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1.
Braz. j. biol ; 84: e253731, 2024. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1355871

RESUMO

Abstract Petroleum water soluble fraction (WSF) impairs organisms, but damages may vary among cell and tissue levels. The aim of the present study was to evaluate the acute (24 h, 48 h, 72 h) and subchronic effects (36 days) of WSF (0%, 25% and 100%) in juveniles of the Neotropical top predator fish Hoplias aff. malabaricus. The effects of WSF were evaluated at a molecular level using the comet assay and micronucleus test for genome damage; and at a morphological level through histological identification of liver pathologic lesions. In both acute and subchronic exposure we found low levels of DNA damage (< 10% of comet tail) and non-significant frequency of micronucleus in WSF exposed fish. The most significant liver lesions in WSF exposed fish were fatty vacuolization, hypertrophy and focal necrosis. Since these tissue injuries were progressive and persistent, their irreversibility may negatively affect fish recruitment, even in a such resistant top predator.


Resumo A fração solúvel de petróleo (WSF) prejudica os organismos, porém os danos podem variar entre os níveis celular e tecidual. O objetivo do presente estudo foi avaliar o efeito agudo (24 h, 48 h e 72 h) e subcrônico (36 dias) da WSF (0%, 25% e 100%) em juvenis do peixe neotropical predador topo Hoplias aff. malabaricus. Os efeitos da WSF foram avaliados no nível molecular utilizando o ensaio do cometa e o teste do micronúcleo para o dano genômico e no nível morfológico através da identificação histológica de lesões patológicas no fígado. Em ambas exposições (aguda e subcrônica) encontramos baixos níveis de dano no DNA (< 10% de DNA na cauda do cometa) e frequência de micronúcleos não significativa em peixes expostos a WSF. As lesões mais significativas no fígado dos peixes expostos a WSF foram a vacuolização lipídica, hipertrofia e focos de necroses. Como estas lesões foram progressivas e persistentes, sua irreversibilidade pode afetar negativamente o recrutamento dos peixes, mesmo sendo um predador topo resistente.


Assuntos
Animais , Poluentes Químicos da Água/toxicidade , Petróleo/toxicidade , Caraciformes , Água Doce , Fígado
2.
Braz. j. biol ; 84: e253852, 2024. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1355905

RESUMO

Abstract The aim objective of this study was to determine the trophic ecology of juvenile and adult Acestrorhynchus falcirostris during the rising and flood (high-water) period in six island lakes adjacent to the Solimões River. As such, we investigated: i) the trophic position, through the fractional trophic niche; ii) the niche breadth; iii) niche overlap and iv) the food strategy of the species. The specimens were collected during the years 2014 to 2017, using gillnets with mesh sizes ranging from 30 to 120mm between opposite knots. Through the analysis of stomach contents, the preference in the consumption of items of animal origin was observed. Juveniles consumed insects in greater proportions (IAi% = 50%), while adults consumed fish (IAi%=99,98%). Despite the large supply of food items available in the high-water period, juveniles were the only ones to consume items of allochthonous origin, such as insects. Juveniles presented a different dietary strategy and dietary composition to adults. Juveniles were omnivores with a generalist strategy, while adults were piscivores with a specialist strategy. Thus, the food composition, niche breadth, trophic position and feeding strategy of Acestrorhynchus falcirostris change due to the stage of development.


Resumo O objetivo deste estudo foi determinar a ecologia trófica de juvenis e adultos de Acestrorhynchus falcirostris durante o período de enchente e cheia em seis lagos de ilha adjacentes ao rio Solimões. Assim, investigamos: i) a posição trófica, através do nicho trófico fracional; ii) a largura de nicho; iii) sobreposição de nicho; iv) a estratégia alimentar. Os espécimes foram coletados durante os anos de 2014 a 2017, utilizando redes de emalhar com malha variando de 30 a 120mm entre nós opostos. Por meio da análise do conteúdo estomacal, observamos a preferência no consumo de itens de origem animal. Os juvenis consumiram insetos em maiores proporções (IAi% = 50%), enquanto os adultos consumiram preferencialmente peixes (IAi% = 99,98%). Apesar da grande oferta de alimentos disponíveis no período da cheia, os juvenis eram os únicos a consumir itens de origem alóctone, como por exemplo, os insetos. Os juvenis apresentaram uma estratégia alimentar e composição alimentar diferente para os adultos. Os juvenis foram considerados onívoros com uma estratégia generalista, enquanto os adultos foram considerados piscívoros com uma estratégia alimentar mais especialista. Assim, a composição alimentar, amplitude do nicho, posição trófica e a estratégia alimentar de Acestrorhynchus falcirostris muda em função do estágio de desenvolvimento.


