The Experts below are selected from a list of 570 Experts worldwide ranked by ideXlab platform
Vance L Trudeau - One of the best experts on this subject based on the ideXlab platform.
-
tadpoles of the horned frog Ceratophrys ornata exhibit high sensitivity to chlorpyrifos for conventional ecotoxicological and novel bioacoustic variables
Environmental Pollution, 2018Co-Authors: Salgado C Costa, Vance L Trudeau, Alicia Estela Ronco, Damian Jose Gabriel Marino, Guillermo Sebastian NataleAbstract:Abstract Previous studies reported that some species of the family Ceratophryidae are able to produce sounds during premetamorphic tadpole stages. We have now determined the effects of the cholinesterase-inhibiting insecticide chlorpyrifos (CPF) on sounds emitted by tadpoles of Ceratophrys ornata. Tadpoles were exposed individually in order to evaluate the progression of effects. Effects on sound production were complemented with common ecotoxicological endpoints (mortality, behavior, abnormalities and growth inhibition). C. ornata was found to be more sensitive than other native (= 67%, 50%) and non-native species (= 75%, 100%) considering lethal and sublethal endpoints, respectively. Effects on sounds appear along with alterations in swimming, followed by the presence of mild, then severe abnormalities and finally death. Therefore, sound production may be a good biomarker since it anticipates other endpoints that are also affected by CPF. Ceratophrys ornata is a promising new model species in ecotoxicology.
-
underwater sound emission as part of an antipredator mechanism in Ceratophrys cranwelli tadpoles
Acta Zoologica, 2014Co-Authors: Carolina Salgado Costa, Leandro Alcalde, Raul Herrera, Vance L Trudeau, Mariana Chuliver Pereyra, Guillermo Sebastian NataleAbstract:We report the emission of underwater sounds in the tadpoles of a second member of the family Ceratophryidae, Ceratophrys cranwelli. These tadpoles produce a short metallic-like sound, which consists of short trains of pulses at Gosner stages 25, 28, and 37. Experiment I was designed to record underwater sounds and their characteristics. Experiment II was designed to test: (i) if at higher densities (total number of tadpoles/L) but fixed predator–prey proportions C. cranwelli larvae are cannibalistic, (ii) if cannibalism increases at higher proportions of predators at a fixed density, and (iii) if tadpoles display a mechanism of intraspecific recognition that may diminish the frequency of cannibalism. Each treatment combines larvae of C. cranwelli (predator) with those of Rhinella arenarum (prey). The number of live and dead individuals was recorded during 72 h, and the following variables were calculated: time to eat the first and second prey, time without eating, time to eat a congener, and number of events of cannibalism. The results indicate that relative predator–prey availability affects the frequency of predation between conspecifics. We consider that an antipredator mechanism exists in C. cranwelli tadpoles and that the underwater sound is part of it.
-
underwater sound emission as part of an antipredator mechanism in Ceratophrys cranwelli tadpoles
Acta Zoologica, 2014Co-Authors: Carolina Salgado Costa, Leandro Alcalde, Raul Herrera, Vance L Trudeau, Mariana Chuliver Pereyra, Guillermo Sebastian NataleAbstract:Fil: Salgado Costa, Carolina. Universidad Nacional de la Plata. Facultad de Ciencias Exactas. Departamento de Quimica. Centro de Investigaciones del Medio Ambiente; Argentina. Consejo Nacional de Investigaciones Cientificas y Tecnicas; Argentina
-
underwater acoustic communication in the macrophagic carnivorous larvae of Ceratophrys ornata anura ceratophryidae
Acta Zoologica, 2011Co-Authors: Guillermo Sebastian Natale, Leandro Alcalde, Raul Herrera, Rodrigo Cajade, Eduardo Federico Schaefer, Federico Marangoni, Vance L TrudeauAbstract:Natale, G.S., Alcalde, L., Herrera, R., Cajade, R., Schaefer, E.F., Marangoni, F. and Trudeau, V.L. 2011. Underwater acoustic communication in the macrophagic carnivorous larvae of Ceratophrys ornata (Anura: Ceratophryidae). —Acta Zoologica (Stockholm) 92: 46–53. We provide the first evidence for sound production by anuran larvae. In this study, we describe the sounds, their context-specific emission and the structures related to sound production of the carnivorous larvae of Ceratophrys ornata (Amphibia, Anura, Ceratophryidae). Tadpoles emit a brief, clear and very audible metallic-like sound that consists of a short train of notes that occur at all stages of larval development. Tadpoles make sound only when a conspecific tadpole is preying upon it or when touched by an object. Ceratophrys ornata larvae possess the basic required anatomical structures for sound production via expulsion of atmospheric air from the lungs through the open soft-tissue glottis. The glottis is opened and closed via the larval laryngeal muscles (constrictor laryngis and dilatator laryngis). The arytenoid cartilages appear at stage 40 and the cricoid cartilage does at stage 43. Adult laryngeal muscles differentiate from the larval ones at stage 46 together with the vocal sac formation from the adult interhyoideus muscle. We demonstrate (n = 2160 conspecific predator–prey interactions) that larval sounds occur always under predatory attack, probably serving to diminish the chances of cannibalism. These data raise the possibility that other macrophagic carnivorous anuran larvae may produce sound.
-
Hormonal induction of spawning in 4 species of frogs by coinjection with a gonadotropin-releasing hormone agonist and a dopamine antagonist
Reproductive Biology and Endocrinology, 2010Co-Authors: Vance L Trudeau, Gustavo M Somoza, Guillermo S Natale, Bruce Pauli, Jacqui Wignall, Paula Jackman, Ken Doe, Fredrick W SchuelerAbstract:Background It is well known that many anurans do not reproduce easily in captivity. Some methods are based on administration of mammalian hormones such as human chorionic gonadotropin, which are not effective in many frogs. There is a need for simple, cost-effective alternative techniques to induce spawning. Methods Our new method is based on the injection of a combination of a gonadotropin-releasing hormone (GnRH) agonist and a dopamine antagonist. We have named this formulation AMPHIPLEX, which is derived from the combination of the words amphibian and amplexus. This name refers to the specific reproductive behavior of frogs when the male mounts and clasps the female to induce ovulation and to fertilize the eggs as they are laid. Results We describe the use of the method and demonstrate its applicability for captive breeding in 3 different anuran families. We tested several combinations of GnRH agonists with dopamine antagonists using Lithobates pipiens. The combination of des-Gly^10, D-Ala^6, Pro-LHRH (0.4 microrams/g body weight) and metoclopramide (10 micrograms/g BWt. MET) was most effective. It was used in-season, after short-term captivity and in frogs artificially hibernated under laboratory conditions. The AMPHIPLEX method was also effective in 3 Argentinian frogs, Ceratophrys ornata , Ceratophrys cranwelli and Odontophrynus americanus . Conclusion Our approach offers some advantages over other hormonally-based techniques. Both sexes are injected only once and at the same time, reducing handling stress. AMPHIPLEX is a new reproductive management tool for captive breeding in Anura.
Jane C Kaltenbach - One of the best experts on this subject based on the ideXlab platform.
-
apoptosis in larval and frog skin of rana pipiens r catesbeiana and Ceratophrys ornata
Journal of Morphology, 2014Co-Authors: Ellen E Faszewski, Selsebil Sljivo, Lisa Kriszun, Jane C KaltenbachAbstract:Apoptosis (programmed cell death) occurs during normal development of anurans in organs such as gills, gut, and tail. For example, apoptotic cells have been reported in the luminal epithelium along the length of the digestive tract of both larvae and frogs; however, timing of the peak number of such cells varies in different species. The purpose of the present study was to ascertain whether apoptosis also varies by species during metamorphic restructuring of the skin (as larval epithelium is replaced by adult epidermis). To determine this, cross-sections of dorsal skin from representative larval stages and frogs of Rana pipiens, R. catesbeiana, and Ceratophrys ornata were incubated with monoclonal antibody against active caspase-3, one of the main enzymes in the apoptotic cascade. We observed apoptotic cells in the epidermis of the skin of the three species and found that such cells were more numerous in larval stages than in frogs and more abundant in the two ranid species than in C. ornata. These results contribute to our understanding of metamorphic changes in anuran skin.
-
apoptosis in the digestive tract of herbivorous rana pipiens larvae and carnivorous Ceratophrys ornata larvae an immunohistochemical study
Journal of Morphology, 2012Co-Authors: Jane C Kaltenbach, Anne E Fry, Katherine M Colpitts, Ellen E FaszewskiAbstract:The lifespan of herbivorous Rana pipiens larvae is ∼3 months, while that of carnivorous Ceratophrys ornata larvae is only about 2 weeks. During metamorphic climax, the larval gut shortens dramatically, especially in R. pipiens, and its luminal epithelium is replaced by adult-type epithelium. To determine when programmed cell death occurs during the metamorphic restructuring of the gut, we prepared cross-sections of the stomach, small intestine, and large intestine from representative larval stages and from juvenile frogs of both species. The sections were incubated with monoclonal antibody against active caspase-3, one of the key enzymes in the apoptotic cascade. We observed apoptosis in some luminal epithelial cells in each of the three regions of the larval gastrointestinal tract of both species. However, apoptotic cells appeared earlier in larval stages of R. pipiens than C. ornata and few were seen in juvenile frogs of either species. The results demonstrate the occurrence of apoptosis in the metamorphic remodeling of the gut of both R. pipiens larvae and C. ornata larvae. J. Morphol., 2011. © 2011 Wiley Periodicals, Inc.
-
histology and lectin binding patterns in the skin of the terrestrial horned frog Ceratophrys ornata
Cell and Tissue Research, 1995Co-Authors: Ellen E Faszewski, Jane C KaltenbachAbstract:The terrestrial horned frog, Ceratophrys ornata, lives on a wet substratum and absorbs water through the ventral epidermis; water is lost by evaporation from the dorsal skin. Thus, this species may be useful as a model for determining whether or not skin histology and lectin-binding patterns, indicative of glycoconjugates, are related to skin functions such as osmoregulation and water balance. With this in mind, a histological and lectin-histochemical study was carried out on dorsal and ventral skin of aquatic tadpoles and of a young terrestrial frog of C. ornata. Sections of skin were stained with various dyes to demonstrate general histological features and with two horseradish peroxidase (HRP)-conjugated lectins, Ulex europaeus agglutinin (UEA 1) and soybean agglutinin (SBA) which bind to specific terminal sugar residues of glycoconjugates, namely L-fucose and N-acetyl-D-galactosamine or D-galactose, respectively. In early stage tadpoles both lectin-binding patterns were similar in the bilaminar epidermis of dorsal and ventral skin (i.e., each lectin stained the apical cell layer). However, metamorphic changes resulted in a young frog with typical adult-type skin composed of a stratified squamous epidermis and three distinct types of glands containing glycoconjugates in their secretions. Strikingly different lectin-binding patterns were evident in the epidermis from dorsal and ventral regions of the body. The epidermis from the dorsal region was stained by both lectins; in contrast, that from the ventral region although stained strongly by HRP-SBA, did not react with HRP-UEA 1 indicating that few, if any, fucose residues were present in the ventral epidermis. These findings, as suggested in the discussion, indicate that different glycoconjugate patterns in dorsal and ventral skin may be associated with the regulation of water balance in the frog.
Laura Nicoli - One of the best experts on this subject based on the ideXlab platform.
-
the fossil record of Ceratophrys wied neuwied anura ceratophryidae a revision and update of fossil south american horned frogs
Zootaxa, 2019Co-Authors: Laura NicoliAbstract:Ceratophrys is the most diverse and widely distributed genus of Ceratophryidae, the clade of South American horned frogs. Numerous anuran fossil remains, including several fossil species, have been assigned to this genus. However, this seemingly extensive fossil record is problematic because several of the fossils are not properly identified and most of the taxonomic assignations are not justified. The present study traces all the fossil material attributed to Ceratophrys, clarifying, when possible, institutional allocations. Each of the remains was examined and its taxonomic assignation revisited, based on the morphology and possible synapomorphies of the genus, including its living species. Numerous fossils were properly identified and assigned with certainty to Ceratophrys. Only one fossil species, Ceratophrys ameghinorum, is considered valid. This information, along with recently reported evidence of fossil Ceratophrys, is briefly summarized to serve as a practical reference for the entire known fossil record of the genus. The fossil record is not especially informative about the evolution or distribution pattern of Ceratophrys, because most of the remains are relatively young (post-Miocene), collected within the present distribution of the genus, and morphologically consistent with that of the extant species. However, some useful information has emerged. The presence of Ceratophrys is well documented since the Neogene in the Pampean Region of South America. The single valid fossil species, Ceratophrys ameghinorum, possesses a unique combination of characters that reflects a mixture of characters observed in different clades of the genus; thus, resolution of its phylogentic position will inform our understanding of the evolution of the genus. The paleoenvironmental significance of some Ceratophrys fossils is also discussed, addressing the wide, but incompletely known current distribution and environmental tolerance of the genus.
-
The oldest record of Ceratophrys (Anura, Ceratophryidae) from the Late Miocene of central Argentina
Journal of Vertebrate Paleontology, 2017Co-Authors: Laura Nicoli, Rodrigo Leandro Tomassini, Claudia I. MontalvoAbstract:SUPPLEMENTAL DATASupplemental materials are available for this article for free at www.tandfonline.com/UJVPCitation for this article: Nicoli, L., R. L. Tomassini, and C. I. Montalvo. 2017. The oldest record of Ceratophrys (Anura, Ceratophryidae) from the Late Miocene of central Argentina. Journal of Vertebrate Paleontology. DOI: 10.1080/02724634.2017.1261360.
-
The oldest record of Ceratophrys (Anura, Ceratophryidae) from the Late Miocene of central Argentina
2017Co-Authors: Laura Nicoli, Rodrigo Leandro Tomassini, Claudia I. MontalvoAbstract:Supplemental materials are available for this article for free at www.tandfonline.com/UJVP Citation for this article: Nicoli, L., R. L. Tomassini, and C. I. Montalvo. 2017. The oldest record of Ceratophrys (Anura, Ceratophryidae) from the Late Miocene of central Argentina. Journal of Vertebrate Paleontology. DOI: 10.1080/02724634.2017.1261360.
-
reappraisal of a ceratophryid frog from the oligocene of patagonia assignation to Ceratophrys and new insight about its provenance
Ameghiniana, 2014Co-Authors: Laura NicoliAbstract:Abstract. Fragmentary anuran remains in the Ameghino Collection in the Museo Argentino de Ciencias Naturales “Bernardino Rivadavia” were recently considered as belonging in Ceratophryidae (the clade of the South American horned frogs) and coming from middle—late Oligocene sediments exposed south of Lake Colhue Huapi, Chubut, Argentina. However, both the taxonomic placement and the geographic and stratigraphic origin attributed to this material are problematic. A new study of these remains show they possess several features that allow their attribution to the extant genus Ceratophrys Wied-Neuwied. The available information on the collection locality of this material is dubious —namely Gran Barranca, where rocks range from the middle Eocene to early Miocene in age. Additionally, details of the history of this collection and the specimen itself suggest that its provenance should better be considered unknown.
-
the oligocene of patagonia assignation to Ceratophrys and new insight about its provenance
2014Co-Authors: Laura Nicoli, Division Herpetologia, Investigaciones CientificasAbstract:Fragmentary anuran remains in the Ameghino Collection in the Museo Argentino de Ciencias Naturales "Bernardino Rivadavia" were recently considered as belonging in Ceratophryidae (the clade of the South American horned frogs) and coming from middle-late Oligocene sediments exposed south of Lake Colhue Huapi, Chubut, Argentina. However, both the taxonomic placement and the geographic and stratigraphic origin attributed to this material are problematic. A new study of these remains show they possess several features that allow their attribution to the extant genus Ceratophrys Wied-Neuwied. The available information on the collection locality of this material is dubious -namely Gran Barranca, where rocks range from the middle Eocene to early Miocene in age. Additionally, details of the history of this collection and the specimen itself suggest that its provenance should better be considered unknown.
Guillermo Sebastian Natale - One of the best experts on this subject based on the ideXlab platform.
-
tadpoles of the horned frog Ceratophrys ornata exhibit high sensitivity to chlorpyrifos for conventional ecotoxicological and novel bioacoustic variables
Environmental Pollution, 2018Co-Authors: Salgado C Costa, Vance L Trudeau, Alicia Estela Ronco, Damian Jose Gabriel Marino, Guillermo Sebastian NataleAbstract:Abstract Previous studies reported that some species of the family Ceratophryidae are able to produce sounds during premetamorphic tadpole stages. We have now determined the effects of the cholinesterase-inhibiting insecticide chlorpyrifos (CPF) on sounds emitted by tadpoles of Ceratophrys ornata. Tadpoles were exposed individually in order to evaluate the progression of effects. Effects on sound production were complemented with common ecotoxicological endpoints (mortality, behavior, abnormalities and growth inhibition). C. ornata was found to be more sensitive than other native (= 67%, 50%) and non-native species (= 75%, 100%) considering lethal and sublethal endpoints, respectively. Effects on sounds appear along with alterations in swimming, followed by the presence of mild, then severe abnormalities and finally death. Therefore, sound production may be a good biomarker since it anticipates other endpoints that are also affected by CPF. Ceratophrys ornata is a promising new model species in ecotoxicology.
