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1.
Dis Aquat Organ ; 144: 55-59, 2021 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-33704092

RESUMO

We report hirudiniasis caused by the leech Hemiclepsis marginata asiatica Moore, 1924 in albino red-bellied pacu (pirapitinga) Piaractus brachypomus (Cuvier, 1818), constituting the first documentation of a freshwater fish species being affected in India. The outbreak occurred in a tank of an aquarium-fish retailer; infested fish appeared asphyxiated, unable to swim or swimming upside down, with cloudy eyes and body with thick mucus secretion. The prevalence and mortality was 100%, with a mean intensity of 81 leeches per fish. The histopathology of the morbid fish revealed degenerative necrosis, eosinophilic infiltration in the muscle tissue and haemorrhages in the fin membrane. The leech mitochondrial 18S rDNA and 12S rDNA genes were characterised and submitted to GenBank under accession numbers MN380443 (18S) and MK733282 (12S). A maximum likelihood tree was constructed using 12S rDNA gene sequences to demonstrate the phylogenetic position of Hemiclepsis marginata asiatica among its congeners.


Assuntos
Caraciformes , Sanguessugas , Animais , Surtos de Doenças/veterinária , Índia , Filogenia
2.
Braz J Biol ; 82: e232868, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33681896

RESUMO

The "piaussu", Megaleporinus macrocephalus is an anostomatid fish species native to the basin of the Paraguay River, in the Pantanal biome of western Brazil. However, this species has now been recorded in a number of other drainages, including those of the upper Paraná, Uruguay, Jacuí, Doce, Mucuri, and Paraíba do Sulrivers. This study presents two new records of the occurrence of M. macrocephalus, in the basins of the Itapecuru and Mearim rivers in the state of Maranhão, in the Brazilian Northeast. The piaussu is a large-bodied fish of commercial interest that is widely raised on fish farms, and its occurrence in the Itapecuru and Mearim rivers is likely the result of individuals escaping from fish tanks when they overflow during the rainy season. Morphological analyses and sequences of the Cytochrome Oxidase Subunit I (COI) gene confirmed the taxonomic identification of the specimens as M. macrocephalus. The COI sequences were 99.66% similar to those of M. macrocephalus deposited in the BOLDSystems database. These records extend the known distribution of M. macrocephalus to the basins of the Itapecuru and Mearim rivers in the Brazilian Northeast, highlighting a new case of introduction of exotic fish species into Brazilian river basins.


Assuntos
Caraciformes , Rios , Animais , Brasil , Caraciformes/genética , Humanos , Paraguai , Uruguai
3.
Braz J Biol ; 82: e232612, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33787711

RESUMO

Three experiments were done with different particle sizes of corn feed on its zootechnical performance, passing rate and apparent digestibility of juvenile tambaqui (Colossoma macropomum). In the first, 200 juveniles were used and distributed in 20 tanks (220 L), 10 fish per unit (four replicates). The experimental system used to record passage time was composed of five incubators with 200 L. In the second, 75 juveniles were used per 55 days (three replications). In the third, 75 juveniles were used and distributed in five incubators of 200 L. All experiments were performed randomly. Different linear behavior treatments were observed for apparent digestibility of crude protein; and the smaller particle size (150 µm) had better results digestibility. smaller particle size of the corn had better results, affected the growth performance of tambaqui and the apparent digestibility of crude protein and ether extract. Thus, is recommended that a particle size of 150 µm of corn be used for tambaqui.


Assuntos
Caraciformes , Zea mays , Ração Animal/análise , Animais , Dieta/veterinária , Tamanho da Partícula
4.
Aquat Toxicol ; 231: 105734, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33385846

