Argentina’s Freshwater Systems, Aliens In Wonderland

To date a total of 34 alien taxa have been detected in Argentine freshwater systems. Knowledge about these organisms in terms of their actual spread and invasive status is scarce. Despite the existence of some laws regulating the import of foreign organisms, the issue if acknowledged by researchers does not occupy a prime position in research or official agendas. This is mostly due to a lack of awareness of the implications of alien aquatic invaders by policy makers, and the economic instability of the country, which has diverted funds into other areas considered more important. This paper focuses on generating a first assessment of the problem and designing a system that would allow for low-cost gathering of information regarding alien aquatic invaders, and making it readily available for researchers throughout Argentina.Facultad de Ciencias Naturales y Muse

Capítulo 7. Impactos de la erupción del complejo volcánico Puyehue-Cordón Caulle sobre lagos, lagunas, embalses y su biota

7. 1. IntroducciónLos ambientes lénticos del área afectada por la erupción del Complejo Volcánico Puyehue-Cordón Caulle (cvpcc) (figura 7. 1) consisten en pequeñas lagunas de alta montaña, lagunas de extensión y profundidad variables y lagos de gran profundidad (Calcagno, Fioriti, Pedrozo, Vigliano, López y otros, 1995). La mayor parte de los lagos en la zona se hallan ubicados en la depresión central que separa las altas cumbres al oeste de la estepa en el este. Todas las cuencas son de ori..

Capítulo 8. Impactos de la erupción del complejo volcánico Puyehue-Cordón Caulle sobre arroyos, ríos y su biota en la Patagonia andina

8. 1. IntroducciónLa región sur de los Andes (36º- 44º S 72º W) tiene alrededor de 50 volcanes activos que han sido, desde su formación inicial, elementos estructurantes de la evolución de los ecosistemas de la región (Ruzzante y Rabassa, 2011). Tanto sobre ambientes acuáticos como terrestres, históricamente se han reportado efectos de su actividad para varias zonas, entre ellas Caviahue y Copahue, cuyas inusuales condiciones ambientales han brindado la oportunidad de estudiar el efecto de e..

Effects of ploidy and nutritional conditions on muscle morphology, proliferation and myogenic proteins expression in Rhamdia quelen larvae

Although Rhamdia quelen is a promising species for farming in South America, many aspects of its development and optimal conditions of culture remain unknown. In this sense, we explore muscle development and some proteins related to myogenic process in diploid and triploid larvae submitted to fasting-refeeding. Regarding muscle morphology, within diploid groups, fasted larvae (FD) showed a significant decrease in white muscle fiber area compared with control (CD) and refed (RD-1) groups. Then, when food was provided, area values restored nearly to control. Based on these results, it is probable that temporary muscle fiber atrophy takes place in fasted diploid fish. Conversely, no significant morphological changes were observed among triploid groups. When the effects of ploidy on somatic growth were assessed, FD and RT-1 groups registered a significantly higher percentage of fibers with an area smaller than 500 μm2 compared with fasted triploid larvae (FT) and RD-1 groups, respectively. Additionally, immunolocalization of the proliferating cell nuclear antigen (PCNA) decreased during starvation in fish of both ploidies and only recovered to normal after refeeding in triploid fish. An increase in PCNA related to ploidy was detected in CD and RD-1 compared with their triploid counterparts. In relation to myogenic proteins, Myog showed a significant increase expression in diploid larvae during starvation. Mstn was not affected by ploidy or alimentary variations. Our results show that diploid fish are more affected by short-term starvation than triploid fish, which could be indicative of differential physiological responses of diploid and triploid larvae to alimentary changes in culture. This might be relevant to optimize conditions of culture for both diploid and triploid fish.Fil: Boaglio, Andrea Carolina. Universidad Nacional de Rosario. Facultad de Ciencias Veterinarias. Departamento de Ciencias Básicas. Cátedra de Histología y Embriología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Mendía Broda, Andrea Cecilia. Universidad Nacional de Rosario. Facultad de Ciencias Veterinarias. Departamento de Ciencias Básicas. Cátedra de Histología y Embriología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Muñoz, Lautaro H.. Universidad Nacional de Rosario. Facultad de Ciencias Veterinarias; ArgentinaFil: Mascambroni, Maria Belen. Universidad Nacional de Rosario. Facultad de Ciencias Veterinarias; ArgentinaFil: López, Pablo A.. Universidad Nacional de Rosario. Facultad de Ciencias Veterinarias; ArgentinaFil: Morón Alcain, Esteban. Universidad Nacional de Rosario. Facultad de Ciencias Veterinarias; ArgentinaFil: Arranz, Silvia Eda. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas; ArgentinaFil: Vigliano, Fabricio Andrés. Universidad Nacional de Rosario. Facultad de Ciencias Veterinarias. Departamento de Ciencias Básicas. Cátedra de Histología y Embriología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin