RESUMO
The present study describes Udonella brasiliensis n. sp., an epibiont found on Caligus sp., a parasite the ariids Genidens barbus (Lacepède) and Aspistor luniscutis (Valenciennes), caught on the coast of the state of São Paulo, Brazil. Morphological and molecular analyses (partial 18S rDNA) were carried out. The morphological data showed that U. brasiliensis n. sp. can be distinguished from current valid species by its morphometric attributes (e.g., body, pharynx, ovary and testis), while the molecular information supports the proposal of a new species. The 18S rDNA phylogenetic analysis shows a close relationship between the new species and Udonella australis Carvajal & Sepulveda, in a subclade formed of species that parasitize South American fish. Finally, this study also discusses a scenario of initial irradiation for udonellids.
Assuntos
Peixes-Gato , Copépodes/parasitologia , Doenças dos Peixes/epidemiologia , Simbiose , Trematódeos/anatomia & histologia , Trematódeos/genética , Infecções por Trematódeos/veterinária , Animais , Brasil/epidemiologia , Doenças dos Peixes/parasitologia , Filogenia , RNA de Helmintos/análise , RNA Ribossômico 18S/análise , Infecções por Trematódeos/epidemiologia , Infecções por Trematódeos/parasitologiaRESUMO
A total of 122 Patinga specimens were collected from fish farms (P1, P2 and P3), and only those from fish farm P1 were shown to be infected with Echinorhynchus gomesi. In addition, fish in this study were shown to have diets that consisted of 21 different food items, and Notodiaptomus sp. (Copepoda: Calanoida) was identified as a potential intermediate host for E. gomesi.
Assuntos
Acantocéfalos/fisiologia , Caraciformes/parasitologia , Doenças dos Peixes/parasitologia , Cadeia Alimentar , Helmintíase Animal/parasitologia , Animais , Copépodes/parasitologia , Doenças dos Peixes/transmissão , Pesqueiros , Helmintíase Animal/transmissãoRESUMO
Trichodinid ciliates were isolated from calanoid copepods and were characterized by morphological and molecular techniques. The trichodinids found in this study were morphologically similar to Trichodina acuta, but morphometric differences were observed between our specimens and T. acuta. The T. acuta specimens, isolated from fish in several geographical locations around the world, were slightly larger than specimens in our population. In fact, our morphological and morphometric data are more similar to Trichodina diaptomi populations, also found on copepods. Moreover, our phylogenetic analyses revealed that the 18S rRNA gene sequence from our samples emerged in a clade with two T. acuta sequences, infesting fish hosts in China. These three sequences showed 100% identity. Our data, along with a taxonomic review, suggest that the species T. diaptomi, described recently, is actually a synonym of T. acuta and that this species may be related to fish and copepod hosts. In conclusion, we highlight the urgent need to better investigate the polymorphism and host specificity within the Mobilida, as this data may represent important characters to better understand the evolution into this order.
Assuntos
Copépodes/parasitologia , Oligoimenóforos/classificação , Animais , DNA de Protozoário/genética , Peixes/parasitologia , Especificidade de Hospedeiro , Oligoimenóforos/citologia , Oligoimenóforos/genética , Filogenia , RNA Ribossômico 18S/genética , Análise de Sequência de DNARESUMO
Sea lice are widespread copepods in marine teleost around the world. In this paper the first record of Caligus asperimanus Pearse, 1951 in the Western South Atlantic is documented parasitizing Lutjanus jocu and Lutjanus vivanus caught from coastal zones of Espírito Santo and Rio de Janeiro State, respectively.(AU)
Os piolhos marinhos são copépodes abrangentemente relatados em teleósteos marinhos ao redor do mundo. Neste estudo, é documentado o primeiro registro de Caligus asperimanus Pearse, 1951, no Atlântico Sul Ocidental, parasitando Lutjanus jocu e Lutjanus vivanus capturados nas zonas costeiras do Espírito Santo e Rio de Janeiro, respectivamente.(AU)
Assuntos
Animais , Perciformes/classificação , Perciformes/parasitologia , Copépodes/parasitologiaRESUMO
São constantes os relatos de parasitos de peixes de cultivo no estado de Rondônia, Brasil. Os crustáceos são importantes parasitos que ocasionam prejuízos aos peixes cultivados. Possuem uma grande diversidade de espécies e chamam a atenção por serem macroscópicos na fase parasitária e apresentarem ampla variação de forma e tamanho. Dessa forma, o presente estudo objetiva relatar a identificação de Perulernaea gamitanae (Crustacea: Lernaeidae) pela primeira vez em peixes pirapitinga (Piaractus brachypomus). Foram coletados lerneídeos parasitos na língua de cinco peixes pirapitinga de piscicultura em Rolim de Moura-RO. Nos locais parasitados não foram observados inflamação e nem nódulos fibrosos. Ao estereomicroscópio foram identificados como P. gamitanae, todos fêmeas adultas fecundadas, possuíam dois sacos de ovos cada. Os estudo de parasitos de peixes que causam prejuízos à piscicultura é uma área em expansão e necessita de mais estudos para entender os mecanismos de ação dos parasitos, e assim, evitar doenças e mortalidade do plantel. P. gamitanae demonstrou que pode adaptar-se a novos hospedeiros, o que pode levar a um aumento do potencial de infestação e aumentar sua distribuição geográfica.(AU)
There are constant reports of fish parasites in the state of Rondônia, Brazil. Crustaceans are important parasites that cause damage to farmed fish. They have a great diversity of species and call attention because they are macroscopic in the parasitic phase and present wide variation of shape and size. Thus, the present study aims to report the identification of Perulernaea gamitanae (Crustacea: Lernaeidae) for the first time in pirapitinga fish (Piaractus brachypomus). Parasitic lipids were collected in the tongue of five pirapitinga fish from fish farming in Rolim de Moura-RO. In the parasitized sites no inflammation and no fibrous nodules were observed. To the stereomicroscope were identified as P. gamitanae, all adult females fertilized, they had two bags of eggs each. The study of fish parasites that cause damage to fish farming is an expanding area and requires more studies to understand the mechanisms of action of parasites, and thus avoid diseases and mortality of the establishment. P. gamitanae has shown that it can adapt to new hosts, which can lead to an increase in infestation potential and increase its geographical distribution.(AU)
Assuntos
Animais , Peixes/parasitologia , Copépodes/parasitologia , Characidae/parasitologia , Pesqueiros , BrasilRESUMO
São constantes os relatos de parasitos de peixes de cultivo no estado de Rondônia, Brasil. Os crustáceos são importantes parasitos que ocasionam prejuízos aos peixes cultivados. Possuem uma grande diversidade de espécies e chamam a atenção por serem macroscópicos na fase parasitária e apresentarem ampla variação de forma e tamanho. Dessa forma, o presente estudo objetiva relatar a identificação de Perulernaea gamitanae (Crustacea: Lernaeidae) pela primeira vez em peixes pirapitinga (Piaractus brachypomus). Foram coletados lerneídeos parasitos na língua de cinco peixes pirapitinga de piscicultura em Rolim de Moura-RO. Nos locais parasitados não foram observados inflamação e nem nódulos fibrosos. Ao estereomicroscópio foram identificados como P. gamitanae, todos fêmeas adultas fecundadas, possuíam dois sacos de ovos cada. Os estudo de parasitos de peixes que causam prejuízos à piscicultura é uma área em expansão e necessita de mais estudos para entender os mecanismos de ação dos parasitos, e assim, evitar doenças e mortalidade do plantel. P. gamitanae demonstrou que pode adaptar-se a novos hospedeiros, o que pode levar a um aumento do potencial de infestação e aumentar sua distribuição geográfica.
There are constant reports of fish parasites in the state of Rondônia, Brazil. Crustaceans are important parasites that cause damage to farmed fish. They have a great diversity of species and call attention because they are macroscopic in the parasitic phase and present wide variation of shape and size. Thus, the present study aims to report the identification of Perulernaea gamitanae (Crustacea: Lernaeidae) for the first time in pirapitinga fish (Piaractus brachypomus). Parasitic lipids were collected in the tongue of five pirapitinga fish from fish farming in Rolim de Moura-RO. In the parasitized sites no inflammation and no fibrous nodules were observed. To the stereomicroscope were identified as P. gamitanae, all adult females fertilized, they had two bags of eggs each. The study of fish parasites that cause damage to fish farming is an expanding area and requires more studies to understand the mechanisms of action of parasites, and thus avoid diseases and mortality of the establishment. P. gamitanae has shown that it can adapt to new hosts, which can lead to an increase in infestation potential and increase its geographical distribution.
Assuntos
Animais , Characidae/parasitologia , Copépodes/parasitologia , Peixes/parasitologia , Brasil , PesqueirosRESUMO
Copepods are hosts to various oomycete parasite species, but the effects of pathogens on copepod populations have rarely been studied. This study aimed to characterize oomycete infection in the freshwater copepod Parabroteas sarsi in a temporary pond in Patagonia (Argentina). A complete hydroperiod was monitored, evaluating environmental variables as influencing factors in the oomycete infections. Laboratory experiments were performed to evaluate the susceptibility of infected copepods to consumption by predators. Although 5 species of copepods were present in the pond, only ovigerous P. sarsi females were parasitized by oomycetes. Two species of oomycetes were always found together: Aphanomyces ovidestruens and Pythium flevoense. Infections were detected at water temperatures >20°C, with a positive relationship between temperature and parasite prevalence. Infection occurred after a decrease in large filter-feeder densities. The pathogens were not lethal to P. sarsi females in the short-term, but did produce mortality of entire egg sacs, thus negatively impacting subsequent recruitment. Mean prevalence of infection in females was 53%, reaching 83% in December. Females have the capacity to release an infected egg sac and generate a new one in a few days. This infection does not affect the susceptibility of P. sarsi to the predator Notonecta vereertbruggheni. The decrease in female abundance registered towards the end of the hydroperiod could be related to a combination of factors that may have a differential effect on female survival, such as increasing temperature, the energy cost of egg sac development and carrying and oomycete infection.
Assuntos
Copépodes/parasitologia , Oomicetos/fisiologia , Animais , Argentina , Feminino , Interações Hospedeiro-Parasita , Masculino , Estações do AnoRESUMO
Parasitic copepods of the family Lernaeidae are often found infesting freshwater fishes worldwide. They cause lernaeosis, a disease that can lead to serious pathogenic effects on their fish hosts. The most common lernaeid is the Lernaea cyprinacea, which has been widely introduced through importation of tropical fishes, e.g. cyprinids. In South America, it is one of the most common parasites both in wild and in farmed fish in the central region of Argentina. The silverside Odontesthes bonariensis is the most important fish of the sport fisheries of Argentina and one of the fish most affected by lernaeosis. Six specimens of copepods were collected from 30 specimens of O. bonariensis collected in a Pampean shallow lake (33°25'28S 62°53'56W) of Córdoba (Argentina). The 28S rRNA gene of L. cyprinacea was amplified by means of PCR to obtain the 28S rDNA sequence. The sequence obtained of this parasite from Argentina showed high genetic similarity with those from various geographical origins. The present study provided molecular characterization of L. cyprinacea in South America for the first time.(AU)
Os copépodos parasitos da família Lernaeidae são frequentemente encontrados infestando peixes de água doce em todo o mundo, causando a lernaeose, uma doença que pode levar a graves efeitos patogênicos em seus hospedeiros. O lerneídeo mais comum é a Lernaea cyprinacea, que tem sido amplamente introduzida por meio da importação de peixes tropicais, tais como ciprinídeos. Na América do Sul, é um dos parasitos mais comuns em peixes selvagens, bem como em peixes de cultivo na região central argentina. Odontesthes bonariensis é um dos peixes mais importantes para a pesca esportiva na Argentina e um dos mais afetados pela lerneose. Um total de seis espécimes desses copépodes foram coletados de espécimes de 30 O. bonariensis capturados em um lago de pouca profundidade nos Pampas (33°2528S 62°5356W) em Córdoba (Argentina). O gene 28S rRNA de L. cyprinacea foi amplificado por PCR para obter a sequência do 28S rDNA. A sequência obtida desse parasito da Argentina mostrou alta similaridade genética com aquelas de outras origens geográficas. O presente estudo forneceu, pela primeira vez, uma caracterização molecular de L. cyprinacea na América do Sul.(AU)
Assuntos
Animais , Copépodes/parasitologia , Doenças dos Peixes/parasitologia , Peixes/parasitologia , Reação em Cadeia da PolimeraseRESUMO