RESUMO

Several studies have suggested eugenol as a suitable anaesthetic for fish. However, it has also been regarded as a toxic and aversive substance to several aquatic organisms, including fish. This study sought to assess the eugenol-induced behavioural alterations and its seizurogenic potential to fish. Moreover, a distinctive methodology for an in vivo evaluation of the brain activity was also presented. Prior to the evaluation of eugenol-induced responses, fish were exposed to pentylenetetrazole (PTZ), to characterize any seizure-like patterns. Antagonizing responses to PTZ were assessed in fish receiving diazepam (BDZ) and subsequently exposed to PTZ. Tambaqui fish juveniles, Colossoma macropomum (15.8 ± 2.8 g) were used as models and assayed as follows: (i) fish exposed to PTZ (15 mM) and (ii) fish receiving a dose of BDZ (10 mg Kg-1) and later exposed to PTZ (15 mM) (BDZ-PTZ group). Thereafter, fish were evaluated throughout (iii) eugenol exposure at 65 µL L-1 (ethanolic solution) and recovery. Control fish and a vehicle control group (ethanol at 585 µL L-1) were also established. PTZ baths elicited body immobilization preceded by hyperactivity in a stereotyped seizure-like behaviour with increased EEG wave amplitude and frequency. PTZ effects in the brain were attenuated by a pre-administration of BDZ. Upon eugenol exposure, tambaqui had an intense neuronal excitability, showing a clonus-like seizure behaviour, also corroborated by the EEG patterns, which were consistent with a seizure-like response. Responses of eugenol-exposed fish resembled those of the PZT-exposed animals, with epileptiform discharges. EMG was in line with the EEG modulation, showing increased tracing oscillations and higher mean amplitudes in PTZ-exposed fish whereas in BDZ-PTZ group muscle contraction was less frequent and powerful. Fish exposed to eugenol showed initially some muscle activity followed by a loss of muscle tonus over time. In summary, our results showed that upon eugenol exposure, although a time-dependent body immobilization was attained, fish presented an intense neuronal excitability comparable to that evoked by PTZ. Eugenol failed to promote depression of the CNS and therefore may be not suitable to be used for general anaesthesia of C. macropomum. As eugenol could be implicated in seizurogenesis and be potentially toxic to the fish brain, protocols suggesting the broad use of eugenol for short-term anaesthesia or euthanasia of fish should be carefully revised, as it raises important concerns in terms of ethics and fish welfare.


Assuntos
Caraciformes/fisiologia , Eugenol/toxicidade , Imobilização , Neurônios/patologia , Animais , Comportamento Animal/efeitos dos fármacos , Encéfalo/diagnóstico por imagem , Encéfalo/efeitos dos fármacos , Eletrodos , Eletroencefalografia , Eletromiografia , Fenômenos Eletrofisiológicos , Masculino , Músculos/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Pentilenotetrazol/toxicidade , Poluentes Químicos da Água/toxicidade
5.
Mar Pollut Bull ; 160: 111637, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33181924

RESUMO

This study reports on the ingestion of microplastics by the alien fish Pirapitinga, Piaractus brachypomus (Characiformes; Serrasalmidae) that escaped Vembanad lake, the largest brackish water lake in the south-west coast of India, from the aquaculture systems during flooding. Microplastics separated from the gut of 32 out of the 123 fishes (26%) examined were identified using Attenuated Total Reflectance - Fourier Transform Infrared (ATR-FTIR), and Raman Spectroscopy. In total, 69 microplastic particles, represented by fibers, foam and fragments were recovered from the fish, with sizes ranging from 0.89 to 4.85 mm. The ATR-FTIR spectral analyses revealed the presence of polymers polyethylene and Nylon 6. The occurrence of PP, Nylon 6, PET and PBT were confirmed using Raman spectroscopy. The presence of MPs in the gut content of alien fish P. brachypomus could be a reflection of the increasing microplastics pollution in the estuaries and backwaters along the south-west coast of India.


Assuntos
Caraciformes , Poluentes Químicos da Água , Animais , Monitoramento Ambiental , Peixes , Índia , Espécies Introduzidas , Lagos , Microplásticos , Plásticos , Poluentes Químicos da Água/análise
6.
An Acad Bras Cienc ; 92(suppl 2): e20180721, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33146270

RESUMO

This study aimed to describe the occurrence, morphology and prevalence of Spirocamallanus krameri, a parasite of Hoplerythrinus unitaeniatus collected in state of Pará, Brazil. The morphological and morphometric characteristics are consistent with the species S. krameri, by having a hexagonal mouth opening, 16 cephalic papillae and two lateral papillae on the amphids. The buccal capsule is internally different in both sexes, with (11-13) spiral ridges in males and (13-17) spiral ridges in females. The basal ring is well developed, and three teeth are present in males and absent in females. Ten sessile caudal papillae and a pair of phasmidial pores occur in males. The spicules are small, subequal, 81-101 µm in length and the tail is tapered. The vulva in females is postequatorial, the tail is conical with lateral phasmidial pores. Among the species of Spirocamallanus that have short spicules, the general morphology of S. krameri most resembles that of S. inopinatus, but differs from that species, which have two cephalic teeth visible (absent in S. krameri) and specimens of S. inopinatus do not have sexual dimorphism in the buccal capsule of present in S. krameri.


