Primeiro relato de Lernaea cyprinacea (Copepoda: Lernaeidae) em girinos e rãs recém-metamorfoseadas em populações selvagens de Lithobates catesbeianus (Anura: Ranidae) na Argentina

Lernaea cyprinacea é um copépode ectoparasita que pode causar a morte do hospedeiro devido às hemorragias, ulcerações e infecções secundárias que provoca. Lernaea cyprinacea está amplamente distribuída na Argentina. Os relatos anteriores estão restritos quase que exclusivamente a casos de parasitismo em peixes; o parasitismo de larvas de anuros por copépodes tem sido raramente documentado. Este é o primeiro registro e descrição da infestação parasitária de L. cyprinacaea em girinos da espécie exótica e invasora Lithobates catesbeianus na Argentina. Um total de 15 girinos e 21 indivíduos recém-metamorfoseados de L. catesbeianus foi coletado na região serrana do Rio de los Sauces, e 12 girinos, no córrego Toledo. Foi encontrado um máximo de dois parasitas por hospedeiro, principalmente na cloaca. Foram observados sintomas clínicos de hemorragia, inflamação e úlceras na pele, com formação de muco na área de fixação dos parasitas.Lernaea cyprinacea is an ectoparasitic copepod that can result in the mortality of the host by causing hemorrhages, ulcerations, and secondary infections. Lernaea cyprinacea is widely distributed in Argentina. Previous reports are restricted almost exclusively to cases of parasitism in fishes; copepod parasitism of anuran larvae is rarely documented. This is the first record and description of the parasitic infestation of L. cyprinacaea on tadpoles of the exotic and invasive species Lithobates catesbeianus in Argentina. A total of 15 tadpoles and 21 newly-metamorphosed individuals of L. catesbeianus were collected from the mountain town of Río de los Sauces, and 12 tadpoles from the Toledo Stream. A maximum of two parasites per host was found, principally in the cloaca. Clinical symptoms of inflammation hemorrhage and ulcers in the skin with mucus formation in the attachment area of parasites were observed

Estudio comparativo de la frecuencia de micronúcleos y anormalidades nucleares en eritrocitos de tres especies ícticas Comparative studies of the frequency of micronuclei and nuclear abnormalities in erythrocytes of three species fishes

Los ecosistemas acuáticos cercanos a las zonas urbanas sufren un deterioro constante ocasionado por diversos factores físico-químicos relacionados con la actividad antrópica, representando un riesgo para los organismos que los habitan, en especial los peces. Estos efectos pueden ser biomonitoreados mediante técnicas de amplia utilización, como el Test de Micronúcleos (Mn) y el de Anormalidades nucleares (AN), entre otros. El objetivo de este trabajo fue verifcar y comparar la frecuencia de micronúcleos y anormalidades nucleares en tres especies ícticas colectadas en un lago urbano, Cyprinus carpio, Astyanax eigenmanniorum y Cheirodon interruptus. Luego de la captura y anestesia de los peces, se extrajo de cada individuo una muestra de sangre y se registró el peso y la longitud total. Las muestras fueron fjadas y luego teñidas con Giemsa al 10%, posteriormente se las analizó con microscopio (1000X) y se les tomaron fotografías con cámara digital. Se calculó, además, el índice de condición corporal (K) para cada uno de los ejemplares capturados. Se aplicó un análisis de correlación de rangos de Spearman (rs) entre frecuencia de Mn y AN vs K para cada especie. La prueba de Kruskal-Wallis se aplicó para evaluar diferencias de Mn y AN entre las especies. Los resultados no mostraron una correlación estadísticamente signifcativa (P> 0,05) entre las frecuencias de Mn y AN vs K. Las frecuencias de Mn entre las diferentes especies no arrojaron diferencias signifcativas (P> 0,05), mientras que las AN sí (P< 0,05). Astyanax eigenmanniorum fue la especie que mayor sensibilidad presentó. Las diferencias preliminares de AN entre las especies utilizadas, convierten a A. eigenmanniorum en una especie "centinela" y posible biomonitor de agentes xenobióticos.<br>Aquatic ecosystems near urban areas suffer a steady deterioration caused by physical and chemical factors related to human activity, representing a danger to organisms that inhabit them, especially the fsh. These effects may be biomonitored by widely used techniques, such as the Micronucleus Test (Mn) and Nuclear Abnormalities (NA), among others. The aim of this study was to verify and compare the frequency of micronuclei and nuclear abnormalities in three fsh species collected in an urban lake, Cyprinus carpio, Astyanax eigenmanniorum and Cheirodon interruptus. After the capture and anesthesia of the fsh, weight and length were registered, and a blood sample was obtained from each individual. The samples were fxed and stained with 10% Giemsa, subsequently they were analyzed with the microscope (1000X) and photographed with a digital camera. The body con-dition index (K) was calculated for each fsh caught. A correlation analysis Spearman rank (rs) between frequency of Mn and NA vs. K was performed for each species. The Kruskal-Wallis test was applied to assess differences in Mn and NA between species. The results showed no statistically signifcant correlation (P> 0.05) between the frequencies of Mn and NA vs K. The frequencies of Mn between different species yielded no signifcant differences (P> 0.05), whereas NA (P <0.05) did. A. eigenmanniorum was the most sensitive species. NA preliminary differences between the species used, convert A. eigenmanniorum in a sort of "sentinel specie" and a possible biomonitor of xenobiotic agents

Evaluation in situ of genotoxicity and stress in South American common toad Rhinella arenarum in environments related to fluorite mine

Little attention has been paid to the impact of wastewater generated by mining activities on fluoride. In this study, we evaluated the hematology responses of common South American toad Rhinella arenarum inhabiting natural and artificial environments associated with a fluorite mine from central Argentina. We analyzed three sampling stations associated with the fluorite mine: (I) Los Cerros Negros stream (CN), which runs on granitic rock with a high fluorite content; (II) Los Vallecitos stream (LV), which runs on metamorphic rock with low fluorite content; and (III) artificial decantation ponds (DP) containing sediments produced by fluorite flotation process. We calculated frequencies of micronuclei, erythrocyte nuclear abnormalities, mitosis, and immature erythrocytes. In addition, we performed a differential leukocyte count and determined neutrophils/lymphocyte ratio as a stress response estimator. We found high micronucleus (MN) and erythrocyte nuclear abnormality (ENA) frequencies in DP and CN but low frequencies in LV. The neutrophil/lymphocyte ratio was different among sites, with a significant increase in individuals from DP. Values registered in DP could be caused by exposure to mixture of compounds registered in dams that hold wastewater, while high values registered in CN stream might be due to natural concentrations of fluoride. Our results suggest that blood is an effective and non-destructive sensitive indicator for monitoring genotoxic agents in freshwater ecosystems.Fil: Pollo, Favio Ezequiel. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Ciencias Naturales. Cátedra de Ecología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Grenat, Pablo Raúl. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Ciencias Naturales. Cátedra de Ecología; ArgentinaFil: Salinas, Zulma Anahí. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Ciencias Naturales. Cátedra de Ecología; ArgentinaFil: Otero, Manuel Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Ciencias Naturales. Cátedra de Ecología; ArgentinaFil: Salas, Nancy Edith. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Ciencias Naturales. Cátedra de Ecología; ArgentinaFil: Martino, Adolfo Ludovico. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Ciencias Naturales. Cátedra de Ecología; Argentin