The secondary lamellae of the gills are the primary sites of oxygen uptake in fish. We have used epi-illumination microscopy in vivo to observe the microcirculation directly in secondary lamellae of rainbow trout (Oncorhynchus mykiss) and roach (Rutilus rutilus). Our observations point at previously unrecognised factors in fish respiratory physiology. Erythrocytes passing through secondary lame...

The oxygen consumption rates of two cyprinid fishes, carp (Cyprinus carpio L.) and roach (Rutilus rutilus (L.)), were analysed for a wide range of body mass and swimming speed by computerized intermittent-flow respirometry. Bioenergetic models were derived, based on fish mass (M) and swimming speed (U), to predict the minimal speed and mass-specific active metabolic rate (AMR) in these fishes (...

We studied the association between environmental stress and epidermal papillomatosis of roach Rutilus rutilus L. in Finnish waters using a 'matched pairs' design. Populations impacted by industrial and/or sewage effluents were compared to reference populations from pristine sites. We examined both the prevalence (proportion of diseased fish) and intensity (number of scales covered by tumors) of...

During the years 2004-2006 the parasitological autopsies of three species of fish: roach Rutilus rutilus (L.), bream Abramis brama (L.) and perch Perca fluviatilis L. from three lakes situated in warmińsko-mazurskie voivodeship were done. The aim of this study was comparable analysis of Metazoan parasite communities which occur in roach, bream and perch in three lakes of river Łyna watershed. T...

The infection with Myxobolus intimus Zaika, 1965 in the gills of the roach Rutilus rutilus (L.) from Lake Balaton was recorded in 28 out of the 39 fish examined. Developing and mature plasmodia were detected on the gills exclusively in the spring. The Myxobolus intimus infection was found only in 2- to 3-year-old fish. In histological sections, young plasmodia were found in capillaries of the s...

The theory of island biogeography predicts that the probability of a species occupying an island depends on a dynamic equilibrium between extinction and colonization. Epidermal papillomatosis is a disease manifesting as skin tumours on fish. We studied the factors affecting the occurrence of the disease in roach, Rutilus rutilus (L.), in 34 lakes. The results of discrimination analysis suggest ...

Acoustic stimuli within the sonic range are effective triggers of C-type escape behaviours in fish. We have previously shown that fish have an acute sensitivity to infrasound also, with acceleration thresholds in the range of 10(-5) m s(-2). In addition, infrasound at high intensities around 10(-2) m s(-2) elicits strong and sustained avoidance responses in several fish species. In the present ...

1. By using a new video activity monitoring processor (Kaufmann, 1983) in conjunction with a large respirometer, we have measured swimming activity, oxygen consumption and reproductive investment (in the form of gonadal growth) of roach (Rutilus rutilus L.) during a seasonal cycle. 2. If the effect of temperature on metabolism is taken into account it can be shown that swimming activity is dras...