Assuntos
Caraciformes , Nematoides , Animais , Brasil , Feminino , Masculino
7.
An Acad Bras Cienc ; 92(3): e20190099, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33111818

RESUMO

The aim of this study was to evaluate the growth curve of selectively bred and non-selectively bred tambaqui (Colossoma macropomum). The experiment involved 388 fish (weight: 65.38 ± 20.00 g; age: 217 days), consisting of 252 fish from seven selectively bred families (18 fish per family) and 18 non-selectively bred fish (control group). Groups were placed in two 800-m² tanks. Biometric measurements were taken on nine occasions at 30-day intervals, for a period of 254 days. Weight and morphometric traits were evaluated. To describe the tambaqui growth behavior, we adopted the Gompertz nonlinear regression model. Greater growth (p < 0.05) was observed in selectively bred families compared with control group. Four families stood out with higher (p < 0.05) asymptotic values for weight (F1: 2448.7 g; F7: 2284.7 g; F5 2180.1 g; F4: 2080.5 g; and control: 1808.4 g) and other morphometric traits. None of the selectively bred families (except F5) had a higher growth rate and age at inflection point than the fish from control group. In conclusion, selectively bred and non-selectively bred fish present distinct growth curves, but some families have greatly superior growth.


Assuntos
Caraciformes , Animais , Cruzamento , Caraciformes/crescimento & desenvolvimento
8.
Zootaxa ; 4816(3): zootaxa.4816.3.5, 2020 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-33055693

RESUMO

A new species of Characidium is described from headwater tributaries of the upper rio Guaporé, Rio Madeira basin, Mato Grosso state, Brazil. The new species can be diagnosed from all congeners, except Characidium summus, for lacking the preorbital and postorbital stripes. It can be diagnosed from the latter species by having 12 circumpeduncular scales (vs. 14), by an adipose fin present (vs. adipose fin absent), and 10-12 bars along the body (vs. absence of bars), among other characters. The new species is so far only known from direct tributaries of the Rio Guaporé at the Serra da Borda, an isolated plateau 300-800 meters above sea level, and possess a behavior very uncommon within the genus, being a mid-water pelagic fish, instead of the benthic behavior of most congeners. Comments on the putative phylogenetic relationships of the new species, as well as some remarks on its unusual behavior within the genus, are presented.


Assuntos
Caraciformes , Distribuição Animal , Animais , Brasil , Filogenia , Água
9.
Zootaxa ; 4803(3): zootaxa.4803.3.3, 2020 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-33056005

RESUMO

A parasitological survey of fishes from two tributaries (Veados and Paranapananema Rivers) of the Jurumirim Reservoir, Upper Paranapanema River, São Paulo State, Brazil, was carried out a during a sampling survey in 2011 and 2012. Several ectoparasitic copepods were found inside the nostrils of the freshwater anostomid fish, Schizodon intermedius Garavello Britski, 1990. The morphological analysis of the copepod specimens indicated that they represent two species of the ergasilid genus Gamispatulus Thatcher Boeger, 1984: Gamispatulus schizodontis Thatcher Boeger, 1984 (type species) and an undescribed species, Gamispatulus ferrilongus n. sp., which are described herein. The present specimens of G. schizodontis agree in several respects with its original description; however, some differences were found regarding the morphology of mouthparts and the ornamentation of legs and antennules. These differences were not sufficient to propose a new species for this genus. However, it could indicate the need for reassessment of the type material to have a more complete representation of this species. Gamispatulus ferrilongus n. sp. shares several similarities with its congener G. schizodontis but the new species can be readily distinguished from its congener in having a unique combination of diagnostic features including: a long rostral spine with tip extending up to half of cephalothorax, simple retrostylets (lacking adjacent spatulate processes), and dorsal surface of genital double-somite with 2 rounded processes (anterior and posterior) on both lateral margins. A host-parasite list for all vaigamid genera and species is included.


