canine babesiosis is based on medical history and clinical signs together with the identification of Babesia spp. within infected erythrocytes, positive serologic results, and detection of amplification of nucleic acid extracted from blood or tissues [4,5,15].Many drugs have been applied in management of canine babesiosis, including babesiacidal agents (diminazene aceturate, imidocarb diproprionate), antibiotics (azithromycin, clindamycin, doxycycline, metronidazole), and an antiprotozoal agent (Atovaquone). However, no single drug has successfully eliminated B. gibsoni from infected dogs [9,10,12,13,15-18]. Addictive or synergistic effects of these drugs in combination have not been fully evaluated. The babesiacide diminazene diaceturate is mainly used in horses, donkeys and cows [19-21]. Efficacy of diminazene diaceturate in management of canine babesiosis is limited, but this is the only diminazene available for veterinary use in Taiwan, whereas atovaquone is not yet available. The aim of this study was to evaluate the efficacy of a doxycycline-enrofloxacin-metronidazole (D-E-M) combination with and without administration of diminazene diaceturate to manage naturally occurring canine babesiosis caused by B. g
Biologia de Paralonchurus brasiliensis (Steindachner) (Teleostei, Sciaenidae) no litoral sul do Estado do Paraná, Brasil
Robert, Maurício de C.;Michels-Souza, Maria A.;Chaves, Paulo de T.;
Revista Brasileira de Zoologia , 2007, DOI: 10.1590/S0101-81752007000100024
Abstract: the populational structure, reproduction and feeding features of banded croaker in southern coast of paraná state are presented. samplings were performed through bottom trawl from march 1999 to january 2000 at depths 10 and 15 m. paralonchurus brasiliensis is more abundant during spring, when the youngest individuals, smaller than 93 mm, are recruited. the relation weight/length for grouped sexes is tw(g) = 2.74e-6tl(mm)3.22 (n = 659; r2 = 0.99). gonadal maturation is recorded since the length class 130-165 mm and the average length of the first maturation (grouped sexes) is estimated in 175 mm. sand worms (polychaeta) are the feeding item more usual for the all size classes and seasons, followed by crustacean and fishes. species reproductive period extends from autumn (start maturation) to summer (end the spawning). after spring, youngs probably leave the area 10 m of depth. the prohibition of the shrimp bottom trawl in this depth during the spring and the summer must be efficient to reduce p. brasiliensis by-catch, today composed by recruits or spawning proximity individuals.
Fauna of monogenean trematodes-parasites of some cyprinid fishes from lake Prespa, Macedonia
Stojanovski S.,Kuli?i? Zoran,Baker Ra,Hristovski N.
Acta Veterinaria , 2004, DOI: 10.2298/avb0401073s
Abstract: During parasitological investigations six species of monogenean trematodes were found on the gills of three cyprinid fish species from Lake Prespa (Macedonia), as follows: Dactylogyrus prostae and Dactylogyrus sphyrna in Leuciscus cephalus albus, Dactylogyrus erhardovae, Dactylogyrus sphyrna and Paradiplozoon zeller in Rutilus rubilio prespensis and Dactylogyrus elegantis and Dactylogyrus vistulae in Chondrostoma nasus prespensis. The prevalence in Leuciscus cephalus albus was 62.22%, in Rutilus rubilio prespensis 59.87% while in Chondrostoma nasus prespensis it was the lowest and amounted to 41.59%. The overall, prevalence of monogeneans in the investigated cyprinid fishes from Lake Prespa was 53.65%, and the mean intensity of infestation was 6.08. Among the monogenean species the highest prevalence occurred with Dactylogyrus sphyrna (25.08%), and the greatest intensity of infestation was evident in the cases of infestation with Dactylogyrus erhardovae (12.87). The greatest pathological effect was associated with the monogeneans Dactylogyrus vistulae and Paradiplozoon zeller. All monogenean species found represented the first record for such parasite fauna of fishes in Macedonia.
Effects of Water Quality and Monogenean Parasite in the Gills of Freshwater Cat Fish, Hemibagrus nemurus Valenciennes 1840  [cached]
B.M. Modu,M. Saiful,M. Kartini,Zaleha Kasim
Current Research Journal of Biological Sciences , 2012,
Abstract: The Study on Hemibagrus nemurus (Valenciennes, 1840) gills was designed to investigate the influence of monogenean irritation coupled with water quality condition of the pond (earthen pond) in Perlok, Pahang. Three hundred and eighty fish host were examined, their gills were excised and fixed in 3% glutaraldehyde for scanning electron microscopy and in bouin’s solution for histology. In the infected fish gills, the pathological alterations observed such as proliferative, degenerative and necrotic changes in the epithelium of gill filaments. In the secondary lamellae, telangiectasia, fusion of secondary lamellae and excessive mucous cells proliferation were observed. Correlation was made between water quality parameters and intensity of monogenean infestation in the ponds. It can be concluded that gill alterations as a result of monogeneans irritation and poor water quality in fish ponds may serve as a sensitive biomarker for pollutants.
The Monogenean Parasite Fauna of Cichlids: A Potential Tool for Host Biogeography  [PDF]
Antoine Pariselle,Walter A. Boeger,Jos Snoeks,Charles F. Bilong Bilong,Serge Morand,Maarten P. M. Vanhove
International Journal of Evolutionary Biology , 2011, DOI: 10.4061/2011/471480
Abstract: We discuss geographical distribution and phylogeny of Dactylogyridea (Monogenea) parasitizing Cichlidae to elucidate their hosts' history. Although mesoparasitic Monogenea (Enterogyrus spp.) show typical vicariant distribution, ectoparasitic representatives from different continents are not considered sister taxa, hence their distribution cannot result from vicariance alone. Because of the close host-parasite relationship, this might indicate that present-day cichlid distribution may also reflect dispersal through coastal or brackish waters. Loss of ectoparasites during transoceanic migration, followed by lateral transfer from other fish families might explain extant host-parasite associations. Because of its mesoparasitic nature, hence not subject to salinity variations of the host's environment, Enterogyrus could have survived marine migrations, intolerable for ectoparasites. Host-switches and salinity transitions may be invoked to explain the pattern revealed by a preliminary morphological phylogeny of monogenean genera from Cichlidae and other selected Monogenea genera, rendering the parasite distribution explicable under both vicariance and dispersal. Testable hypotheses are put forward in this parasitological approach to cichlid biogeography. Along with more comprehensive in-depth morphological phylogeny, comparison with molecular data, clarifying dactylogyridean evolution on different continents and from various fish families, and providing temporal information on host-parasite history, are needed to discriminate between the possible scenarios. 1. Introduction: Explanations to the Current Distribution Pattern of Freshwater Fish Groups Organisms with limited dispersal abilities are generally considered to be useful tools in historical biogeography. Examples include amphibians [1] and freshwater fishes [2, 3]. At the heart of many discussions on the evolutionary history and distribution patterns of major freshwater fish groups is the vicariance versus dispersal debate (e.g., [4, 5]). Although vicariance-based scenarios have classically been favoured, de Queiroz [6] gives an overview of how the importance of (often seemingly unlikely) dispersal events has been underestimated in historical biogeography, though his examples stem mostly from plants and terrestrial biota. It is generally accepted that the distribution of several ancient freshwater groups such as Dipnoi (lungfishes) and Osteoglossiformes (bony tongues) results from major vicariant events after the breakup of Gondwana [7]. However, because of conflicting evidence, the discussion continues
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