Growth and reproduction in captivity unveils remarkable life-history plasticity in the smallnose fanskate, Sympterygia bonapartii (Chondrichthyes: Rajiformes)

Analizamos el crecimiento y la reproducción de ejemplares de raya marmorada, Sympterygia bonapartii nacidas en cautiverio. Se obtuvieron ovicápsulas a partir de la oviposición de dos hembras capturadas en la naturaleza y mantenidas en el Acuario Temaikèn. Posteriormente a la eclosión, se analizó el crecimiento en 13 hembras y 21 machos hasta la madurez sexual. Se evaluó el patrón de oviposición y la performance reproductiva en seis de las hembras criadas en cautiverio. Se ajustaron cuatro modelos a los datos de crecimiento, entre los cuales la función logística fue la que logró el mejor ajuste. Para ambos sexos, la mayor tasa de crecimiento se registró durante el primer año de vida. Durante el segundo año, la tasa de crecimiento fue significativamente mayor en hembras que en machos. La talla de primera oviposición fue de 61,7 ± 3,5 cm LT, similar a la estimada en rayas silvestres. Sin embargo, las hembras criadas en cautiverio alcanzaron la madurez antes de los dos años de vida, es decir mucho antes que en el ambiente natural, lo que implica una plasticidad fenotípica significativa en esta especie. La similitud en la talla de madurez y la diferencia en la edad de madurez entre individuos cautivos y silvestres indican que hay un desacople de ambos parámetros mediado por la tasa de crecimiento. Los individuos nacidos en cautiverio se reprodujeron exitosamente y dejaron descendencia viable, lo que indica que el ambiente del Acuario Temaikèn es adecuado para que S. bonapartii complete su ciclo de vida.We analyzed growth and reproduction of captive-born smallnose fanskates Sympterygia bonapartii. Egg cases were obtained from oviposition of two females caught in the wild and held at Temaikèn Aquarium. Following hatching, growth was analyzed in 13 females and 21 males until sexual maturity. Pattern of oviposition activity and reproductive performance were evaluated in six of the captive-reared females. Four models were fitted to growth data, among which the logistic function was the one attaining the best fit. The highest growth rate for both sexes was recorded during the first year of life, whereas growth was significantly higher in females than in males during the second year. Size at first oviposition was 61.7 ± 3.5 cm TL, similar to wild specimens. However, captive-reared females reached maturity before two years of age, i.e. much earlier than wild skates, implying a significant phenotypic plasticity in this species. The similarity in size at maturity and the di ference in age at maturity between captive and wild specimens indicate that there is a decoupling of both parameters mediated through growth rates. Captive-born skates reproduced successfully and yielded viable offspring, indicating that the environment at Temaikèn Aquarium is suitable for S. bonapartii to attain its full life cycle.Fil: Jañez, Julieta. Fundación Temaikén; ArgentinaFil: Meijide, Fernando Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Biodiversidad y Biología Experimental y Aplicada. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad y Biología Experimental y Aplicada; ArgentinaFil: Lucifora, Luis Omar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Biología Subtropical. Universidad Nacional de Misiones. Instituto de Biología Subtropical; ArgentinaFil: Abraham, Carolina. Fundación Temaikén; ArgentinaFil: Argemi, Federico. Fundación Temaikén; Argentin

Characterization of ichthyocidal activity of Pfiesteria piscicida: Dependence on the dinospore cell density