Assuntos
Caraciformes , Copépodes , Doenças dos Peixes , Animais , Rios
10.
Zootaxa ; 4859(2): zootaxa.4859.2.6, 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33056200

RESUMO

A new species of Hyphessobrycon Durbin from the Paraná do Urariá system in Central Amazon region, Amazonas state, Brazil, is described. The new species is allocated into the Hyphessobrycon heterorhabdus species-group due to its color pattern, composed by a well-defined, horizontally elongated humeral blotch continuous with a conspicuous midlateral dark stripe that becomes blurred towards the caudal peduncle, and can be distinguished from all other species of the group by possessing humeral blotch and continuous midlateral stripe broad, occupying vertical height equivalent of two scale rows. A tricolored pattern composed dorsally by a red or reddish longitudinal stripe, a middle iridescent, golden or silvery longitudinal stripe, and ventrally by a variably-developed longitudinal dark stripe is identified as a putative additional character shared by the species of the Hyphessobrycon heterorhabdus species-group. The presence of bony hooks in all fins in mature males of some species of the Hyphessobrycon heterorhabdus species-group is also discussed.


Assuntos
Characidae , Caraciformes , Nadadeiras de Animais , Animais , Brasil , Masculino
11.
Zootaxa ; 4768(2): zootaxa.4768.2.6, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33056526

RESUMO

Characidium chancoense new species, is described from the transandean upper Río Cauca drainage in Colombia. It can be distinguished from all congeners by its pigmentation pattern that consists of 7-12 vertical bars, most of which are cuneate-shaped with the vertex ending on or just below the lateral-line scale series, except for the last 1-4, which are dorsoventrally elongate rectangular bars that extend well below the lateral line. Characidium chancoense is sympatric with C. caucanum Eigenmann, C. phoxocephalum Eigenmann, C. cf. zebra Eigenmann and C. cf. boavistae Steindachner. Unlike C. caucanum and C. cf. boavistae, C. chancoense does not appear to be sexually dimorphic.


Assuntos
Caraciformes , Animais , Aves , Colômbia , Drenagem , Cabeça
12.
Zootaxa ; 4790(3): zootaxa.4790.3.5, 2020 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-33056696

RESUMO

Characidium cacah, new species, apparently endemic to the rio das Velhas sub-basin, upper rio São Francisco basin, Brazil, is described. The new species is easily distinguished from congeners, except C. chicoi, C. helmeri, C. mirim, C. nana, C. nupelia, C. stigmosum and C. xavante, by having an incomplete lateral line and for lacking an adipose fin. The new species can be diagnosed from the aforementioned species by a series of characters, including the presence of 12 circumpeduncular scales, the isthmus completely scaled, a thin inconspicuous or dashed midlateral dark stripe, the absence of a conspicuous peduncular blotch, and humeral blotch and basicaudal spot variably marked.


Assuntos
Caraciformes , Animais , Brasil
13.
Zootaxa ; 4852(1): zootaxa.4852.1.1, 2020 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-33056706

RESUMO

Moenkhausia cotinho is redescribed based on the examination of meristic and morphometric data and external morphological characters of specimens from the Amazon and Orinoco basins and from rivers in the Guyana. The species is distinguished from congeners based on the combination of a reticulate color pattern, the presence of dark spots on the posterior edge of scales of the longitudinal rows dorsal to the lateral line, the presence of a dark blotch on the caudal-fin base failing to reach the posterior tip of the middle caudal-fin rays; the dorsal region of the eyes red to orange in life; 5/3 longitudinal series of scales, above and below the lateral line, respectively; and the tips of the pectoral-fin rays not extending beyond the base of the pelvic fin. All specimens of M. cotinho have a completely pored literal line except for a few specimens from drainages in the Guyana. The redefinition of the taxonomic limits and geographic distribution of M. cotinho allowed us to reevaluate the taxonomic limits and geographic distribution of Hemigrammus newboldi, the identity of which has been previously questioned, but which is clearly diagnosed from M. cotinho based on the relatively longer pectoral fin, the presence of conical teeth in the posterior portion of the dentary, the absence of a reticulate color pattern of body and in the shorter longitudinal dark stripe on body. In addition, two new species of Moenkhausia are described: Moenkhausia rondoni sp n. from the rio Madeira basin, Brazil and Moenkhausia pirahan sp n. from the lower rio Madeira and rio Trombetas and rio Tapajós basins, Brazil.


