the aim of this investigation was to study macroscopic and microscopic structures of ovaries in barbus grypus of karoon river and their changes during annual maturation cycle. for this purpose, 120 adult  b.grypus with a mean weight of 835.0 to 1012.0 g, were caught from karoon river and transferred alive to the laboratory. after biometrical studies, the weights and morphological appearances of...

Fish-habitat associations are poorly known in offshore areas of very large rivers. We examined physical habitat structure and its effect on use assemblage formation benthic fishes the main channel Danube River, Hungary. Principal component analysis variables showed that sample unit (i.e., 500 m long reaches) cross-channel transect-level data corresponding reaches were highly correlated. found c...

La dieta y los hábitos alimentarios de una especie determinan su ubicación dentro red trófica definen rol ecológico. De esta manera, también representan un mecanismo clave en la estructuración mantenimiento estabilidad las comunidades. En el caso particular familia Ariidae, debido a sus estructuras óseas externas son escasos registros depredación sobre grupo, excepto algunos casos mamíferos mar...

Pathogenic Vibrio cholerae non-O1/non-O139 was isolated from the fry of the Cardinal tetra, Paracheirodon axelrodi and in adult Raphael catfish, Platydoras costatus kept in aquarium conditions. Further, an outbreak of vibriosis occurred in the wild populations of common nase, Chondrostoma nasus; chub, Squalius cephalus; gudgeon, Gobio gobio; stone loach, Barbatula barbatula; barbel, Barbus barb...

This work has been developed to examine the level of non-dioxin-like (ndl) PCBs (28, 52, 101, 138, 153 and 180) in (a) ten different freshwater fish species from the Danube river, (b) two sampling points: up and downstream of the industrial zone of the city of Pancevo (ecological hot spot in Serbia) and (c) two time points i.e., in 2001 and 2006. Obtained results would serve to analyse spatial,...

The organochlorine pesticides have been detected in the samples of sediment and muscle tissue of barbell (Barbus peloponnesius, Valenciennes, (1842); Barbus macedonicus, Karaman (1924), collected from the three natural lake ecosystems in the Republic of Macedonia, i.e. Lake Ohrid, Lake Prespa and Lake Dojran, in the period from 2004 to 2006. Special attention has been paid to the presence of th...

Functional traits are growing in popularity in modern ecology, but feeding studies remain primarily rooted in a taxonomic-based perspective. However, consumers do not have any reason to select their prey using a taxonomic criterion, and prey assemblages are variable in space and time, which makes taxon-based studies assemblage-specific. To illustrate the benefits of the trait-based approach to ...