We analysed the association between a monogenean (Udonella cf. caligorum Johnston 1835) and its copepod host (Caligus sp.) living on a wild population of Arius herzbergii Bloch, 1794 in a north-eastern coastal lagoon from Venezuela. This study characterized infestation levels and analysed the effects of monogeneans on the fecundity and hatching success of the copepod host, as well as damage to its egg capsules and genital complex. A total of 218 Caligus specimens were analysed (94 males, 110 females and 14 immature stages) in which a total of 1017 monogeneans were found. These included 311 mature stages and 706 egg capsules. Monogenean stages were found attached to the cephalothorax, abdomen, genital complex and egg capsules of the copepods. No significant differences were found in fecundity and egg hatching when infested and non-infested ovigerous females were compared. No damage was observed on egg capsules or genital areas of infested ovigerous females. Our results suggest that this association, at the level of prevalence and intensity observed, is closer to commensalism than parasitism. The importance of considering that the nature of interaction is dynamic and changing with environmental conditions and time scale is highlighted.
Assuntos
Peixes-Gato/fisiologia , Copépodes/parasitologia , Interações Hospedeiro-Parasita , Trematódeos/fisiologia , Animais , Copépodes/anatomia & histologia , Ectoparasitoses/epidemiologia , Ectoparasitoses/parasitologia , Fertilidade , Lagos/parasitologia , Simbiose , Venezuela/epidemiologiaRESUMO
Parasitic copepods of the family Lernaeidae are often found infesting freshwater fishes worldwide. They cause lernaeosis, a disease that can lead to serious pathogenic effects on their fish hosts. The most common lernaeid is the Lernaea cyprinacea, which has been widely introduced through importation of tropical fishes, e.g. cyprinids. In South America, it is one of the most common parasites both in wild and in farmed fish in the central region of Argentina. The silverside Odontesthes bonariensis is the most important fish of the sport fisheries of Argentina and one of the fish most affected by lernaeosis. Six specimens of copepods were collected from 30 specimens of O. bonariensis collected in a Pampean shallow lake (33°25'28S 62°53'56W) of Córdoba (Argentina). The 28S rRNA gene of L. cyprinacea was amplified by means of PCR to obtain the 28S rDNA sequence. The sequence obtained of this parasite from Argentina showed high genetic similarity with those from various geographical origins. The present study provided molecular characterization of L. cyprinacea in South America for the first time.(AU)
Os copépodos parasitos da família Lernaeidae são frequentemente encontrados infestando peixes de água doce em todo o mundo, causando a lernaeose, uma doença que pode levar a graves efeitos patogênicos em seus hospedeiros. O lerneídeo mais comum é a Lernaea cyprinacea, que tem sido amplamente introduzida por meio da importação de peixes tropicais, tais como ciprinídeos. Na América do Sul, é um dos parasitos mais comuns em peixes selvagens, bem como em peixes de cultivo na região central argentina. Odontesthes bonariensis é um dos peixes mais importantes para a pesca esportiva na Argentina e um dos mais afetados pela lerneose. Um total de seis espécimes desses copépodes foram coletados de espécimes de 30 O. bonariensis capturados em um lago de pouca profundidade nos Pampas (33°2528S 62°5356W) em Córdoba (Argentina). O gene 28S rRNA de L. cyprinacea foi amplificado por PCR para obter a sequência do 28S rDNA. A sequência obtida desse parasito da Argentina mostrou alta similaridade genética com aquelas de outras origens geográficas. O presente estudo forneceu, pela primeira vez, uma caracterização molecular de L. cyprinacea na América do Sul.(AU)
Assuntos
Animais , Peixes/parasitologia , Copépodes/genética , Copépodes/parasitologiaRESUMO
Bomolochidae Claus, 1875 is a copepod family with worldwide distribution that parasitizes marine fishes. This study provides the first report of Hamaticolax scutigerulus (Wilson, 1935) (Copepoda: Bomolochidae) in the spotted goatfish Pseudupeneus maculatus (Bloch, 1793), in the coastal waters of Pernambuco, northeastern Brazil. Prevalence of 35%, mean intensity of infestation of 1.9±1.3 and mean abundance of 0.7±1.2 were found. The setae and spines of the leg armor of the Hamaticolax species were analyzed to identify the present species.(AU)