Assuntos
Characidae , Caraciformes , Animais , Rios
14.
Ecotoxicol Environ Saf ; 205: 111314, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32956866

RESUMO

Brazilian freshwater ecosystems are continuously exposed to pesticides and domestic sewage. The Uruguay River was chosen for this study because of its international importance, as it flows through Brazil, Argentina, and Uruguay. It receives contaminants such as pesticides and domestic residues. Thus, the aim of this study to assess the accumulation of pesticides in muscle of the fish Astyanax jacuhiensis, its biochemical responses, and the presence of pesticides in water. In total, seven pesticides were registered in water from both river sites. Eight pesticides were detected in fish muscle. The biochemical responses showed that brain lipid peroxidation (LPO) and protein carbonyl (PC) in A. jacuhiensis were higher in the summer. Muscle showed the highest LPO levels in the spring and the highest PC in the summer. Liver LPO and PC levels were higher in the spring and summer. In the gills, the PC was higher in the spring and the LPO in the spring and winter. In the brain and in the gills, glutathione-S-transferase activity was high in the summer and autumn. Catalase activity was lower during the winter and spring. Non-protein thiol (NPSH) levels were lower in the brain in the winter and spring. Muscle tissue showed lower NPSH in the winter (site 1). Liver NPSH showed increased levels in liver in the spring and winter (site 2). The biochemical results clearly is related to pesticides and/or to the presence of other contaminants in the water such as metals or domestic sewage. The accumulation of pesticides in fish muscle added evidence that pesticides have been used in the area surrounding the Uruguay River. In conclusion, the biomarkers assayed in the present study could be used in future investigations considering other sampling sites along Uruguay River.


Assuntos
Characidae/fisiologia , Monitoramento Ambiental , Praguicidas/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores/metabolismo , Brasil , Characidae/metabolismo , Caraciformes/metabolismo , Caraciformes/fisiologia , Ecossistema , Brânquias/metabolismo , Peroxidação de Lipídeos , Metais/metabolismo , Praguicidas/análise , Rios/química , Estações do Ano , Poluentes Químicos da Água/análise
15.
Ecotoxicol Environ Saf ; 205: 111340, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32966934

RESUMO

The increase in pesticide use in response to agricultural demands poses a risk to non-target organisms, including fish. Integrated analysis of biochemical, histopathological and genetic parameters in fish exposed to Malathion insecticide provide information on the toxicity mechanisms of this pesticide, which is classified as a probable carcinogen for humans. The present study assessed the biological responses of Colossoma macropomum after exposure to Malathion. We started determining the lethal concentration, which is the concentration capable of killing 50% of the subjects in an acute toxicity test (LC50-96 h), which was 15.77 ± 3.30 mgL-1. The fish were, then, exposed to Malathion during 96 h at a sublethal concentration, 7.30 mgL-1. Overall, we observed an increased activity of biotransformation and antioxidant enzymes, which reduced production of mitochondrial reactive oxygen species after 96 h exposure, as well as kept constant the mitochondrial respiration, Acetylcholinesterase activity and DNA damage. However, fish exposed to insecticide presented severe gill histopathological damage and increased expression of proto-oncogene ras. Taken together, the results suggest that, after four days of exposure to the Malathion, C. macropomum efficiently activates its defense mechanisms, suggesting that the basal response mechanisms are responsive. On the other hand, histopathologic damages evidenced the adverse effects of Malathion on fish, since it promoted gill necrosis and increased the expression of ras oncogene that is directly related to tumorigenesis events.