Assuntos
Animais , Rios , Caraciformes , Estações do Ano , Lagos , Ecossistema , Cadeia Alimentar , Peixes , Conteúdo Gastrointestinal
3.
Braz. j. biol ; 83: e250003, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1339392

RESUMO

Abstract This study estimated the length-weight relationships of 16 fish species occurring close to the shores of sandy beaches along the lower Negro River basin, Brazilian Amazon. The specimens were captured for one day each month, in October to November 2016, early in the morning and early evening, using trawl net (20 m taken for standard length (SL - 0.1 cm precision) and total weight (TW - 0.01 g precision). The parameters a and b of the equation WT = a.LTb were estimated. The a values ranged from 0.0018 to 0.0226 and b values ranged from 2.5271 to 3.3244. This study also provides new data on of maximum lengths for six species, Amazonsprattus scintilla, Brycon pesu, Moenkhausia megalops, Pachyurus paucirastrus, Reganella depressa and Trachydoras microstomus, and new reports of the LWRs parameters of 15 fish species.


Resumo Este estudo estimou as relações comprimento-peso de 16 espécies de peixes que ocorrem às margens de praias arenosas ao longo da bacia do baixo Rio Negro, Amazônia brasileira. As espécies foram capturadas durante um dia de cada mês, de outubro a novembro de 2016, no início da manhã e no início da noite, usando rede de cerco (20 m de comprimento e 3,5 m de altura, 5 malha mm entre nós opostos). As medidas foram feitas para comprimento padrão (SL - precisão de 0,1 cm) e peso total (TW - precisão de 0,01 g). Os parâmetros a e b da equação WT = a.LTb foram estimados. Os valores de a variaram de 0,0018 a 0,0226 e os valores de b variaram de 2,5271 a 3,3244. Este estudo também fornece novos dados sobre comprimentos máximos para seis espécies, Amazonsprattus scintilla, Brycon pesu, Moenkhausia megalops, Pachyurus paucirastrus, Reganella depressa e Trachydoras microstomus, e novos reportes dos parâmetros da LWRs de 15 espécies de peixes.


Assuntos
Animais , Perciformes , Caraciformes , Characidae , Brasil , Rios
4.
Braz. j. biol ; 83: e244784, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1278541

RESUMO

Abstract The work aimed to evaluate the weight-length relationship and the condition factor, characterizing the biometry, anatomy, histology and volumetric density of the liver of Brycon amazonicus, in different stages of body growth. The experiment used twenty specimens in four stages of body growth (PI, PII, PIII and PIV) harvested every 90 days, containing five specimens, each group. The livers were dissected, weighed (g) and processed routinely using the hematoxylin and eosin technique. The data were submitted to analysis of variance, Pearson's correlation test and linear regression. The equation that represented the weight-length relation was W = 0.05902 x L2.63, with negative allometric growth, but with a relative condition factor equal to 1.0. The liver was divided into three lobes with the gallbladder close to the right lobe and its color varied from light red to dark red, not varying in relation to other fish species. The hepatosomatic relationship followed body growth until the PII group stage and then declined, demonstrating the behavior of its development in Brycon amazonicus. The organ consists predominantly of hepatocytes, followed by sinusoidal vessels and capillaries, with histological morphology similar to that of many species of fish. Melanomacrophage centers were found only in the most developed animals, but in small quantities, prompting the development of new research on this cell, in this species. In this way, research of this nature allows the characterization of fish species, helping to improve breeding methods, understanding pathological processes caused by diseases, and obtaining better productive capacity, serving an increasingly demanding and prosperous market.


