Organisation of the Atlantic salmon (Salmo salar) thymus and its content of Ig-expressing cells.

The thymus of fishes is located as a dual organ in a rostrodorsal projection within the gill chamber and is covered by the operculum. The histological organization of the teleost fish thymus displays considerable diversity, particularly in salmonids where a clear distinction between the thymus cortex and medulla is yet to be defined. Recent interest has focused on the role of B cells in thymic function, but the presence of these cells within the salmon thymus remains poorly understood.

The Distribution of IgT mRNA Cells in the Gut of the Atlantic Salmon ( L.).

The newly discovered IgT B cell is thought to play a dominant role in mucosal immunity, but limited studies have examined its distribution in fish species, hindering our understanding of its function. This study investigated IgT and poly Ig receptor (pIgR) mRNA cell distribution in Atlantic salmon () gut using RNAscope in situ hybridization (ISH) and assessed the effects of vaccination. The pyloric caeca, mid-intestine (first and second parts), and posterior segment in two weight stages (Group 1: avg.

Dynamics of drug contamination of the river-water in the rural, semirural and urban areas of the Mrežnica River in Croatia during COVID-19 pandemic (2020-2021).

Increased contamination of aquatic ecosystems with pharmaceuticals could have been expected due to the COVID-19 pandemic. Surface water from three domains (rural, semirural, urban) of the Mrežnica River (Croatia) was screened for 253 pharmaceuticals by SPE-UHPLC-MS/MS. At the beginning of the pandemic, the highest concentration of drugs (excluding veterinary) was detected at urban site (291.

Yesterday's contamination-A problem of today? The case study of discontinued historical contamination of the Mrežnica River (Croatia).

The remnants of historical industrial contamination can be detected in many aquatic ecosystems worldwide even at present time. Mrežnica is a river in Croatia that has been, for more than a hundred years, continually exposed to effluents of various industries, which have, in modern time, mostly ceased to operate. Our aim was to establish the level of current contamination and pollution of the Mrežnica river-water and sediments.

Metal-binding biomolecules in the liver of northern pike (Esox lucius Linnaeus, 1758): The first data for the family Esocidae.

Metal-handling strategies of various fish species are known to vary significantly in association with their intracellular metal behaviour. Thus, to better understand the possible consequences of increased metal exposure in fish it is important to perform comparative studies on metal-binding biomolecules in organs of different species. This study was the first of this kind on a liver of an esocid fish (northern pike, Esox lucius), and the gathered information were compared to fish belonging to three other families, Leuciscidae, Cyprinidae and Salmonidae.