ABSTRACT
Three new sequences of Mitochondrial cytochrome c-oxidase subunit 2 (mtDNA cox-2) from C. pelagicum parasite of Spheniscus magellanicus, the Magelanicus penguin, were determined from Brazilian waters. The sequences presented 99 and 98% of similarity with C. pelagicum sequences from Argentina, deposited on GenBank for the same genetic region and with a strong statistical support inferred from the phylogenetic tree. The morphological and ultrastructural studies that were carried out confirmed the genetic analysis.
Subject(s)
Ascaridoidea/anatomy & histology , Ascaridoidea/genetics , Spheniscidae/parasitology , Animals , Ascaridoidea/physiology , Base Sequence , Brazil , DNA, Mitochondrial/analysis , Electron Transport Complex IV/genetics , Female , MaleABSTRACT
BACKGROUND: Melanoides tuberculatus (Müller, 1774) (Thiaridae), an introduced gastropod mollusc with a wide geographical distribution in the Neotropics, is the intermediate host of the trematode Centrocestus formosanus (Nishigori, 1924) (Heterophyidae). This parasite is considered to be pathogenic to humans. The aim of the present work was to evaluate the locomotory activity of uninfected M. tuberculatus compared with those naturally infected with C. formosanus. FINDINGS: The locomotory activity of each mollusc was recorded using an image analysis biomonitoring system, Videomex-V, to evaluate and quantify the parameters of 'Stereotypic' and 'Resting time'. The Generalized Estimating Equation analysis of locomotory activity of M. tuberculatus infected with C. formosanus revealed significant differences compared with uninfected molluscs for the parameters 'Stereotypic time' and 'Resting time' with a reduction of movement. The variations in the values of the monitoring intervals recorded showed a significant difference for the infected molluscs in the case of Stereotypic time, with an irregular locomotory activity pattern, as compared to that of uninfected molluscs. The analysis of the standard length of all molluscs did not exhibit any correlation with locomotory activity, showing that C. formosanus is able to alter the locomotory activity of its snail host regardless of the standard length. CONCLUSIONS: The trematode C. formosanus affects the locomotory activity of the mollusc M. tuberculatus by reducing its movement and causing it to exhibit an irregular pattern of activity, both of which are independent of the snail's standard length.
Subject(s)
Heterophyidae/pathogenicity , Mollusca/physiology , Mollusca/parasitology , Animals , Biological Assay/methods , Image Processing, Computer-Assisted/methods , Locomotion , Trematode Infections/parasitology , Trematode Infections/pathologyABSTRACT
Owing to the veterinary and medical importance of heterophyid trematodes, a survey on Ascocotyle (Phagicola) longa in different organs of mullets Mugil liza from Rio de Janeiro was undertaken. The prevalence of metacercariae varied greatly between different organs of the mullets: spleen (100%), heart (98%), intestine wall (97%), liver (97%), muscle (87%), stomach wall (77%), brain (47%), gonads (30%) and gall bladder (30%). The high level of the intensity of the infection in relation to different fish organs was confirmed in two experimental infections performed during the spring/summer and autumn/winter seasons when 258 and 47 adult parasites were recovered from hamsters fed only with small pieces of muscle tissue. The potential risk of infection was considered to be high in view of the high prevalence and intensity of A. (P.) longa in the muscles of mullets throughout the year. Additionally new confocal imaging of metacercariae and adults experimentally obtained, enabled for the first time the description of a short genital atrium formed by the union of uterus and ejaculatory duct.
Subject(s)
Fish Diseases/parasitology , Trematoda/classification , Trematode Infections/veterinary , Animals , Brazil/epidemiology , Cricetinae , Fish Diseases/epidemiology , Fishes , Muscle, Skeletal/parasitology , Prevalence , Risk Factors , Trematode Infections/epidemiology , Trematode Infections/parasitologyABSTRACT
Satanoperca jurupari (Osteichthyes: Cichlidae) is reported for the first time to be parasitized by the nematodes Procamallanus (Spirocamallanus) rarus Travassos, Artigas and Pereira, 1928, Procamallanus (Spirocamallanus) sp., larvae of Raphidascaroides sp. and Anisakidae gen. sp., and by the acanthocephalan Neoechinorhynchus (Neoechinorhynchus) paraguayensis Machado Filho (Rev Bras Biol 19:379-381, 1959).
Subject(s)
Cichlids/parasitology , Fish Diseases/parasitology , Parasitic Diseases, Animal/parasitology , Acanthocephala/isolation & purification , Animals , Brazil , Nematoda/isolation & purificationABSTRACT
Raphidascaris (Sprentascaris) lanfrediae sp. nov. is described from the intestine of the freshwater fish Satanoperca jurupari (Heckel) (Cichlidae) from the Guamá River, state of Pará, Brazil. The prevalence in fish (n = 59) was 27% with intensity of one-124 (mean 16) nematodes per fish. The new species is characterized mainly by the markedly larger size of ventricular appendix in relation to the oesophagus, presence of short male caudal alae, 14-16 subventral pairs of preanal papillae and six pairs of postanal papillae.