Assuntos
Antioxidantes/metabolismo , Caraciformes/metabolismo , Dano ao DNA , Inseticidas/toxicidade , Malation/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Caraciformes/genética , Brânquias/efeitos dos fármacos , Brânquias/patologia , Dose Letal Mediana , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Testes de Toxicidade Aguda
16.
Gene ; 762: 145041, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32777523

RESUMO

Mitochondrial genome sequencing has become widely used in numerous fields, including systematics, phylogeny, and evolutionary genomics. To elucidate phylogenetic relationships among members of the family Characidae, we sequenced the mitogenomes of four species within this family, namely, Aphyocharax rathbuni, Hyphessobrycon herbertaxelrodi, Hyphessobrycon megalopterus, and Prionobrama filigera. The mitogenomes were found to be 16,678-16,841 bp and encode 37 typical mitochondrial genes (13 protein-coding, 2 ribosomal RNA, and 22 transfer RNA genes). Gene arrangements in the studied species are consistent with those in the inferred ancestral fish. Most protein-coding genes in these mitogenomes have typical ATN start codons and TAR or an incomplete stop codon T-. Phylogenetic relationships based on Bayesian inference and maximum-likelihood methods indicated that A. rathbuni, H. herbertaxelrodi, H. megalopterus, and P. filigera belong to the Characidae family. Of the 15 Characidae species studied, three pairs were of the same genus, but the results for only one pair were well supported. This phylogenetic classification is inconsistent with those described in previous morphological and taxonomic studies on this family. Thus, systematic classification of the Characidae requires further examination. Our findings yield new mitogenomic data that will provide a basis for future phylogenetic and taxonomic studies.


Assuntos
Caraciformes/genética , Genoma Mitocondrial , Filogenia , Animais , Caraciformes/classificação , Códon/genética , Anotação de Sequência Molecular , Fases de Leitura Aberta , RNA Ribossômico/genética , RNA de Transferência/genética
17.
Sci Total Environ ; 738: 140339, 2020 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-32806342

RESUMO

Studies have demonstrated the role of acanthocephalan as environmental bioindicators. The dynamics in the parasite-host relationship that define the patterns of distribution of trace metals in parasites and, in its host, are extremely variable. In addition, the neotropical region, which is a major maintainer of the biodiversity of fish and parasites, remains little explored in this subject. Therefore, our objective was to analyze and compare the concentration of Cadmium (Cd) in the tissues of Prochilodus lineatus and Serrasalmus marginatus collected from Baía and Paraná rivers, as well as to assess the use of acanthocephalan as environmental bioindicators of pollution and their Cd bioaccumulation capacity. We collected 53 fish, 20 specimens of Prochilodus lineatus from Paraná River and 17 from Baía River, in addition to 16 specimens of Serrasalmus marginatus from Baía River, in September 2017 and March 2018. Tissues of the fish along with their parasites were subjected a Cd concentration analysis by Atomic Absorption Spectroscopy. The results revealed that the parasites had higher concentrations than all the tissues of S. marginatus, P. lineatus from Baía River and Paraná River. The high Cd concentrations in these parasites derived from their bioaccumulation capacity, because of the absorption of nutrients directly from the intestinal content of the fish through the tegument, as well as for the presence of Cd on the surface waters of Praná River floodplain. Besides that, the Coefficient of Spearman Rank Correlation showed that the infrapopulation size seems to affect Cd bioaccumulation in the parasites, smaller infrapopulations demonstrate a higher accumulation capacity compared to the larger ones. With that, we concluded that the two acanthocephalans species analyzed in this study have a good capacity for Cd accumulation, and can be used as accumulation indicators of trace-metal pollution. Accumulation indicators provide important information on the biological availability of pollutants.


Assuntos
Caraciformes , Parasitos , Animais , Brasil , Cádmio/análise , Biomarcadores Ambientais , Monitoramento Ambiental , Rios
18.
Parasitol Res ; 119(11): 3627-3637, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32852620

RESUMO

This study increases the known biodiversity of cnidarian parasites in neotropical bryconid fishes. Two novel Myxobolus species are described based on morphology, ultrastructure and small subunit ribosomal DNA (ssrDNA) sequencing: Myxobolus vetuschicanus n. sp. infecting fins of Salminus franciscanus and Myxobolus mineirus n. sp. infecting the mesentery of Brycon orthotaenia from the São Francisco River basin, Minas Gerais State, Brazil. Ultrastructural analysis of the two species revealed an asynchronous sporogenesis process, with germinative cells and young developmental stages of myxospores in the periphery of the plasmodia. In M. vetuschicanus n. sp., the plasmodia were surrounded by a layer of fibroblasts and in M. mineirus n. sp., the plasmodial membrane had direct contact with the host tissue. The phylogenetic analysis based on the ssrDNA of Henneguya/Myxobolus species showed that the two novel Myxobolus species grouped in subclades together with other parasite species of bryconid fishes.