The ichthyocidal activity of Pfiesteria piscicida dinospores was examined in an aquarium bioassay format by exposing fish to either Pfiesteria-containing environmental sediments or clonal P. piscicida. The presence of Pfiesteria spp. and the complexity of the microbial assemblage in the bioassay were assessed by molecular approaches. Cell-free water from bioassays that yielded significant fish mortality failed to show ichthyocidal activity. Histopathological examination of moribund and dead fish failed to reveal the skin lesions reported elsewhere. Fish larvae within "cages" of variable mesh sizes were killed in those where the pore size exceeded that of Pfiesteria dinospores. In vitro exposure of fish larvae to clonal P. piscicida indicated that fish mortality was directly proportional to the dinospore cell density. Dinospores clustered around the mouth, eyes, and operculi, suggesting that fish health may be affected by their direct interaction with skin, gill epithelia, or mucous surfaces. Molecular fingerprinting revealed the presence of a very diverse microbial community of bacteria, protists, and fungi within bioassay aquaria containing environmental sediments. Some components of the microbial community were identified as potential fish pathogens, preventing the rigorous identification of Pfiesteria spp. as the only cause of fish death. In summary, our results strongly suggest (i) that this aquarium bioassay format, which has been extensively reported in the literature, is unsuitable to accurately assess the ichthyocidal activity of Pfiesteria spp. and (ii) that the ichthyocidal activity of Pfiesteria spp. is mostly due to direct interactions of the zoospores with fish skin and gill epithelia rather than to soluble factors.Instituto de Limnología "Dr. Raul A. Ringuelet"Facultad de Ciencias Naturales y Muse

Assessing the impact of COVID-19 on liver cancer management (CERO-19).

BACKGROUND & AIMS: The coronavirus disease 2019 (COVID-19) pandemic has posed unprecedented challenges to healthcare systems and it may have heavily impacted patients with liver cancer (LC). Herein, we evaluated whether the schedule of LC screening or procedures has been interrupted or delayed because of the COVID-19 pandemic. METHODS: An international survey evaluated the impact of the COVID-19 pandemic on clinical practice and clinical trials from March 2020 to June 2020, as the first phase of a multicentre, international, and observational project. The focus was on patients with hepatocellular carcinoma or intrahepatic cholangiocarcinoma, cared for around the world during the first COVID-19 pandemic wave. RESULTS: Ninety-one centres expressed interest to participate and 76 were included in the analysis, from Europe, South America, North America, Asia, and Africa (73.7%, 17.1%, 5.3%, 2.6%, and 1.3% per continent, respectively). Eighty-seven percent of the centres modified their clinical practice: 40.8% the diagnostic procedures, 80.9% the screening programme, 50% cancelled curative and/or palliative treatments for LC, and 41.7% modified the liver transplantation programme. Forty-five out of 69 (65.2%) centres in which clinical trials were running modified their treatments in that setting, but 58.1% were able to recruit new patients. The phone call service was modified in 51.4% of centres which had this service before the COVID-19 pandemic (n = 19/37). CONCLUSIONS: The first wave of the COVID-19 pandemic had a tremendous impact on the routine care of patients with liver cancer. Modifications in screening, diagnostic, and treatment algorithms may have significantly impaired the outcome of patients. Ongoing data collection and future analyses will report the benefits and disadvantages of the strategies implemented, aiding future decision-making. LAY SUMMARY: The coronavirus disease 2019 (COVID-19) pandemic has posed unprecedented challenges to healthcare systems globally. Herein, we assessed the impact of the first wave pandemic on patients with liver cancer and found that routine care for these patients has been majorly disrupted, which could have a significant impact on outcomes

Impact of water salinity on Odontesthes bonariensis (Actinopterygii, Atherinopsidae) fisheries in Chasicó Lake (Argentina)