Bomolochidae Claus, 1875, é uma família de copépodes cujas espécies encontram-se amplamente distribuídas pelo mundo e são parasitas de peixes marinhos. Este estudo relata, pela primeira vez, Hamaticolax scutigerulus (Wilson, 1935) (Copepoda: Bomolochidae) no saramunete Pseudupeneus maculatus (Bloch, 1793) do litoral de Pernambuco, nordeste do Brasil. Prevalência de 35%, intensidade média de infestação de 1,9±1,3 e abundância média de 0,7±1,2 foram observadas. As setas e os espinhos da armadura das pernas do parasito das espécies de Hamaticolax foram analisadas para identificar a presente espécie.(AU)
Assuntos
Animais , Copépodes/classificação , Copépodes/parasitologiaAssuntos
Animais , Feminino , Bass/parasitologia , Copépodes/classificação , Copépodes/parasitologiaRESUMO
The dinoflagellate genus Chytriodinium, an ectoparasite of copepod eggs, is reported for the first time in the North and South Atlantic Oceans. We provide the first large subunit rDNA (LSU rDNA) and Internal Transcribed Spacer 1 (ITS1) sequences, which were identical in both hemispheres for the Atlantic Chytriodinium sp. The first complete small subunit ribosomal DNA (SSU rDNA) of the Atlantic Chytriodinium sp. suggests that the specimens belong to an undescribed species. This is the first evidence of the split of the Gymnodinium clade: one for the parasitic forms of Chytriodiniaceae (Chytriodinium, Dissodinium), and other clade for the free-living species.
Assuntos
Dinoflagellida/classificação , Dinoflagellida/genética , Filogenia , Animais , Oceano Atlântico , Análise por Conglomerados , Copépodes/parasitologia , DNA de Protozoário/química , DNA de Protozoário/genética , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Dinoflagellida/isolamento & purificação , RNA Ribossômico/genética , RNA Ribossômico 18S/genética , Análise de Sequência de DNARESUMO
Anisakids use invertebrates as paratenic and/or intermediate hosts as a basic feature of larval transmission. The third-stage larva usually develops in invertebrates which are prey items of finfish paratenic hosts. Contracaecum larvae molt twice inside the egg and hatch as free third-stage larvae ensheathed in the second-stage larval cuticle. Copepods act as paratenic or obligatory hosts, usually ingesting these free L3 larvae, and fish act as intermediate/paratenic or metaparatenic hosts preying on infected copepods. Fish-eating birds acquire L3 larvae by ingesting infected fish where they develop into the fourth-stage larvae and adults. Objectives of this work were to establish the specific correspondence between Contracaecum pelagicum L3 larvae parasitizing the anchovy Engraulis anchoita, and the adults parasitizing the Magellanic penguin Spheniscus magellanicus and the Imperial shag Phalacrocorax atriceps through the use of molecular markers; and, to evaluate the anisakid L3 larval recruitment and infection caused by ingestion of anchovy by S. magellanicus. Sixteen specimens of Contracaecum L3 larvae were analyzed from E. anchoita from Bahía Engaño, Chubut, eight adult nematodes from S. magellanicus and six adult specimens from P. atriceps both from the Valdés Peninsula, Chubut. All nematodes were sequenced for three genes: mitochondrial cytochrome oxidase 2 (mtDNA cox2), mitochondrial ribosomal RNA (rrnS), and the internal transcribed spacers (ITS-1 and ITS-2) of the nuclear ribosomal DNA region. Phylogenetic analyses were performed by using Maximum Parsimony (MP) analysis by PAUP. In addition, studies under SEM and LM were carried out on L3 larvae. All L3 individuals from E. anchoita, adults from S. magellanicus, and P. atriceps clustered in the same clade, well supported in the MP tree inferred from the mtDNA cox2, and rrnS gene sequences analyses. Further, the sequence alignments of L3 larvae and adults of C. pelagicum here obtained at the ITS-1 and ITS-2 regions of the rDNA matched the sequences of C. pelagicum previously deposited by us in GenBank. Nematode recruitment (Ro) was equal to 33.07 (7.20-91.14) L3 larvae for C. pelagicum in each penguin's meal of anchovy. The MP tree topologies obtained from mtDNA cox2 and rrnS genes demonstrated that specimens of Contracaecum L3 larvae from E. anchoita and C. pelagicum from S. magellanicus as well as from P. atriceps constitute a unique clade, well-distinct and supported from all the others formed by the Contracaecum spp. sequenced so far for these genes. Molecular markers are considered to be an effective tool to elucidate larval transmission. The Contracaecum L3 larval recruitment value showed that many worms fail to establish in the bird digestive tract, probably because they are below a critical size. Further work is needed to elucidate other factors (e.g., physiological, immunological) that control nematode populations in the penguin digestive tract.