Resumo O trabalho objetivou avaliar a relação peso-comprimento e o fator de condição, caracterizando a biometria, anatomia, histologia e densidade volumétrica do fígado de Brycon amazonicus, em diferentes estágios de crescimento corporal. O experimento utilizou vinte espécimes em quatro fases de crescimento corporal (PI, PII, PIII e PIV) colhidos a cada 90 dias, contendo cinco espécimes, cada grupo. Os fígados foram dissecados, pesados (g) e processados rotineiramente pela técnica da hematoxilina e eosina. Os dados foram submetidos à análise de variância, teste de correlação de Pearson e regressão linear. A equação que representou a relação peso-comprimento foi W = 0,05902 x L2,63, com crescimento alométrico negativo, mas com fator de condição relativo igual a 1,0. O fígado apresentou-se dividido em três lobos com a vesícula biliar próxima ao lobo direito e sua cor variou de vermelho claro a vermelho escuro, não variando em relação a outras espécies de peixes. A relação hepatossomática acompanhou o crescimento corporal até a fase do grupo PII e então declinou, demonstrando o comportamento de seu desenvolvimento em Brycon amazonicus. O órgão constitui-se predominantemente por hepatócitos, seguido de vasos e capilares sinusoidais, com a morfologia histológica semelhante ao de muitas espécies de peixes. Centros melanomacrófagos foram encontrados apenas nos animais mais desenvolvidos, mas em pequena quantidade, instigando o desenvolvimento de novas pesquisas sobre esta célula, nesta espécie. Desta forma, pesquisas desta natureza permitem a caracterização de espécies de peixes, auxiliando no aperfeiçoamento de métodos de criação, compreensão de processos patológicos provocados por enfermidades, e obtenção de melhor capacidade produtiva, atendendo um mercado cada vez mais exigente e próspero.


Assuntos
Animais , Caraciformes , Fígado
6.
An Acad Bras Cienc ; 94(3): e20201687, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36074402

RESUMO

Prochilodus lineatus has been considered an ecosystem engineer in the Neotropics given its influence on important ecosystem processes, and it is therefore relevant to understand their inter-specific relationships. The association of P. lineatus with parasitic helminths was studied in two isolated shallow lakes of the alluvial plain of the Middle Paraná River. Only two species of gastrointestinal nematodes were found: Spinitectus asperus (Cystidicolidae) and Klossinemella iheringi (Atractidae), with S. asperus having higher prevalence and mean intensity values. This is the first record of K. iheringi in the Middle Paraná River, Argentina, as well as the southernmost citation of S. asperus.


Assuntos
Caraciformes , Nematoides , Animais , Argentina , Ecossistema , Peixes/parasitologia , Rios
7.
Gene ; 843: 146795, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-35961435

RESUMO

The genes coding for Cytochrome P450 aromatase (cyp19a1a and cyp19a1b) and estrogen (E2) receptors (esr1, esr2a and esr2b) play a conserved role in ovarian differentiation and development among teleosts. Classically, the "gonad form" of aromatase, coded by the cyp19a1a, is responsible for the ovarian differentiation in genetic females via ligation and activation of the Esr, which mediates the endocrine and exocrine signaling to allow or block the establishment of the feminine phenotype. However, in neotropical species, studies on the molecular and endocrine processes involved in gonad differentiation as well as on the effects of sex modulators are recent and scarce. In this study, we combined in silico analysis, real-time quantitative PCR (qPCR) assay and quantification of E2 plasma levels of differentiating tambaqui (Colossoma macropomum) to unveil the roles of the paralogs cypa19a1a and cyp19a1b during sex differentiation. Although the synteny of each gene is very conserved among characids, the genomic environment displays striking differences in comparison to model teleost species, with many rearrangements in cyp19a1a and cyp19a1b adjacencies and transposable element traces in both regulatory regions. The high dissimilarity (DI) of SF-1 binding motifs in cyp19a1a (DI = 10.06 to 14.90 %) and cyp19a1b (DI = 8.41 to 13.50 %) regulatory region, respectively, may reflect in an alternative pathway in tambaqui. Indeed, while low transcription of cyp19a1a was detected prior to sex differentiation, the expression of cyp19a1b and esr2a presented a large variation at this phase, which could be associated with sex-specific differential expression. Histological analysis revealed that anti-estradiol treatments did not affect gonadal sex ratios, although Fadrozole (50 mg kg-1 of food) reduced E2 plasma levels (p < 0,005) as well cyp19a1a transcription; and tamoxifen (200 mg kg-1 of food) down regulated both cyp19a1a and cyp19a1b but did not influence E2 levels. Altogether, our results bring into light new insights about the evolutionary fate of cyp19a1 paralogs in neotropical fish, which may have generated uncommon roles for the gonadal and brain forms of cyp19a1 genes and the unexpected lack of effect of endocrine disruptors on tambaqui sexual differentiation.


Assuntos
Aromatase , Caraciformes , Animais , Aromatase/genética , Aromatase/metabolismo , Caraciformes/genética , Feminino , Gônadas/metabolismo , Masculino , Filogenia , Diferenciação Sexual/genética
8.
Theriogenology ; 191: 22-34, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35939901

RESUMO

A preservation protocol has not been established for Colossoma macropomum oocytes, and its development may improve the production and breeding programs of this South American fish species. Thus, this study aimed to determine the effect of different methods and protocols for the preservation of C. macropomum oocytes. Seven experiments were conducted throughout the breeding season of this species. The oocytes were collected and stored in sterile conditions. Preserved oocytes were subjected to storage in the following treatments: room temperature (RT, 27 °C), centrifugation followed by ovarian fluid removal (Cen), vacuum (Vac), chilled temperature (ChT), centrifugation and vacuum (CV), vacuum and chilled temperature (VChT), and centrifugation, vacuum, and chilled temperature (CVChT) in dry sterilized plastic containers and plastic bags. Chilled storage was tested at 4 and 13 °C. Fertilization and hatching rates were assessed at 0, 30, 60, 90, and 120 min after stripping (MAS) for preservation protocols. The larval malformation rate was analyzed at 0 and 30 MAS for RT and ChT. Quantitation and identification (by mean of MALDI-TOF MS) of bacteria were performed at 0, 60, 90, and 120 MAS, and scanning electron microscopy (SEM) analyses were carried out at 0, 60, and 90 MAS. The fertilization and hatching rates decreased over preservation time and breeding season. RT samples fertilized at 0, 30, and 60 MAS yielded similar fertilization rates at both the beginning and end of the season. By the end of the season, oocytes from treatment ChT at 13 °C 30 MAS yielded higher fertilization and hatching rates, and a lower percentage of larvae malformation than RT 30 MAS. The treatment ChT at 4 °C triggered low a fertilization rate. The treatments ChT (13 °C) and Cen provided good fertilization rate when used alone and with other approaches, i.e., treatments VChT, CV, and CVChT. The treatment Vac presented inconsistent results, so no conclusion could be made. Bacterial colony counts were low (10-1.6 × 105 CFU-mL-1), and a total of 18 bacteria species were identified in all batches analyzed; however, the treatments did not influence the number of bacteria. C. macropomum female breeders presented distinct bacteria species in their oocytes and the presence of bacteria did not impair oocyte quality until 120 MAS. Moreover, SEM analyses showed that the micropyle was not occluded during oocyte storage, and ovarian fluid was observed on the surface of chilled oocytes. Therefore, Colossoma macropomum oocytes could be preserved under chilled storage at 13 °C for 30 min throughout its breeding season.


Assuntos
Caraciformes , Oócitos , Animais , Feminino , Fertilização , Plásticos , Temperatura
9.
J Helminthol ; 96: e61, 2022 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-35979699

RESUMO

In Argentina, the family Diplostomidae is composed of eight genera: Austrodiplostomum Szidat & Nani; Diplostomum von Nordmann; Dolichorchis Dubois; Hysteromorpha Lutz; Neodiplostomum Railliet; Posthodiplostomum Dubois; Sphincterodiplostomum Dubois; and Tylodelphys Diesing. During a parasitological survey of fishes from the Iguazú National Park we detected diplostomid metacercariae in the brain of Erythrinus cf. erythrinus. Fish were caught using crab traps, transported alive to the field laboratory, cold-anaesthetized and euthanized by cervical dissection. Some metacercariae were heat-killed in water and fixed in 10% formalin and others were preserved in alcohol 96% for DNA extraction. They were sequenced for the partial segment of the 28S rDNA, internal transcribed spacer (ITS) rDNA and cytochrome c oxidase subunit I (COI) mtDNA genes. Phylogenetic reconstruction was carried out using Bayesian inference and the proportion (p) of absolute nucleotide sites (p-distance) was obtained. In the 28S rDNA tree, the metacercaria sequenced grouped as Dolichorchis sp. The COI mtDNA p-distance between the metacercariae with Dolichorchis lacombeensis was 0.01. There is a small number of ITS sequences for the Diplostomidae family deposited in the GenBank. The oral sucker, ventral sucker, holdfast organ and the distance between oral and ventral suckers are larger in the adult compared with the metacercariae. Additionally, hind-body length and width are larger in the adult due to the development of the genital complex. Further studies using an integrative approach will help confirm the affiliation of other species to the genus Dolichorchis.