Odontesthes bonariensis is an inland water fish from the Pampas region, valued due to the quality of its flesh and its attractiveness as a game fish. Chasico´ Lake located in the south of the pampean region is appreciated by fishermen due to O. bonariensis abundance. However, in the last year, a reduction in their catches was recorded. In this work, it was analyzed the changes of O. bonariensis biomass in relation to climate change and salinity in Chasico´ Lake from 1997 to 2013. From 2004 to 2013, when a dry period began, a reduction in lake area (68.1?47.4 km2) and an increase in salinity (18.9?41.5 g l-1) were observed. O. bonariensis catches showed a significant decrease in the same period as a result of salinity increments. Possibly, at high salinity, O. bonariensis may still develop but with an impaired reproduction and limited embryo and juvenile survival. In conclusion, after 2004, the fishery quality in Chasico´ Lake showed a decreasing trend from the maximum registered in the Pampas lakes. This was in agreement with a marked decrease in the lake area which in turn increased water salinity up to levels close to the O. bonariensis tolerance limit.Fil: Berasain, Gustavo Emilio. Provincia de Buenos Aires. Ministerio de Asuntos Agrarios; ArgentinaFil: Colautti, Dario César. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Limnología "Dr. Raúl A. Ringuelet". Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología; ArgentinaFil: Remes Lenicov, Federico. Provincia de Buenos Aires. Ministerio de Asuntos Agrarios; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Argemi, Federico. Provincia de Buenos Aires. Ministerio de Asuntos Agrarios; ArgentinaFil: Bohn, Vanesa Yael. Universidad Nacional del Sur. Departamento de Geografía y Turismo; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Miranda, Leandro Andres. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús). Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús); Argentin

Large-scale migration of a school shark, Galeorhinus galeus, in the Southwestern Atlantic

El conocimiento sobre los patrones de distribución espacio-temporal de los condrictios es crítico para su manejo efectivo. En este trabajo presentamos y analizamos una migración latitudinal de gran escala (~ 1.425 km) de una hembra de cazón en la plataforma del Océano Atlántico Sudoccidental, donde está actualmente clasificada como Críticamente en Peligro. Durante el verano austral (15 de Febrero de 2015), 94 cazones fueron capturados (75 hembras y 19 machos) y señalados con marcas “rotatag” en el Golfo Nuevo (~ 42°43’S, 64°53’W, Argentina). Una hembra de 112 cm de longitud total fue recapturada en aguas de la plataforma uruguaya durante el invierno austral (17 de Agosto de 2015). Este gran desplazamiento representa la primera evidencia directa para apoyar la hipótesis de Vooren y Lucifora sobre una única población transnacional de Galeorhinus galeus en el Océano Atlántico Sudoccidental. La gran coincidencia encontrada entre las condiciones de hábitat para el cazón (salinidad 33-34, temperatura 12-17° C) y el integrante más cálido del Agua de Plataforma Subantártica sugiere que la variación estacional en la abundancia del cazón dentro de esta región podría estar relacionada con el movimiento de las masas de agua.Knowledge of the spatial and temporal distribution patterns of chondrichthyans is critical for their effective management. In this study we report and analyze a large-scale latitudinal migration (~ 1,425 km) of a female school shark in the Southwestern Atlantic shelf where it is currently classified as Critically Endangered. During the austral summer (February 15, 2015), ninety-four school sharks were captured (75 females and 19 males) and tagged with fin tags in Nuevo Gulf (~ 42°43"S, 64°53"W, Argentina). A female of 112 cm total length was recaptured in Uruguayan shelf waters in the austral winter (August 17, 2015). This long displacement represents the first direct evidence to support Vooren and Lucifora's hypothesis of a single transnational population of Galeorhinus galeus in the Southwestern Atlantic. The good agreement found between the school shark habitat conditions (salinity 33-34, temperature 12-17°C) and the warmer member of Subantarctic Shelf Waters suggests that the seasonal variation in school shark abundance within this region could be related to water masses movements.Fil: Jaureguizar, Andrés Javier. Instituto Nacional de Investigaciones y Desarrollo Pesquero; Argentina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; ArgentinaFil: Argemi, Federico. Fundación Temaikén; ArgentinaFil: Trobbiani, Gastón Andres. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; ArgentinaFil: Palma, Elbio Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Física del Sur. Universidad Nacional del Sur. Departamento de Física. Instituto de Física del Sur; ArgentinaFil: Irigoyen, Alejo Joaquin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; Argentin

Seasonality of Immunological and Health-State Parameters of Wild Broadnose Sevengill Shark, Notorynchus cepedianus