Assuntos
Infecções por Ascaridida/veterinária , Ascaridoidea/classificação , Doenças das Aves/parasitologia , Doenças dos Peixes/parasitologia , Animais , Argentina , Infecções por Ascaridida/parasitologia , Infecções por Ascaridida/transmissão , Ascaridoidea/anatomia & histologia , Ascaridoidea/genética , Ascaridoidea/isolamento & purificação , Sequência de Bases , Doenças das Aves/transmissão , Aves , Copépodes/parasitologia , DNA de Helmintos/química , DNA de Helmintos/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Complexo IV da Cadeia de Transporte de Elétrons/química , Complexo IV da Cadeia de Transporte de Elétrons/genética , Doenças dos Peixes/transmissão , Peixes , Proteínas de Helminto/química , Proteínas de Helminto/genética , Larva , Microscopia Eletrônica de Varredura/veterinária , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase/veterinária , Alinhamento de Sequência/veterinária , Análise de Sequência de DNA/veterináriaRESUMO
Sea lice (Copepoda, Caligidae) are the most widely distributed marine pathogens in the salmon industry in the last 30 years. Caligus rogercresseyi is the most important species affecting Chile's salmon industry. Vaccines against caligid copepods have the potential to be a cost-effective means of controlling the infestation and avoid many of the disadvantages of medicine treatments. However, research in the development of such vaccines has begun only recently and approaches used thus far have met with little or no success. In the present study, we characterized a novel gene (denoted as my32) from C. rogercresseyi which has the highest identity with the Lepeophtheirus salmonis gene akirin-2. To assess the function of the gene an RNA interference experiment was developed and a reduction in the number of ectoparasites on fish in the my32-dsRNA treated group was observed. The recombinant my32 protein was used in a vaccination-challenge trial to evaluate its ability to protect against sea lice infestations. A significant reduction in the number of parasites per fish was observed at 24 days post-challenge. These results, together with the delay observed in the development of parasites from the vaccinated group suggest that the major effect of immunization was on the second parasite generation. The results of these experiments suggest that the my32 protein may be a promising target for vaccine development to control sea lice infestations in fish.
Assuntos
Copépodes/genética , Copépodes/parasitologia , Ectoparasitoses/veterinária , Doenças dos Peixes/prevenção & controle , Doenças Parasitárias em Animais/prevenção & controle , Vacinação/métodos , Animais , Copépodes/imunologia , Ectoparasitoses/imunologia , Ectoparasitoses/prevenção & controle , Doenças dos Peixes/imunologia , Inativação Gênica , Dados de Sequência Molecular , Doenças Parasitárias em Animais/imunologia , Análise de Sequência de DNA , Vacinas de Subunidades Antigênicas/administração & dosagem , Vacinas de Subunidades Antigênicas/imunologia , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/imunologiaRESUMO
The ciliate Trichodina was recorded on the calanoid Notodiaptomus deitersi in a shallow, eutrophic reservoir, located in the centre-west of Brazil. The species was confirmed as Trichodina diaptomi, a species widely distributed in Europe, Africa, Asia and Australia. It was observed moving freely over the carapace of the copepod, and using its adhesive disc. This is the first record for the species in the Americas.
