English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Experiments were designed to determine if the juvenile forms of jundia (Rhamdia quelen) exhibit selectivity feeding on zooplanktonic organisms and the influence of intraspecific competition on the diet. The fish were maintained in 5000-L containers, and after seven days from birth, they were acclimated in experimental units with different densities and supplied with water containing plankton (natural), where they remained for 24 h in the environment with food. In the first seven days at densities of 5 and 10 fish.L-1, the fish selected the Rotifera more intensely, and at densities of 20 and 40 fish.L-1, the Cladocera were more selected. At 14 days of age, the Cladocera were the most selected for all densities of fish. At 21 days of age, the juvenile forms of jundia maintained a preference for Cladocera, and there was an increase in the capture of Copepoda at a density of 40 fish.L-1. At 28 days of age, the Cladocera were the most captured at densities of 5 to 20 fish.L-1, and the consumption of copepods increased at a density of 40 fish.L-1. The juvenile forms of Rhamdia quelen showed a high feeding preference for Cladocera at all the ages tested (7, 14, 21 and 28 days), but the density of fish per litre influenced the capture of the preferential food. This study showed that the juvenile forms of jundia had a more rapid response to the presence of food at densities of more than 10 fish.L-1, and that at higher densities the fish decreased interactions of territorial defense and formed schools, which allowed the foraging of zooplanktonic organisms, larger in size, more agile and of greater energy gain, such as the Cladocera and copepods.

Feeding activity and influence of intraspecific competition on zooplankton communities by jundiá (Rhamdia quelen Quoy and Gaimard, 1824) in laboratory