Diet of tadpoles of Physalaemus biligonigerus (Leiuperidae) from agricultural ponds in the central region of Argentina

The intensification of agriculture has led an important loss of natural habitats, with significant consequences for biodiversity. In this sense, the studies on anuran amphibian tadpoles inhabiting these environments are relevant, because the larval stage is a phase of population regulation. The aim of this study was to analyze the diet in Physalaemus biligonigerus tadpoles, an anuran species widely distributed in South America and that inhabit agroecosystems. Three sites were sampled; two agroecosystems with different alteration degrees (AG1 and AG2) and an uncultured (SM) third place. The captured tadpoles were anesthetized, fixed and preserved in formaldehyde (10%). Subsequently, the complete intestine was removed and analyzed for food items under a binocular microscope. The diet in P. biligonigerus tadpoles has a dominance of algae Bacillariophyceae, mainly in agroecosystems, due to the presence of the genera Navicula, Nitzschia and Gomphonema. There was a considerable abundance of the Gomphonema genus in the AG2 site. In addition, in the AG1 site several non-diatom algae were particularly abundant in the diet, such as the genera Euglena, Oedogonium and Chaetophora. In the SM site, the non-diatom genus Oscillatoria was well represented in the diet. Tadpoles inhabiting the site with abundant crop and livestock (AG1) ingested a significantly smaller amount of food. The presence of certain algae associated with eutrophic environments could indicate some pollution in agroecosystems (AG1 and AG2). Larval diet is suggested as a potential bioindicator of environmental health for these areas

Primeros registros de endoparásitos en cinco especies de anfibios anuros del litoral argentino

En el presente trabajo se brindan los primeros registros de endoparásitos en cinco especies de anfibios anuros del litoral argentino, contribuyendo al conocimiento sobre la diversidad parasitaria relacionada a estos vertebrados.Asociación Herpetológica Argentina (AHA

Seed storage conditions change the germination pattern of clonal growth plants in Mediterranean salt marshes.

8 páginas, 4 tablas, 8 figuras.The effect of salinity level and extended exposure to different salinity and flooding conditions on germination patterns of three saltmarsh clonal growth plants (Juncus subulatus, Scirpus litoralis, and S. maritimus) was studied. Seed exposure to extended flooding and saline conditions significantly affected the outcome of the germination process in a different, though predictable, way for each species, after favorable conditions for germination were restored. Tolerance of the germination process was related to the average salinity level measured during the growth/germination season at sites where established individuals of each species dominated the species cover. No relationship was found between salinity tolerance of the germination process and seed response to extended exposure to flooding and salinity conditions. The salinity response was significantly related to the conditions prevailing in the habitats of the respective species during the unfavorable (nongrowth/nongermination) season. Our results indicate that changes in salinity and hydrology while seeds are dormant affect the outcome of the seed-bank response, even when conditions at germination are identical. Because these environmental-history-dependent responses differentially affect seed germination, seedling density, and probably sexual recruitment in the studied and related species, these influences should be considered for wetland restoration and managementFinancial support from the Spanish Ministry of the Environment (MMA, project 05/99) and the Junta de Andalucía (research group 4086)enabled us to carry out the present work.Peer reviewe

Seed storage conditions change the germination pattern of clonal growth plants in Mediterranean salt marshes.

8 páginas, 4 tablas, 8 figuras.The effect of salinity level and extended exposure to different salinity and flooding conditions on germination patterns of three saltmarsh clonal growth plants (Juncus subulatus, Scirpus litoralis, and S. maritimus) was studied. Seed exposure to extended flooding and saline conditions significantly affected the outcome of the germination process in a different, though predictable, way for each species, after favorable conditions for germination were restored. Tolerance of the germination process was related to the average salinity level measured during the growth/germination season at sites where established individuals of each species dominated the species cover. No relationship was found between salinity tolerance of the germination process and seed response to extended exposure to flooding and salinity conditions. The salinity response was significantly related to the conditions prevailing in the habitats of the respective species during the unfavorable (nongrowth/nongermination) season. Our results indicate that changes in salinity and hydrology while seeds are dormant affect the outcome of the seed-bank response, even when conditions at germination are identical. Because these environmental-history-dependent responses differentially affect seed germination, seedling density, and probably sexual recruitment in the studied and related species, these influences should be considered for wetland restoration and managementFinancial support from the Spanish Ministry of the Environment (MMA, project 05/99) and the Junta de Andalucía (research group 4086)enabled us to carry out the present work.Peer reviewe

Doñana. Acta vertebrata. vol 24(1/2)

