Results 21 to 30 of about 102 (84)

Ecology of endoparasites of the fluvial stingray Potamotrygon falkneri (Chondrichthyes: Potamotrygonidae) from the upper Paraná River floodplain, Brazil

Brazilian Journal of Biology
The present study investigated the ecological relationships between endoparasites and the host Potamotrygon falkneri from the upper Paraná River by using as indicators the host's relative condition factor (Kn), sex and hepatosomatic relation (HSR). Forty-
ACF. Lacerda, RM. Takemoto, GC. Pavanelli   +2 more
doaj   +1 more source

Length‒Weight and Length‒Length Relationships of Freshwater Fish Species Caught by Professional Fishermen in the Itaipu Reservoir, Brazil

Journal of Applied Ichthyology, Volume 2025, Issue 1, 2025.
Length‒weight relationships (LWRs) and length‒length relationships (LLRs) were estimated for 63 and 58 freshwater fish species, respectively, captured in the Itaipu Reservoir, Paraná River Basin, Paraná State, Brazil. Sampling was carried out from March 1987 to July 2024 at 63 professional fishing sites within the reservoir’s area of influence ...
Éder André Gubiani, Luiz Guilherme dos Santos Ribas, Anderson Luís Maciel, Geuza Cantanhêde, Laís Thayse Meier, Pitágoras Augusto Piana, Caroline Henn, Yintao Jia   +7 more
wiley   +1 more source

Serum chemistry, thyroxine concentration, and blood cell morphology of wild, young Blackchin Guitarfish Glaucostegus cemiculus sampled on the eastern Mediterranean coastline

Journal of Aquatic Animal Health, Volume 36, Issue 3, Page 281-299, September 2024.
Abstract Objective The Blackchin Guitarfish Glaucostegus cemiculus is endemic to the Mediterranean Sea and is critically endangered, but relevant routine laboratory data are unavailable. Our objectives were to determine the packed cell volume (PCV), comprehensive serum chemistry analytes, and serum total thyroxine (sTT4) concentration; compare serum ...
Nevo Schwartz, Danny Morick, Barak Azrieli, Aviad Scheinin, Dan Tchernov, Itamar Aroch   +5 more
wiley   +1 more source

Avaliação da citotoxicidade do extrato do ferrão de arraia Potamotrygon falkneri (Myliobatiformes:Potamotrygonidae) [PDF]

, 2017
Dissertação (mestrado)—Universidade de Brasília, Instituto de Ciências Biológicas, Programa de Pós-Graduação em Biologia Animal, 2015. ; Em diversas regiões brasileiras os acidentes provocados por arraias dulcícolas são temidos por serem causa comum de necrose tissular e infecções bacterianas secundárias, que frequentemente implicam em incapacidade ...
openaire   +2 more sources

Stirring, charging, and picking: hunting tactics of potamotrygonid rays in the upper Paraná River

Neotropical Ichthyology
Hunting tactics of potamotrygonid freshwater rays remain unreported under natural conditions. Three main foraging tactics of Potamotrygon falkneri and P. motoro are described here based on underwater observations in the upper Paraná River.
Domingos Garrone-Neto, Ivan Sazima
doaj   +1 more source

Activity and habitat use of two species of stingrays (Myliobatiformes: Potamotrygonidae) in the upper Paraná River basin, Southeastern Brazil

Neotropical Ichthyology
The life history of freshwater stingrays (Potamotrygonidae) under natural conditions has been poorly documented. In this study, we investigated theperiod of activity and the habitat use of two species of the genus Potamotrygon in the upper Paraná River ...
Domingos Garrone Neto, Virgínia Sanches Uieda   +1 more
doaj   +1 more source

The more stirring the better: cichlid fishes associate with foraging potamotrygonid rays

Neotropical Ichthyology
One hunting tactic of freshwater rays (Potamotrygonidae), termed "undulate the disc and stir substrate", is here reported to attract cichlids at two sites in the upper Paraná River.
Domingos Garrone-Neto, Ivan Sazima
doaj   +1 more source

Morfometria de raias continentais (Chondrichthyes, Potamotrygonidae) do alto rio Paraná, Brasil = Morphometry of upper Paraná river freshwater stingrays (Chondrichthyes, Potamotrygonidae)

Acta Scientiarum: Biological Sciences, 2007
Potamotrygonidae constitui o único grupo recente de Chondrichthyes cujo habitat está restrito, exclusivamente, a águas continentais. Na planície de inundação do Alto rio Paraná, espécies desta família estabeleceram-se após o fechamento das comportas da ...
Antonio Guilherme Cândido da Silva, Erivelto Goulart   +1 more
doaj  

Karyotype description and evidence of multiple sex chromosome system X1X1X2X2/X1X2Y in Potamotrygon aff. motoro and P. falkneri (Chondrichthyes: Potamotrygonidae) in the upper Paraná River basin, Brazil

Neotropical Ichthyology
Cytogenetic analysis of Potamotrygon aff. motoro and P. falkneri indicated the occurrence of an X1X1X2X2/X1X2 Y multiple sex chromosome system in both species, with 2n = 66 chromosomes for females and 2n = 65 chromosomes for males.
Vanessa Paes da Cruz, Cristiane Kioko Shimabukuro-Dias, Claudio Oliveira, Fausto Foresti   +3 more
doaj   +1 more source

Behavioural assessment of Potamotrygon stingrays under different food enrichment strategies

Frontiers in Ethology
IntroductionFreshwater stingrays of the genus Potamotrygon are endemic to South America and increasingly maintained in aquaria worldwide, yet welfare studies on these species remain limited.
Cassia Regina Ramos Gonzaga, Cristiano Schetini de Azevedo, Helen Colbachini, Laura Chrispim Reisfeld, Fabiana Lúcia André Padilha, Rafael Caprioli Gutierrez, Cristiane Schilbach Pizzutto, Cristiane Schilbach Pizzutto   +7 more
doaj   +1 more source