Assuntos
Copépodes/parasitologia , Oligoimenóforos/isolamento & purificação , Animais , Brasil , Água Doce/parasitologia , Microscopia Eletrônica de Varredura , Oligoimenóforos/ultraestruturaRESUMO
Peritrich ciliates are commonly found as epibionts, colonizing living organisms, or attached to non-living substrates in freshwater, estuarine and marine environments. Several species of peritrich epibionts are obligate, which means that they are able to only colonize other organisms, while others are facultative attaching to living or non-living substrates. The peritrich Zoothamnium intermedium is commonly found as epibiont on the copepod species Acartia tonsa and Eurytemora affinis in Chesapeake Bay, USA. Previous studies demonstrated that Z. intermedium is not able to attach to non-living substrates in the laboratory; with free-swimming stages (telotrochs) dying when living substrates are not available for colonization. The present study investigated the ability of Z. intermdium to colonize artificial substrates in the field. Observations were carried out while the peritrich ciliate was colonizing copepods in Rhode River, a tributary of Chesapeake Bay. Results demonstrated that four species of Zoothamnium were recovered from artificial substrates, but none of them was Z. intermedium. At the same time, Z. intermedium was colonizing adults and copepodites of E. affinis and A. tonsa during the whole study period. These results, in addition to laboratory observations, suggest that Z. intermedium is an obligate epibiont.
Ciliados peritríquios são normalmente encontrados como epibiontes, colonizando substratos vivos, ou em substratos inanimados em ambientes de água doce, estuarinos e marinhos. Muitas espécies de peritríquios epibiontes podem ser consideradas obrigatórias quando estão aptas a colonizar apenas substratos vivos, ou facultativos quando conseguem colonizar substratos vivos ou inanimados. A espécie de ciliado peritríquio Zoothamnium intermedium é encontrada colonizando os copépodos Acartia tonsa e Eurytemora affinis na Chesapeake Bay, EUA. Estudos preliminares demonstraram que Z. intermedium não consegue colonizar substratos inanimados em laboratório e que os estágios livre-natantes (telotróquios) morrem quando não estão expostos a algum substrato vivo. No presente estudo, foi investigada a habilidade de Z. intermedium colonizar substratos artificiais no campo. As observações foram realizadas no Rhode River, um afluente da Chesapeake Bay, enquanto Z. intermedium era encontrado colonizando copépodos. Os resultados demonstraram que quatro espécies de Zoothamnium colonizaram os substratos artificiais, mas nenhuma delas era Z. intermedium. No mesmo período, Z. intermedium foi encontrado colonizando copepoditos e adultos de A. tonsa e E. affinis. Estes resultados, juntamente com as observações de laboratório, sugerem que Z. intermedium é um epibionte obrigatório.
Assuntos
Animais , Cilióforos/fisiologia , Copépodes/parasitologia , Cilióforos/crescimento & desenvolvimento , RiosRESUMO
Peritrich ciliates are commonly found colonizing living substrates. Although this a well known phenomenon, biological aspects of this relationship need to be studied in more detail. Assessment of growth rates in peritrichs has been the subject of very few studies. Only species in the genera Carchesium Ehrenberg, 1830 and Vorticella Linnaeus, 1767 had their growth rates evaluated in the field and in the laboratory. In the present study, growth, colonization (colonies/host), and proliferation (zooids/colony) rates of the peritrich epibiont Zoothamnium intermedium Precht, 1935 attached to the calanoid copepod Acartia tonsa Dana 1848 were evaluated in the laboratory in two food regimes: bacteria only, and algal based diet. Results showed that growth, colonization, and proliferation rates were similar for both diets. Maximum growth rates obtained for Z. intermedium was 0.85 and 0.83 per day, for bacteria and algae respectively. Maximum colonization rates were 0.5 per day for both diets, and the maximum proliferation rates were 0.44 and 0.42 per day for bacteria and algae respectively. These results demonstrate that Z. intermedium is able to grow at the same rate of other peritrichs on bacterial and algal based diets.
