During high summer seasons in 1994-1999 84 big (20-42 cm total length) female perch (Perca fluviatilis L) were sampled from the waters around Tvärminne Zoological Station on the Hanko-Hangö peninsula on the SW coast of Finland for mercury analysis. Additional sampling of 13 big female perch during the same season were carried out from the waters of Nåtö Biological Station on the Aland Islands i...

The diet overlap between young-of-the-year (YOY) perch and burbot in the pelagic zone of Lake Constance during spring and summer was investigated in relation to gape size limitation. Because perch were larger and grew faster than burbot during their early life history, perch overcame gape size limitation for various zooplankton taxa earlier than burbot. The interspecific diet overlap between pe...

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Structurally complex environments strongly affect the behaviours and foraging efficiencies of predators and prey. I studied temporal variation in the habitat distribution of perch (Perca fluviatilis) and pike (Esox lucius) in relation to habitat complexity and prey abundance in a lake. The study involved quantitative estimates of different habitat types, estimates of macroinvertebrate prey avai...

In the modern broiler industry, solutions are still being sought to improve conditions or eliminate problems related to issues such as animal welfare, health, and meat quality brought by intensive production systems. Therefore, this experiment was conducted to study effects of perching on growth performance, carcass characteristics, and footpad lesions (FPLs) in broiler chickens. A total of 300...

The cDNA sequences encoding prolactin (PRL), somatolactin (SL) and insulin-like growth factor-I (IGF-I) genes of the yellow perch were obtained. Brain, pituitary, gill, heart, liver, stomach, kidney, spleen, muscle and gonad tissues were analyzed from both male and female adult yellow perch for sex-specific tissue expression. The full length cDNA of yellow perch PRL consists of 2306 bp and PRL ...

range, yellow perch, Perca flavescens, are viewed variously as a sport fish, a valuable food fish, an important forage species, or a nuisance trash fish with little commercial or sport value. Attitudes toward yellow perch vary with its relative availability and with historical regional preferences. In much of the midwestern and central Atlantic areas of the United States and in central Canada, ...

Reduced recruitment of yellow perch has been noted for a number of years in certain urbanized watersheds (South and Severn Rivers) of the Chesapeake Bay. Other rapidly developing watersheds such as Mattawoman Creek are more recently showing evidence of reduced recruitment of anadromous fishes. In this study, we used a battery of biomarkers to better document the reproductive health of adult yel...

Selection can alter predator-prey interactions. However, whether and how complex food-webs respond to selection remain largely unknown. We show in the field that antagonistic selection from predators and pathogens on prey body-size can be a primary driver of food-web functioning. In Windermere, U.K., pike (Esox lucius, the predator) selected against small perch (Perca fluviatilis, the prey), wh...

Domestication has altered a variety of traits within the Eurasian perch (Perca fluviatilis), including phenotypic, physiological and behavioral traits of Eurasian perch (Perca fluviatilis). Little is known, however, about the genetic changes between domesticated and wild Eurasian perch. In this study, we assembled a high-quality de novo reference transcriptome and identified differentially expr...