widespread use of nanosilver can be led the contamination of aquatic environment and impact on living organisms such as fishes. we investigated histopathological changes in the gills tissue of caspian roach fingerlings after two weeks exposure to sublethal concentrations of nanosilver. following one and two weeks exposure, necrosis, shortening of secondary lamellae, edema, destruction of epithe...

Ž . Circulating plasma cortisol and gill corticosteroid receptors CR have been observed to change seasonally in conjunction with smolting in Atlantic salmon. To differentiate whether these changes Ž . are seasonal or ontogenic, juvenile Atlantic salmon parr were separated by size into upper UM Ž . and lower mode LM in September. At monthly intervals, the fish were sampled for plasma q q Ž . Ž ....

Chemical communication is better understood in freshwater fish than marine fish. The Senegalese sole (Solea senegalensis) is a marine flatfish wherein one of the problems in aquaculture is the poor reproductive performance of hatchery-bred males. Is chemical communication involved in the reproduction of this species? Urine, intestinal fluid and mucus samples were taken from adult fish (wild-cau...

Epitheliocystis, a disease characterised by cytoplasmic bacterial inclusions (cysts) in the gill and less commonly skin epithelial cells, has been reported in many marine and freshwater fish species and may be associated with mortality. Previously, molecular and ultrastructural analyses have exclusively associated members of the Chlamydiae with such inclusions. Here we investigated a population...

Given the identification of new species Johnius taiwanesis, genus in Taiwanese water is here reviewed through a collection field samples, museum specimens, and review scientific literature. Seven valid were successfully identified distinguished based on gill raker length, tip upper jaw to mouth hinge lower length second spine anal fin. Our phylogenetic tree cytochrome oxidase subunit I (COI) sh...

Living in an environment that has been altered considerably by anthropogenic activities, fish are often exposed to a multitude of stressors including heavy metals. Copper ions are quite toxic to fish when concentrations are increased in environmental exposures often resulting in physiological, histological, biochemical and enzymatic alterations in fish, which have a great potential to serve as ...

Myxozoan spores were detected in fecal samples from three patients presenting with abdominal pain and/or diarrhea. The spores were identical to those of Myxobolus plectroplites, a previously described pathogen from the freshwater fish Plectroplites ambiguus. All patients had recently eaten fish caught from local waters, and frozen fillets of such fish were found to be infected with M. plectropl...

1. Introduction A small-sized grass carp (43 cm long) was caught in Lake Whangape, lower Waikato River basin, in May 1997. This fish was too small to be a recapture from the escapement from trial sites in 1984 (fish which are now mostly longer than 70 cm), so could have been either a recent escapee, or the result of natural reproduction in the river. Either way, the finding of this fish indicat...