Alimentación de la lagartija colilarga Psammodromus algirus (L) (Sauria, Lacertidae), en el litoral de Huelva (SO EspañaLa alimentación de Myotis myotis Borkh, 1791 (Chiroptera, Vespertilionidae) en la cuenca del rio Guadix (sureste de España)Distribución y selección de hábitat de la garduña (Martes foina, Erxleben, 1777) en Vizcaya y Sierra Salvada (Burgos).Nuevo modelo de trampa para reducir el impacto de la pesca de cangrejos sobre los vertebrados en las marismas del GuadalquiviThe functions of song and the spatial pattern of song production in the rufous bush chat (Cercotrichas galactotes)Migración e invernada de las lavanderas cascadena Motacilla cinerea y blanca M. alba en la Penínula Ibérica e Islas BalearesAbundancia y reproducción de Glis glis (Linnaeus, 1766) (Rodentia, Gliridae) en el Pirineo occidental.Estatus de residencia, categorización trófica y abundancia de aves en el zoológico de La Plata, ArgentinaAvifauna reproductora y estructura del hábitat en la campiña y sierras Subbéticas de JaénDispersión de semillas de retama (Retama sphaerocarpa (L.) Boiss por el conejo (Oryctolagus cuniculus L.) en el centro de EspañaGuía para la identificación de restos óseos pertenecientes a algunos peces comunes en las aguas continentales de la Península Ibérica para el estudio de la dieta de depredadores ictiófagosDistribución y abundancia del corzo (Capreolus capreolus L. 1758) en la provincia de JaénAlimentación de las larvas de anuros en ambientes temporales del sistema del rio Paraná, Argentina.Mauremys leprosa como presa de Lutra lutraNota sobre la alimentación del lince ibérico en el Parque Natural de la Sierra de Andújar (Sierra Morena oriental)Presencia de Echinococcus granulosus (Cestoda) en un lobo ibérico (Canis lupusLa orientación de los nidos de paseriformes estepariosComparación de la dieta obtenida a partir de muestras estomacales y fecales del Tuco-tuco, Ctenomys mendocinus, en dos poblaciones de la precordillera de los Andes, ArgentinaEstructura genética y distribución de la variabilidad enzimática en poblaciones naturales de estornino negro (Sturnus unicolor)Estimación de la disponibilidad trófica para el quebrantahuesos (Gypaetus barbatus) en Cataluña (NE España) e implicaciones sobre su conservaciónPeer reviewe

Effect of diet on carboxylesterase activity of tadpoles (Rhinella arenarum) exposed to chlorpyrifos

An outdoor microcosm was performed with tadpoles (Rhinella arenarum) exposed to 125 μg L−1 chlorpyrifos and fed two types of food, i.e., lettuce (Lactuca sativa) and a formulated commercial pellet. Acetylcholinesterase (AChE) and carboxylesterase (CbE) activities were measured in liver and intestine after 10 days of pesticide exposure. Non-exposed tadpoles fed lettuce had an intestinal AChE activity almost two-fold higher than that of pellet-fed tadpoles. No significant differences were observed, however, in liver AChE activity between diets. Likewise, intestinal CbE activity – measured using two substrates, i.e. 1-naphthyl acetate (1-NA) and 4-nitrophenyl valerate (4-NPV) – was higher in tadpoles fed lettuce than in those fed pellets. However, the diet-dependent response of liver CbE activity was opposite to that in the intestine. Chlorpyrifos caused a significant inhibition of both esterase activities, which was tissue- and diet-specific. The highest inhibition degree was found in the intestinal AChE and CbE activities of lettuce-fed tadpoles (42–78% of controls) compared with pellet-fed tadpoles (<60%). Although chlorpyrifos significantly inhibited liver CbE activity of the group fed lettuce, this effect was not observed in the group fed pellets. In general, intestinal CbE activity was more sensitive to chlorpyrifos inhibition than AChE activity. This finding, together with the high levels of basal CbE activity found in the intestine, may be understood as a detoxification system able to reduce intestinal OP uptake. Moreover, the results of this study suggest that diet is a determinant factor in toxicity testing with tadpoles to assess OP toxicity, because it modulates levels of this potential detoxifying enzyme activity.Fil: Attademo, Andres Maximiliano. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas; ArgentinaFil: Sanchez Hernandez, Juan C.. Universidad de Castilla-La Mancha; EspañaFil: Lajmanovich, Rafael Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas; ArgentinaFil: Peltzer, Paola. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas; ArgentinaFil: Junges, Celina Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina. Universidad Nacional del Litoral. Facultad de Bioquímica y Ciencias Biológicas; Argentin

Hematological parameters of health status in the common toad Bufo arenarum in agroecosystems of Santa Fe Province, Argentina

We compared some hematological parameters and values of plasma cholinesterase activity in adult Bufo arenarum from a control site and agricultural sites. The mean values of the plasma cholinesterase activity did not vary among toads collected in pristine forest and agricultural sites. The blood parameters (hematocrit, hemoglobin concentration, white blood cells, and heterophils) from agricultural sites differed from the control site. The results suggest a high pesticide impact from intensive cropping in mid-eastern Santa Fe Province of Argentina.Fil: Cabagna, Mariana C.. Universidad Nacional del Litoral; ArgentinaFil: Lajmanovich, Rafael Carlos. Universidad Nacional del Litoral; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; ArgentinaFil: Stringhini, Gabriela. Universidad Nacional del Litoral; ArgentinaFil: Sanchez Hernandez, Juán C.. Universidad de Castilla-La Mancha; EspañaFil: Peltzer, Paola. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; Argentin