Seasonal fluctuation in environmental parameters can influence immune responses of vertebrates and consequently influence their health and disease resistance. Although seasonality of immune function is well documented in a broad range of vertebrate taxa, this information remains virtually unexplored in cartilaginous fish. Here we examine seasonal variation in immune and general-health parameters of free-living adult broadnose sevengill sharks, Notorynchus cepedianus, along an annual cycle. We sampled sharks during autumn/winter (i.e., coolest temperatures and nonreproductive period) and spring/summer (i.e., warmest temperatures and active reproductive period) and assessed aspects of immunity, general condition, and reproductive hormone levels. A seasonal influence was observed in some, but not all, parameters evaluated. Lower lymphocyte counts and higher heterophil counts and granulocyte to lymphocyte (G∶L) ratios were observed in sharks sampled during autumn/winter than in those sampled during spring/summer. On the other hand, total leukocyte counts, eosinophil counts, bacterial agglutination mediated by natural antibodies, and hematocrit did not vary seasonally. The observed seasonal patterns could be explained as (1) greater levels of stress based on the G∶L ratio, (2) a sign of immunosuppression or depressed immune investment based on the low lymphocyte counts, and/or (3) a sign of ongoing infection based on the higher heterophil counts in the colder seasons with respect to the warmer ones. In addition, the pattern is in line with the notion that while acquired components are usually depressed by lower temperatures, some innate components might increase to offset that reduction. Immune and health-state parameters were mostly independent of reproductive hormone levels, providing little support for a trade-off with reproduction. Overall, the observed seasonal pattern in immunity of broadnose sevengill sharks could be related to changes in abiotic environmental condition, such as water temperature and photoperiod, although other factors such as availability of high-quality food may play a part.Fil: Sueiro, Maria Cruz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; ArgentinaFil: Awruch, Cynthia Andrea. University of Tasmania; Australia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; ArgentinaFil: Irigoyen, Alejo Joaquin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; ArgentinaFil: Argemi, Federico. Aquarium Fundación Temaikèn; ArgentinaFil: Palacios, María Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; Argentin

Characterization of Ichthyocidal Activity of Pfiesteria piscicida: Dependence on the Dinospore Cell Density

The ichthyocidal activity of Pfiesteria piscicida dinospores was examined in an aquarium bioassay format by exposing fish to either Pfiesteria-containing environmental sediments or clonal P. piscicida. The presence of Pfiesteria spp. and the complexity of the microbial assemblage in the bioassay were assessed by molecular approaches. Cell-free water from bioassays that yielded significant fish mortality failed to show ichthyocidal activity. Histopathological examination of moribund and dead fish failed to reveal the skin lesions reported elsewhere. Fish larvae within “cages” of variable mesh sizes were killed in those where the pore size exceeded that of Pfiesteria dinospores. In vitro exposure of fish larvae to clonal P. piscicida indicated that fish mortality was directly proportional to the dinospore cell density. Dinospores clustered around the mouth, eyes, and operculi, suggesting that fish health may be affected by their direct interaction with skin, gill epithelia, or mucous surfaces. Molecular fingerprinting revealed the presence of a very diverse microbial community of bacteria, protists, and fungi within bioassay aquaria containing environmental sediments. Some components of the microbial community were identified as potential fish pathogens, preventing the rigorous identification of Pfiesteria spp. as the only cause of fish death. In summary, our results strongly suggest (i) that this aquarium bioassay format, which has been extensively reported in the literature, is unsuitable to accurately assess the ichthyocidal activity of Pfiesteria spp. and (ii) that the ichthyocidal activity of Pfiesteria spp. is mostly due to direct interactions of the zoospores with fish skin and gill epithelia rather than to soluble factors

Habitat use, seasonality and demography of an apex predator: Sevengill shark Notorynchus cepedianus in Northern Patagonia