Assuntos
Biodiversidade , Caraciformes/parasitologia , Doenças dos Peixes/parasitologia , Myxobolus/isolamento & purificação , Doenças Parasitárias em Animais/parasitologia , Nadadeiras de Animais/parasitologia , Animais , Brasil , DNA Ribossômico , Brânquias/parasitologia , Myxobolus/classificação , Filogenia , Subunidades Ribossômicas Menores de Eucariotos , Rios/parasitologia
19.
Parasitol Res ; 119(10): 3255-3283, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32856113

RESUMO

Seven new species of Urocleidoides from the gills and skin of nine Neotropical fish hosts (Anostomidae, Parodontidae, and Gymnotidae) are described: Urocleidoides digitabulum n. sp. on Leporinus friderici, Leporinus octofasciatus, and Megaleporinus elongatus (Anostomidae); Urocleidoides solarivaginatus n. sp. on L. friderici, L. octofasciatus, and Leporinus striatus (Anostomidae); Urocleidoides falxus n. sp. and Urocleidoides sapucaiensis n. sp. on M. elongatus; Urocleidoides tenuis n. sp. on Apareiodon piracicabae and Apareiodon affinis (Parodontidae); Urocleidoides sinus n. sp. on L. striatus, Schizodon nasutus, and Schizodon intermedius (Anostomidae); and Urocleidoides uncinus n. sp. on Gymnotus sylvius (Gymnotidae). Urocleidoides paradoxus was also found in this study on L. friderici and included in the phylogenetic analysis. Molecular data (partial 28S rDNA and mitochondrial cytochrome oxidase subunit I) were obtained for U. digitabulum n. sp., U. tenuis n. sp., U. sinus n. sp., and U. uncinus n. sp. The identification of Urocleidoides is amended herein to include all taxonomic modifications observed in this genus over time and add new characteristics observed in the species in the present study. Phylogenetic analysis revealed Urocleidoides digitabulum n. sp. and Urocleidoides sinus n. sp. (parasites of anostomids) closely related in the tree topologies. Furthermore, the new species described herein parasitized phylogenetically distant host species (Characiformes and Gymnotiformes), suggesting the effect of the dynamic process of ecological fitting.


Assuntos
Caraciformes/parasitologia , Gimnotiformes/parasitologia , Platelmintos/isolamento & purificação , Animais , Brasil , DNA Mitocondrial/genética , DNA Ribossômico/genética , Peixes , Brânquias/parasitologia , Especificidade de Hospedeiro , Filogenia , Platelmintos/classificação , Platelmintos/genética , RNA Ribossômico 28S/genética
20.
PLoS One ; 15(8): e0237916, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32842138

RESUMO

Highly spread through the Amazon River basin, Prochilodus nigricans have had its taxonomic validity recently questioned, when genetic differences between Western and Eastern Amazon populations from the Brazilian shield were detected. This area has been seeing as a region of high ichthyofaunal diversity and endemism, in which the hybrid origin of the Tapajós River basin has been raised. In this paper, we report a new molecular lineage within P. nigricans of Tapajós River, highlighting this region still hides taxonomically significant diversity. Haplotype networks were reconstructed using the mitochondrial COI and ATP6/8 markers, which were also used to calculate genetic distances among clusters. We additionally conducted a delimiting species approach by employing a Generalized Mixed Yule-Coalescent model (GMYC) with COI sequences produced here, and previous ones published for individuals sampled across the Amazon River basin. In addition to the genetic differentiation within P. nigricans, our findings favor the hypothesis of hybrid origin of the Tapajós River basin and reaffirm the importance of studies aiming to investigate hidden diversity to address taxonomic and biogeographic issues, that certainly benefit better biodiversity conservation actions.


Assuntos
Biodiversidade , Caraciformes/classificação , Caraciformes/genética , Filogenia , Rios , Animais , Teorema de Bayes , Brasil , Geografia , Haplótipos/genética
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