Feeding strategy of the jundiá <em>Rhamdia quelen</em> (Siluriformes, Heptapteridae) in costal lagoons of southern Brazil

Abstract

Feeding strategy and mouth morphology of 'jundiá' in costal lagoons of south of Rio Grande do Sul were studied. Gut contend of 189 individuals were collected from 2002 to 2004 and analysed according Amundsen. Fishes and crustaceans were the feeding items more frequent in the diet. Mollusk, insects and plants had low FO%. Season variation in diet showed lower variety of feeding items during summer and higher in winter. The diet vary according to site were irrigation channels showed low FO% for all items. The 'jundiá' showed generalist feeding strategy, generally preying on fish and crustaceous. On the description of its feeding apparatus the importance on the capture prey was observed.

The autochthonous microbiota of the freshwater omnivores jundiá (Rhamdia quelen) and tilapia (Oreochromis niloticus) and the effect of dietary carbohydrates

“…Jundiá Rhamdia quelen (Quoy & Gaimard), an opportunistic omnivore, which has a varied diet that includes molluscs, crustaceans, fish, insects, detritus, algae and weeds (Castro & Casatti ; Kütter, de Azevedo Bemvenuti & Moresco ), has a short intestine and utilizes dietary carbohydrates less efficiently than other omnivores (Oliveira‐Filho & Fracalossi ; Moro, Camilo, Moraes & Fracalossi ; Rodrigues, Gominho‐Rosa, Cargnin‐Ferreira, de Francisco & Fracalossi ). However, tilapia Oreochromis niloticus L., a typical omnivore, which feeds predominantly on algae, plants and phytoplankton, has a long intestine and can tolerate and utilize higher levels of dietary carbohydrate (Leenhouwers, Pellikaan, Huizing, Coolen, Verreth & Schrama ).…”

Use of trophic ecology of omnivorous fish and abiotic factors as supporting tools for assessing environmental impacts in a neotropical river

“…However, , 2000). The species' intestinal tract is similar to that of carnivores (Baldisserotto, 2008), and the adaptations of its mouth apparatus allow it to select prey from the bottom of the river, and crush shells (Kütter, 2009), justifying the higher percentage of fish in the stomachs. Even with a lower percentage of mollusks, insects, and decapods as recorded by Casatti and Castro (2006), these were still present in the diet of the species, showing the species' omnivory (Pedrotti et al, 2015).…”

“…The composition of R. quelen 's food items and categories indicates that the species is omnivorous (Brandão‐Gonçalves & Sebastien, 2013; Gomes et al, 2000; Gomiero & Souza, 2007; Kütter, 2009) although tending toward carnivory (dos Santos & Meurer, 2020; Gomes et al, 2000). The species' intestinal tract is similar to that of carnivores (Baldisserotto, 2008), and the adaptations of its mouth apparatus allow it to select prey from the bottom of the river, and crush shells (Kütter, 2009), justifying the higher percentage of fish in the stomachs. Even with a lower percentage of mollusks, insects, and decapods as recorded by Casatti and Castro (2006), these were still present in the diet of the species, showing the species' omnivory (Pedrotti et al, 2015).…”

“…The anthropogenically impacted environment may also be related to the size and weight of the species, which are relatively smaller than those found in other settings(Albieri et al, 2014;Froese & Pauly, 2021), probably related to the fact that eutrophication can affect species in terms of biomass variation, positively or negatively favoring some fish species(de Mutsert et al, 2016). However, even with the reduced number of captures, we were able to estimate the diet composition of the analysed species, compatible with those described in the literature.The composition of R. quelen's food items and categories indicates that the species is omnivorous(Brandão-Gonçalves & Sebastien, 2013;Gomes et al, 2000;Gomiero & Souza, 2007;Kütter, 2009) although tending toward carnivory (dosSantos & Meurer, 2020;Gomes et al…”