Gaining insight on how species relate to their environment and other members of the trophic community is critical for their management. We investigated habitat use, seasonal patterns of abundance and population structure of the broadnose sevengill shark Notorynchus cepedianus in the marine temperate environment of a Northern Patagonian bay (Argentina). We expected N. cepedianus to exhibit strong seasonality in the bay driven by the seasonal occurrence of important marine mammal prey. However, an alternative or complementary hypothesis arose from the possibility that N. cepedianus uses the area seasonally as mating grounds. To explore these hypotheses, a suite of baited remote underwater video stations and catch per unit effort data indices were used to estimate the seasonal relative abundance of the species inside the bay. Reproductive hormone levels were measured to determine reproductive status and maturity stages of the population. Results indicated that N. cepedianus uses the bay year-round, showing a peak abundance during spring when individuals aggregate, likely for feeding and mating purposes. Male and female total lengths at maturity were 170 and 190 cm, respectively. Contrary to other studies in the Southwest Atlantic, population composition remained similar throughout the seasons, with adults dominating over juveniles, and adult females prevailing in the population at all times. Considering the historical abundance decline recently reported for the species, protection and enforcement within protected areas across the Southwest Atlantic must remain of high priority in government initiatives.Fil: Irigoyen, Alejo Joaquin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; ArgentinaFil: de Wysiecki, Agustín María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; ArgentinaFil: Trobbiani, Gastón Andres. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; ArgentinaFil: Bovcon, Nelson Darío. Provincia del Chubut. Secretaría de Pesca; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Awruch, Cynthia Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; Argentina. University of Tasmania; AustraliaFil: Argemi, Federico. Fundación Temaiken; ArgentinaFil: Jaureguizar, Andrés Javier. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; Argentina. Instituto Nacional de Investigaciones y Desarrollo Pesquero; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Alcohol-related liver disease is rarely detected at early stages compared with liver diseases of other etiologies worldwide

© 2019 by the AGA InstituteBackground & aims: Despite recent advances in treatment of viral hepatitis, liver-related mortality is high, possibly owing to the large burden of advanced alcohol-related liver disease (ALD). We investigated whether patients with ALD are initially seen at later stages of disease development than patients with hepatitis C virus (HCV) infection or other etiologies. Methods: We performed a cross-sectional study of 3453 consecutive patients with either early or advanced liver disease (1699 patients with early and 1754 with advanced liver disease) seen at 17 tertiary care liver or gastrointestinal units worldwide, from August 2015 through March 2017. We collected anthropometric, etiology, and clinical information, as well as and model for end-stage liver disease scores. We used unconditional logistic regression to estimate the odds ratios for evaluation at late stages of the disease progression. Results: Of the patients analyzed, 81% had 1 etiology of liver disease and 17% had 2 etiologies of liver disease. Of patients seen at early stages for a single etiology, 31% had HCV infection, 21% had hepatitis B virus infection, and 17% had nonalcoholic fatty liver disease, whereas only 3.8% had ALD. In contrast, 29% of patients seen for advanced disease had ALD. Patients with ALD were more likely to be seen at specialized centers, with advanced-stage disease, compared with patients with HCV-associated liver disease (odds ratio, 14.1; 95% CI, 10.5-18.9; P < .001). Of patients with 2 etiologies of liver disease, excess alcohol use was associated with 50% of cases. These patients had significantly more visits to health care providers, with more advanced disease, compared with patients without excess alcohol use. The mean model for end-stage liver disease score for patients with advanced ALD (score, 16) was higher than for patients with advanced liver disease not associated with excess alcohol use (score, 13) (P < .01). Conclusions: In a cross-sectional analysis of patients with liver disease worldwide, we found that patients with ALD are seen with more advanced-stage disease than patients with HCV-associated liver disease. Of patients with 2 etiologies of liver disease, excess alcohol use was associated with 50% of cases. Early detection and referral programs are needed for patients with ALD worldwide.This study was funded by the National Institute of Alcohol Abuse and Alcoholism grants U01AA021908 and U01AA020821, a scholarship grant from the Spanish Association for the Study of the Liver (M.V.-C.), and a grants NSFC 81570530 and 81370550 from the National Natural Science Foundation of China (L.Y.).info:eu-repo/semantics/publishedVersio