Assuntos
Cilióforos/crescimento & desenvolvimento , Copépodes/parasitologia , Dieta , Comportamento Alimentar/fisiologia , Laboratórios , Animais , Cilióforos/fisiologia , Fatores de TempoRESUMO
Peritrich ciliates are commonly found colonizing living substrates. Although this a well known phenomenon, biological aspects of this relationship need to be studied in more detail. Assessment of growth rates in peritrichs has been the subject of very few studies. Only species in the genera Carchesium Ehrenberg, 1830 and Vorticella Linnaeus, 1767 had their growth rates evaluated in the field and in the laboratory. In the present study, growth, colonization (colonies/host), and proliferation (zooids/colony) rates of the peritrich epibiont Zoothamnium intermedium Precht, 1935 attached to the calanoid copepod Acartia tonsa Dana 1848 were evaluated in the laboratory in two food regimes: bacteria only, and algal based diet. Results showed that growth, colonization, and proliferation rates were similar for both diets. Maximum growth rates obtained for Z. intermedium was 0.85 and 0.83 per day, for bacteria and algae respectively. Maximum colonization rates were 0.5 per day for both diets, and the maximum proliferation rates were 0.44 and 0.42 per day for bacteria and algae respectively. These results demonstrate that Z. intermedium is able to grow at the same rate of other peritrichs on bacterial and algal based diets.
Ciliados peritríquios são geralmente encontrados colonizando a superfície de outros organismos. Embora este fenômeno seja bem documentado, certos aspectos biológicos desta associação ainda precisam ser estudados. Taxas de crescimento em peritríquios foram objeto de pouquíssimos estudos, visto que apenas espécies nos gêneros Carchesium e Vorticella tiveram suas taxas de crescimento calculadas em experimentos de campo e de laboratório. No presente trabalho, taxas de crescimento, colonização (colônias/hospedeiro) e proliferação (zooides/colônia) do peritríquio epibionte Zoothamnium intermedium colonizando o copépodo calanoide Acartia tonsa foram avaliadas em laboratório com duas dietas: bactéria somente e alga. Resultados demonstraram que taxas de crescimento, colonização e proliferação foram semelhantes para as duas dietas. A taxa de crescimento máxima observada para Z. intermedium foi de 0.85 e 0.83 por dia para bactéria e alga, respectivamente. A taxa máxima de colonização foi 0.5 por dia para as duas dietas e a taxa máxima de proliferação foi de 0.44 e 0.42 por dia para bactéria e alga, respectivamente. Estes resultados demonstram que Z. intermedium cresce em taxas semelhantes a outras espécies de peritríquios em dietas de bactérias ou de algas.
Assuntos
Animais , Cilióforos/crescimento & desenvolvimento , Copépodes/parasitologia , Dieta , Comportamento Alimentar/fisiologia , Laboratórios , Cilióforos/fisiologia , Fatores de TempoRESUMO
Peritrich ciliates are commonly found as epibionts, colonizing living organisms, or attached to non-living substrates in freshwater, estuarine and marine environments. Several species of peritrich epibionts are obligate, which means that they are able to only colonize other organisms, while others are facultative attaching to living or non-living substrates. The peritrich Zoothamnium intermedium is commonly found as epibiont on the copepod species Acartia tonsa and Eurytemora affinis in Chesapeake Bay, USA. Previous studies demonstrated that Z. intermedium is not able to attach to non-living substrates in the laboratory; with free-swimming stages (telotrochs) dying when living substrates are not available for colonization. The present study investigated the ability of Z. intermdium to colonize artificial substrates in the field. Observations were carried out while the peritrich ciliate was colonizing copepods in Rhode River, a tributary of Chesapeake Bay. Results demonstrated that four species of Zoothamnium were recovered from artificial substrates, but none of them was Z. intermedium. At the same time, Z. intermedium was colonizing adults and copepodites of E. affinis and A. tonsa during the whole study period. These results, in addition to laboratory observations, suggest that Z. intermedium is an obligate epibiont.