Assuntos
Caraciformes , Doenças dos Peixes , Trematódeos , Infecções por Trematódeos , Animais , Argentina , Teorema de Bayes , Encéfalo , DNA Mitocondrial/genética , DNA Ribossômico/genética , Metacercárias/genética , Parques Recreativos , Filogenia , Infecções por Trematódeos/veterinária
10.
Rev Bras Parasitol Vet ; 31(3): e005722, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36000679

RESUMO

This paper investigated information on monogenean species using 312 scientific papers, to search for infection and geographic distribution patterns in native freshwater fish from Brazil. We used 1,698 samples of 296 fish species of 28 families distributed into Characiformes, Siluriformes, Cichliformes, Gymnotiformes, Perciformes, Mugiliformes, Osteoglossiformes and Clupeiformes, in addition to four hybrid fish. Among the hosts of the different orders and families, the greatest numbers of parasite-host associations were found for species of the families Serrasalmidae, Characidae, Loricariidae, Curimatidae and Anostomidae. The 578 species of monogeneans used in parasite-host interactions were distributed in 86 genera of six five families (Dactylogyridae, Gyrodactylidae, Diplectanidae, Microcotylidae, Ancylodiscoididae and Ancyrocephalidae), but with great predominance of Dactylogyridae species. There was variation in prevalence, intensity and abundance levels of monogeneans species among host fish species, as well as in infection sites that occurred predominantly in external organs. Positive correlations of prevalence, intensity and abundance with body length of hosts were observed. There was geographic distribution pattern of monogeneans limited mostly to two hydrographic basins those being the Amazon River and Paraná River. Just approximately 6% of potential monogeneans have been explored thus far, showing a clear need for further studies on this interesting group of parasites.


Assuntos
Peixes-Gato , Caraciformes , Doenças dos Peixes , Trematódeos , Animais , Brasil , Caraciformes/parasitologia , Doenças dos Peixes/parasitologia , Peixes/parasitologia , Água Doce , Interações Hospedeiro-Parasita
11.
An Acad Bras Cienc ; 94(4): e20210258, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35830072

RESUMO

Tambaqui is the second native fish most produced species in Brazil. Currently, tambaqui fish farms deals with serious sanitary problems due to the prevalence of the parasite Neoechinorhynchus buttnerae. However, the prevalence of the acanthocephalan parasite infections depends on the resistance and tolerance interactions between the host organisms and parasites. The immune response against parasites is divided between innate and acquired immunity. The innate defense is a result of physical barriers, cellular and humoral compounds. Acquired defense occurs through the production of antibodies (humoral) and is mediated by cells, mainly by type 2 T helper lymphocytes. Most parasites secrete a variety of immunomodulatory compounds that allow coexistence with the host and chronicity of the parasite. The host-parasite relationship is complex and makes prevention and treatment difficult. However, some studies show that the use of immunostimulants may have "systemic" effects. These include improvement of the intestinal mucosa health and also in the production of cellular and humoral compounds in the whole body, thus assisting treatment and control. As such, it is important to understand the mechanisms of resistance and tolerance in the host organisms so that prevention and treatment measures can be effective.


Assuntos
Acantocéfalos , Caraciformes , Doenças dos Peixes , Parasitos , Animais , Aquicultura , Caraciformes/parasitologia , Doenças dos Peixes/parasitologia
12.
Rev Bras Parasitol Vet ; 31(3): e005122, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35894419

RESUMO

During a survey of the helminth fauna of characiform fishes from the Tocantins River, Brazil, 185 fish specimens from 22 species were studied. Twelve species of Nematoda and nine species of Digenea were collected. Some of these helminth species were reported for the first time in their hosts, thus representing new host records: Procamallanus (Spirocamallanus) sp. in Bivibranchia notata, Brycon pesu, Chalceus macrolepidotus, Hemiodus microlepis and Hemiodus unimaculatus; Procamallanus (Spirocamallanus) inopinatus in Triportheus elongatus; Goezia sp. (larva) in Boulengerella cuvieri; Rhabdochona acuminata in Brycon pesu and Triportheus trifurcatus; Raphidascaris sp. (larva) in Caenotropus labyrinthicus; Cosmoxynema vianai in Cyphocharax gouldingi; Rondonia rondoni in Leporinus fasciatus and Mylesinus paucisquamatus; Klossinemella iheringi in Mylesinus paucisquamatus; Cucullanidae gen. sp. in Myloplus rubripinnis; Rhabdochona sp. in Triportheus elongatus; Alphamphistoma sp. in Myleus setiger; Chalcinotrema sp. in Cyphocharax gouldingi; Pacudistoma guianense in Hemiodus unimaculatus and Myleus torquatus; Pseudocladorchis cylindricus in Hemiodus unimaculatus; Dadaytrema oxycephala in Mylesinus paucisquamatus; Travassosinia dilatata in Myloplus asterias; and Genarchella genarchella in Raphiodon vulpinus. Studies identifying new hosts and new localities for parasites have contributed to the knowledge of local biodiversity. A list of previous records of helminths included in the present study, providing hosts, localities, and references, is presented here.


Assuntos
Ascaridoidea , Caraciformes , Doenças dos Peixes , Helmintos , Nematoides , Espirurídios , Trematódeos , Animais , Brasil , Caraciformes/parasitologia , Doenças dos Peixes/parasitologia , Peixes/parasitologia , Rios
13.
Mol Ecol ; 31(18): 4656-4671, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35729748

RESUMO

Associations between host genotype and host-associated microbiomes have been shown in a variety of animal clades, but studies on teleosts mostly show weak associations. Our study aimed to explore these relationships in four sympatric Serrasalmidae (i.e., piranha) teleosts from an Amazonian lake, using data sets from the hosts genomes (single nucleotide polymorphisms from genotyping by sequencing), skin and gut microbiomes (16S rRNA gene metataxonomics) and diets (COI metabarcoding) from the same fish individuals. First, we investigated whether there were significant covariations of microbiome and fish genotypes at the inter- and intraspecific levels. We also assessed the extent of covariation between Serrasalmidae diet and microbiome, to isolate genotypic from dietary effects on community structure. We observed a significant covariation of skin microbiomes and host genotypes at interspecific (R2  = 24.4%) and intraspecific (R2  = 6.2%) levels, whereas gut microbiomes correlated poorly with host genotypes. Serrasalmidae diet composition was significantly correlated to fish genotype only at the interspecific level (R2  = 5.4%), but did not covary with gut microbiome composition (Mantel R = -.04). Second, we investigated whether the study of interspecific differentiation could benefit from considering host-associated microbial communities in addition to host genotypes. By using a nonmetric multidimensional scaling (NMDS) ordination-based approach, we observed that ordinations from skin- and gut species-specific bacterial biomarkers identified through a random forest algorithm could significantly increase the average interspecific differentiation detected through host genotype data alone. Although future studies encompassing additional species and environments are needed, our results suggest Serrasalmidae microbiomes could constitute an insightful trait to be considered when studying the interspecific differences between members of this clade.


Assuntos
Caraciformes , Microbioma Gastrointestinal , Microbiota , Animais , Caraciformes/genética , Microbioma Gastrointestinal/genética , Genômica , Microbiota/genética , RNA Ribossômico 16S/genética
14.
Rev Bras Parasitol Vet ; 31(2): e006822, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35674534

RESUMO

This study was carried out to evaluate the anthelminthic efficacy of seeds of Cucurbita maxima and Carica papaya for controlling monogeneans in the gills of Leporinus macrocephalus, besides hepatosomatic and splenosomatic index and condition factor of host. The fish were fed with seeds of C. maxima or C. papaya for seven days, and these treatments did not cause any mortality among them. Jainus leporini, Urocleidoides paradoxus, Urocleidoides eremitus and Tereancistrum parvus were the monogeneans found, and their prevalence in fish fed with seeds of C. papaya was 100%, while in fish fed with C. maxima the prevalence was 42.8%. Fish fed with seeds of C. papaya showed decreased in intensity and abundance of monogeneans, while fish fed with seeds of C. maxima presented decreased in abundance. Feeding of L. macrocephalus with seeds of C. maxima or C. papaya had efficacy of 69.6 and 67.8%, respectively. The hepatosomatic index of fish fed with seeds of C. maxima or C. papaya was not affected by the treatments. However, the splenosomatic index and condition factor of fish fed with C. maxima seeds decreased. Seeds of C. maxima and C. papaya may be used for controlling monogeneans of L. macrocephalus in fish farming.


Assuntos
Carica , Caraciformes , Cucurbita , Trematódeos , Animais , Brânquias , Extratos Vegetais , Sementes
15.
Parasitol Res ; 121(8): 2295-2305, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35705719

RESUMO

The aim of this study was to investigate the microhabitat affinities of Ergasilus sp. and Therodamas longicollum on the gills of Leporinus fasciatus ("aracu-piau"), an anostomid fish from the Amazon. A total of 143 specimens of L. fasciatus were examined, of which 35% had their gills parasitized by at least one ergasilid species. A total of 159 specimens of Ergasilus sp. and 97 specimens of T. longicollum were recovered. Both ergasilids species exhibited a greater affinity for attachment in arch 1 of the gills of the host. There was a negative correlation between the abundance of Ergasilus sp. and the abundance of T. longicollum within each gill arch. Analysis of distribution along the gill arch showed a higher occurrence of Ergasilus sp. in Section 5, while T. longicollum occurred mainly in Section 3 of the gills. There was a positive correlation between the abundance of these ectoparasites and the size of the gill arch. Ergasilus sp. occurred only on the filament of the gill arch and exhibited affinity for the proximal region, while T. longicollum occurred only in the gill arch itself. The results reveal that these two parasite species compete in the gills of the host without the overlapping of their niches.


Assuntos
Acantocéfalos , Caraciformes , Copépodes , Doenças dos Peixes , Parasitos , Animais , Brasil , Copépodes/anatomia & histologia , Doenças dos Peixes/parasitologia , Brânquias/parasitologia
16.
Acta Parasitol ; 67(3): 1432-1439, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35639231

RESUMO

PURPOSE: The present study aims to report the occurrence of Eustrongylides sp. in some neotropical fish species commercialized in the Peruvian Amazonia. METHODS: Samples of young farmed Arapaima gigas were collected from a fish farmer; young Brachyplatystoma tigrinum were acquired from a fish exporter and samples of adult specimens of Acestrorhynchus falcirostris, Pseudoplatystoma punctifer, Cichla monoculus, Hoplias malabaricus, Hydrolycus scomberoides, Raphiodon vulpinus, and Serrasalmus rhombeus were acquired from a fish market of Iquitos, Loreto-Peru. Samples were transported to the "Laboratorio de Parasiología y Sanidad Acuícola" from "Instituto de Investigaciones de la Amazonía Peruana" located in Iquitos, Peru. RESULTS: Larvae L4 of Eustrongylides sp. were found in the host body, in the muscle, and in the visceral cavity of studied fish species. Notorious damages were reported in young A. gigas (lumps in the muscle, inflammation and severe redness of the skin) and in young B. tigrinum (perforation of the abdominal cavity), while in adult specimens of the remaining species, no external damage was reported. CONCLUSION: The presence of Eustrongylides sp. in various fish species collected in the city of Iquitos-Peru contributes to the distribution of this parasite in the Peruvian Amazon, reporting it, for the first time in this country. Its presence in the muscle of various fish species commercialized in fish markets, warm a possible public health concern and implications for their marketability in the city of Iquitos, Peru.


Assuntos
Peixes-Gato , Caraciformes , Doenças dos Peixes , Nematoides , Animais , Caraciformes/parasitologia , Doenças dos Peixes/epidemiologia , Doenças dos Peixes/parasitologia , Peru/epidemiologia , Saúde Pública
17.
An Acad Bras Cienc ; 94(2): e20190919, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35384963

RESUMO

The gametogenesis and reproduction of S. elegans from the São Francisco River at Três Marias, Minas Gerais, were analyzed in this study. Steindachrina elegans is a species abundant in the São Francisco River basin and an important fish in the food chain. The size at first gonadal maturation (indicated by the total length of the shortest spermatid male and spawned female) was 10.5 cm and 15.0 cm, respectively. Reproduction occurred more frequently from September to April. This period had high water temperature values. A high frequency of females was observed at the mature and spawned stages and height gonadosomatic index (GSI). Meanwhile, in males, the reproductive peak was from November to February. The long spawning period and the histological characteristics of the spawned ovaries that contained oocytes at different stages of development along with post-ovulatory and atretic oocytes indicates that the spawning of S. elegans is of the partial type.