-
underwater sound emission as part of an antipredator mechanism in Ceratophrys cranwelli tadpoles
Acta Zoologica, 2014Co-Authors: Carolina Salgado Costa, Leandro Alcalde, Raul Herrera, Vance L Trudeau, Mariana Chuliver Pereyra, Guillermo Sebastian NataleAbstract:We report the emission of underwater sounds in the tadpoles of a second member of the family Ceratophryidae, Ceratophrys cranwelli. These tadpoles produce a short metallic-like sound, which consists of short trains of pulses at Gosner stages 25, 28, and 37. Experiment I was designed to record underwater sounds and their characteristics. Experiment II was designed to test: (i) if at higher densities (total number of tadpoles/L) but fixed predator–prey proportions C. cranwelli larvae are cannibalistic, (ii) if cannibalism increases at higher proportions of predators at a fixed density, and (iii) if tadpoles display a mechanism of intraspecific recognition that may diminish the frequency of cannibalism. Each treatment combines larvae of C. cranwelli (predator) with those of Rhinella arenarum (prey). The number of live and dead individuals was recorded during 72 h, and the following variables were calculated: time to eat the first and second prey, time without eating, time to eat a congener, and number of events of cannibalism. The results indicate that relative predator–prey availability affects the frequency of predation between conspecifics. We consider that an antipredator mechanism exists in C. cranwelli tadpoles and that the underwater sound is part of it.
-
underwater sound emission as part of an antipredator mechanism in Ceratophrys cranwelli tadpoles
Acta Zoologica, 2014Co-Authors: Carolina Salgado Costa, Leandro Alcalde, Raul Herrera, Vance L Trudeau, Mariana Chuliver Pereyra, Guillermo Sebastian NataleAbstract:Fil: Salgado Costa, Carolina. Universidad Nacional de la Plata. Facultad de Ciencias Exactas. Departamento de Quimica. Centro de Investigaciones del Medio Ambiente; Argentina. Consejo Nacional de Investigaciones Cientificas y Tecnicas; Argentina
-
underwater acoustic communication in the macrophagic carnivorous larvae of Ceratophrys ornata anura ceratophryidae
Acta Zoologica, 2011Co-Authors: Guillermo Sebastian Natale, Leandro Alcalde, Raul Herrera, Rodrigo Cajade, Eduardo Federico Schaefer, Federico Marangoni, Vance L TrudeauAbstract:Natale, G.S., Alcalde, L., Herrera, R., Cajade, R., Schaefer, E.F., Marangoni, F. and Trudeau, V.L. 2011. Underwater acoustic communication in the macrophagic carnivorous larvae of Ceratophrys ornata (Anura: Ceratophryidae). —Acta Zoologica (Stockholm) 92: 46–53. We provide the first evidence for sound production by anuran larvae. In this study, we describe the sounds, their context-specific emission and the structures related to sound production of the carnivorous larvae of Ceratophrys ornata (Amphibia, Anura, Ceratophryidae). Tadpoles emit a brief, clear and very audible metallic-like sound that consists of a short train of notes that occur at all stages of larval development. Tadpoles make sound only when a conspecific tadpole is preying upon it or when touched by an object. Ceratophrys ornata larvae possess the basic required anatomical structures for sound production via expulsion of atmospheric air from the lungs through the open soft-tissue glottis. The glottis is opened and closed via the larval laryngeal muscles (constrictor laryngis and dilatator laryngis). The arytenoid cartilages appear at stage 40 and the cricoid cartilage does at stage 43. Adult laryngeal muscles differentiate from the larval ones at stage 46 together with the vocal sac formation from the adult interhyoideus muscle. We demonstrate (n = 2160 conspecific predator–prey interactions) that larval sounds occur always under predatory attack, probably serving to diminish the chances of cannibalism. These data raise the possibility that other macrophagic carnivorous anuran larvae may produce sound.
Maria Gabriela Agostini - One of the best experts on this subject based on the ideXlab platform.
-
human attitudes as threats in amphibians the case of the ornate horned frog Ceratophrys ornata
Human Dimensions of Wildlife, 2021Co-Authors: Camila Deutsch, Jimena Grisolia, David N Bilenca, Maria Gabriela AgostiniAbstract:We analyzed the characteristics of the human-animal conflict coming from the attitudes that local communities have toward Ceratophrys ornata, focusing on two threats: aversion and pet trade. Survey...