scholarly journals Genetic variability of brycon orbignyanus (valenciennes, 1850) (characiformes: characidae) in cultivated and natural populations of the upper paraná river, and implications for the conservation of the species

2011 ◽  
Vol 54 (4) ◽  
pp. 839-848 ◽  
Author(s):  
Renata de Souza Panarari-Antunes ◽  
Alberto José Prioli ◽  
Sônia Maria Alves Pinto Prioli ◽  
Alexsandro Sobreira Galdino ◽  
Horácio Ferreira Julio Junior ◽  
...  
2009 ◽  
Vol 7 (4) ◽  
pp. 623-628 ◽  
Author(s):  
Judy Ruiz Rezende ◽  
Erasmo Renesto ◽  
Cláudio Henrique Zawadzki

The genetic variability of three Gymnotus species from the Caracu stream, a small tributary of the left margin of Paraná River (Brazilian upper Paraná River floodplain), was estimated with data of 17 putative allozyme loci, which were obtained by using corn starch gel electrophoresis of 10 enzymatic systems: Aspartate aminotransferase (E. C. 2.6.1.1), Alcohol dehydrogenase (E. C. 1.1.1.1), Esterase (E. C. 3.1.1.1), Glucose dehydrogenase (E. C. 1.1.1.118), Glycerol-3-phosphate dehydrogenase (E. C. 1.1.1.8), Isocitrate dehydrogenase (E. C. 1.1.1.42), L-Lactate dehydrogenase (E. C. 1.1.1.27), Malate dehydrogenase (E. C. 1.1.1.37), Superoxide dismutase (E. C. 1.15.1.1) and Sorbitol dehydrogenase (E. C. 1.1.1.14). The genetic diversity was estimated as He = 0.3458 for G. pantanal, He = 0.2481 for G. inaequilabiatus, and He = 0.3152 for G. sylvius. The most divergent species were G. sylvius and G. pantanal (D = 0.117), and the most similar were G. inaequilabiatus and G. pantanal (D = 0.051). The data indicates that the observed genetic variability was very low and the expected variability estimated for these three species is very high, and the genetic differences among them are small. The data suggest that the process of speciation which produced these three species is recent.


1997 ◽  
Vol 20 (3) ◽  
pp. 381-388 ◽  
Author(s):  
Eloísa Revaldaves ◽  
Erasmo Renesto ◽  
Maria F.P.S. Machado

The genetic variability of the "curimba", Prochilodus lineatus, from three locations in the Paraná river basin, was investigated by starch gel electrophoresis. A total of 160 specimens were analyzed for 19 enzymes, 12 of which permitted successful interpretation of electrophoretic patterns. Eighteen loci were identified and six of them proved to be polymorphic (EST-1*, EST-2*, IDH-1*, PGM-1*, PGM-2*, LDH-2*). Mean heterozygosity was considered high (13%) by comparison with the literature. A low level of differentiation was found among subpopulations, with mean F ST = 0.018. Values of genetic distance and genetic identity suggest that, at least along this stretch of the river, P. lineatus comprises a single breed with high gene flow. This analysis has important implications for fishery management, aquaculture, and conservation of the stocks


2009 ◽  
Vol 69 (2 suppl) ◽  
pp. 707-716 ◽  
Author(s):  
EE. Souza Filho

The building of large dams in the Upper Paraná River basin altered the discharge regime at the Porto São José River section. The discharge regime has been altered since 1972, but the changes intensified after the Porto Primavera damming, in late 1998. Considering that discharge control affects the relationship between channel and floodplain, this work aimed to evaluate the intensity of the discharge control that resulted from the operation of the Porto Primavera Dam. To achieve this objective, statistical analyses were carried out based on the Porto São José Fluviometric Station historical series of river level readings and discharge, between 1964 and 2007. Results showed that the average discharge increased from 1964 to 1981 and diminished after river damming. The increase of average discharge rates was followed by an increase of the duration of higher discharges at different levels of geomorphologic and limnological importance, and the reduction of average discharge during the last observed period was followed by a disproportionate decrease in the duration of the abovementioned discharges. Moreover, it is clear that the relationship between fluviometric level and fluvial discharge changed, which implies that a certain river level reading represents a higher discharge than necessary before river damming.


2008 ◽  
Vol 25 (3) ◽  
pp. 419-426 ◽  
Author(s):  
Gabriela Ludwig ◽  
Lucas M. Aguiar ◽  
Walfrido K. Svoboda ◽  
Carmen L. S. Hilst ◽  
Italmar T. Navarro ◽  
...  

Howler monkeys (Alouatta Lacèpéde, 1799) are folivores-frugivores with flexible diets depending on conditions. Here, we compare the diets of Alouatta caraya (Humboldt, 1812) in two riparian forests (island and mainland), in Porto Rico region, Upper Paraná River, Southern Brazil. Howlers were followed from October 2004 to September 2005 in the riparian forest of a 1,050 ha island and in the continuous riparian forest on the mainland (left bank of the river). The "scan sampling" method with instantaneous samples every 15 minutes was used. Besides vines, diet breadth was similar: 17 species consumed on the island versus 16 species on the mainland. Both consumed leaves followed by fruits more than any other food type (leaves: island - 65%, mainland - 49%, fruits: island - 24%, mainland - 46%). Even though the plant Cecropia pachystachya Trécul is less abundant in the mainland it was the item most consumed in both locations all year long, which suggests its importance for the howlers. Diet also varied both seasonally and between the island and mainland, apparently following changes in local abundance of each item and due to plant phenologies.


Sign in / Sign up

Export Citation Format

Share Document