Assuntos
Caraciformes , Reprodução , Animais , Brasil , Feminino , Gônadas , Masculino , Rios , Estações do Ano
18.
Rev Bras Parasitol Vet ; 31(2): e000422, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35476007

RESUMO

The endoparasitic fauna of Acestrorhynchus lacustris from eight marginal lagoons of the upper and middle São Francisco river basin, Brazil, is recorded here for the first time. For this, a total of 106 specimens of A. lacustris were collected. Eighteen helminth species were found. The taxa recorded were phylum Platyhelminthes: one metacercaria of Clinostomum sp. (Trematoda: Clinostomidae) and plerocercoid larvae of unidentified species (Eucestoda: Proteocephalidae gen. sp.); phylum Acanthocephala: juvenile of Quadrigyrus sp.; and phylum Nematoda: larvae of Brevimulticaecum sp., Contracaecum sp. Type1, Contracaecum sp. Type2, Hysterothylacium sp., Gnathostoma sp., Spiroxys sp., juvenile and adult specimens of Freitascapillaria sp., Paracapillaria piscicola, Capillariidae gen. sp., Procamallanus (Spirocamallanus) hilarii, Procamallanus (S.) inopinatus, Procamallanus (S.) saofranciscencis, Travassosnema travassosi paranaensis, Cystidicoloides fischeri and Spinitectus rodolphiheringi. Proteocephalidae gen. sp., Contracaecum sp. Type1 and Travassosnema t. paranaensis were present in all eight lagoons with high parasitic indexes. Proteocephalidae gen. sp., Brevimulticaecum sp., Gnathostoma sp., Freitascapillaria sp., P. piscicola, Capillariidae gen. sp., Procamallanus (S.) hilarii, C. fischeri and S. rodolphiheringi are new records for A. lacustris. The known geographical distribution of Gnathostoma sp., Freitascapillaria sp., P. piscicola, Capillariidae gen. sp., Procamallanus (S.) hilarii and Travassosnema t. paranaensis has now been extended to the São Francisco river basin.


Assuntos
Ascaridoidea , Caraciformes , Helmintos , Sanguessugas , Espirurídios , Animais , Brasil , Caraciformes/parasitologia , Rios
19.
Rev Bras Parasitol Vet ; 31(2): e000922, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35476008

RESUMO

Our aim was to assess endoparasite diversity and liver alterations in Hoplerythrinus unitaeniatus (jeju) and Cichlasoma bimaculatum (acará preto) in a quilombola area in Maranhão, Brazil. For this, 21 H. unitaeniatus and 21 C. bimaculatum were caught in a natural environment and transported to a laboratory. After these had been euthanized, endoparasites were collected and identified. Liver alterations were evaluated histological analysis based on the severity of each lesion: stage I, organ functioning not compromised; stage II, more severe lesions that impair normal functioning of the organs; and stage III, very severe and irreversible lesions. Among the fish evaluated, 71.43% H. unitaeniatus and 61.90% C. bimaculatum were parasitized. Contracaecum sp. was found in both species; while acanthocephalans, only in H. unitaeniatus. The alterations were vacuolization, nucleus in the cell periphery, deformation of the cell outline, melanomacrophage center, hyperemia, cytoplasmic degeneration and nuclear vacuolization. Through calculating a histological alteration index, it was found that 26.19% of the specimens presented lesions in stage I; 38.09% lesions in stage II and 9.52% lesions in stage III. It was concluded that there is high prevalence of Contracaecum sp. and that the liver lesions may be adaptive responses by the fish to endoparasitic infection.


Assuntos
Acantocéfalos , Caraciformes/parasitologia , Ciclídeos/parasitologia , Doenças dos Peixes/parasitologia , Helmintíase Animal/patologia , Fígado/patologia , Animais , Brasil , Doenças dos Peixes/patologia , Helmintíase Animal/parasitologia , Fígado/parasitologia
20.
Environ Toxicol Pharmacol ; 92: 103862, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35405334

RESUMO

We aimed to evaluate if Lemna minor can mitigate the observed effects of cadmium (Cd) and nickel (Ni) exposure in Prochilodus lineatus. Fish were exposed for 96 h to 20 µg L-1 of Cd, 1.5 mg L-1 of Ni, or to a mixture of these two metals. In all tests, one group was exposed to the metals with duckweed on the water surface, and other group was exposed only to the metals, without plants. After each exposure, samples of P. lineatus tissues were collected to evaluate multiple biomarkers. Duckweed prevented bioaccumulation in some fish tissues and attenuated changes in acetylcholinesterase activity, increases in erythrocytic nuclear abnormality frequency, and hyperglycemia. However, the changes in plasma ion concentrations, reduction in activity of ion transport enzymes, and histological damage were not mitigated. Therefore, we concluded that L. minor partially attenuates the effects caused by Cd and Ni exposure.


Assuntos
Araceae , Caraciformes , Poluentes Químicos da Água , Acetilcolinesterase , Animais , Cádmio/toxicidade , Níquel/toxicidade , Poluentes Químicos da Água/toxicidade
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