Gills from Atlantic salmon with experimentally induced amoebic gill disease (Neoparamoeba spp.) were examined with transmission electron microscopy to assess pathology and host-cell responses. Amoebae were found either on the surface epithelium or with pseudopodia extending deeply into invaginations...

The effect of exposing Atlantic salmon Salmo salar to hydrogen peroxide was investigated to identify the acute and chronic effects of a single high dose on physiological measurements of stress. A total of 120 Atlantic salmon were divided into 3 groups, exposed to either saltwater (control), or 1000 ...

A new species of trichosomoidid nematode, Huffinanela canadensis n. sp., is described from the skin of rockfish (Sebastes spp.) from the Pacific Ocean off the coast of Vancouver Island (Clayoquot Sound region), British Columbia, Canada, on the basis of the morphology of the adult worms and their egg...

An immunofluorescent antibody test (IFAT) developed for the diagnosis for plasmacytoid leukemia was evaluated against histology under field conditions. Previously published results from a laboratory evaluation indicated that the IFAT had a much higher sensitivity than did histology. One hundred seve...

Studies on the microanatomy of the mucus-rich biofilm surface of normal or damaged teleost skin tissue have been limited because conventional fixation regimes do not effectively retain mucus during tissue preparation. A non-aqueous fixation method, based on a technique devised to retain airway mucou...

This study compared and contrasted the fate of the microsporidian Loma salmonae, a branchial pathogen of salmonids of the genus Oncorhynchus, upon exposure of (1) naive susceptible rainbow trout (RT) O. mykiss, (2) naive RT passively immunized with sera from RT previously exposed to L. salmonae, (3)...

Three exposure studies were conducted to assess whether oral exposure of naive rainbow trout to Loma salmonae spores at 2 temperatures (10 and 14.5 degrees C) provides protection against disease upon rechallenge with spores; to repeat the study at 14.5 degrees C using fish which had recovered from e...

Whitish, opaque, coalescing masses were observed coating the visceral organs of numerous adult coho salmon when they were dissected for artificial spawning in the autumn of 1983 at the Puntledge River hatchery, British Columbia. One affected fish was observed in November 1991. Histological examinati...

The intracellular microsporidian parasite Loma salmonae affects salmonids of the genus Oncorhynchus and is a significant cause of economic losses in pen-reared Chinook salmon (O. tshawytscha) in British Columbia. Loma salmonae infection is easily recognized by the xenomas that form in the gills, but...

In contrast to mammalian therapeutics, the use of pharmaceutical substances is rather limited in fish. It is basically restricted to anaesthetic agents and anti-infective agents for parasitic and microbial diseases. Anaesthetic agents are used primarily in fish farm and laboratory settings to provid...

Lepeophtheirus salmonis is capable of causing severe damage to Atlantic salmon and this study was conducted to examine the physiological response of salmon to the stress of sea lice infestation. Smoltified salmon were acclimatized in 30% saltwater and exposed to high levels of lice infestation. The ...

The presence of dendritic cells in fish is studied with immunohistochemistry using a commercially available antibody developed against Langerin/CD207 present in human Langerhans cells. Langerin/CD207, a protein known to be associated with the development of Birbeck granules in human and murine syste...

Immune response to fish microsporidia is still unknown and there are current research trying to elucidate the events involved in the immune response to this parasite. There is evidence suggesting the role of innate immune response and it is clear that adaptive immunity plays an essential part for el...

Pond-reared channel catfish Ictalurus punctatus with proliferative gill disease (PGD), caused by the myxozoan parasite Henneguya spp., were examined with light and transmission electron microscopy to better characterize the inflammatory response during infection. The early stages of disease are char...

Infection of rainbow smelt Osmerus mordax with the microsporidian Glugea hertwigi was diagnosed for the first time in Prince Edward Island, Canada. The prevalence of infection was 24%, 45 infected out of 187 examined fish captured in February and March 2009. Both large and small xenomas of G. hertwi...

We studied the morphology and occurrence of splenic Langerhans-like (LL) cells in species representing 11 orders of ray-finned fishes, Actinopterygii. LL cells were frequent in spleen tissue of species among Cypriniformes, Esociformes, Salmoniformes, and Pleuronectiformes. These cells contained gran...

Two distinct monoclonal antibodies (MAB) were prepared for testing with kidney, spleen, and retrobulbar tissue imprints made from chinook salmon (Oncorhynchus tshawytscha) affected with plasmacytoid leukemia. (PL). Hybridomas were prepared from mice immunized with whole and lysed cells purified from...

Physiological, immunological and biochemical parameters of blood and mucus, as well as skin histology, were compared in 3 salmonid species (rainbow trout Oncorhynchus mykiss, Atlantic salmon Salmo salar and coho salmon O. kisutch) following experimental infection with sea lice Lepeophtheirus salmoni...

Loma salmonae is an intracellular obligate parasite of farmed chinook salmon (Oncorhynchus tshawtscha) and is the causative agent for microsporidial gill disease (MGD). The infection occurs mainly in secondary gill lamellae, with the formation of large white spore-laden xenomas within the endothelia...

Cytokine genes in fish -- Environmental effects on the ontogeny of non-specific and specific defenses in turbot larvae -- Antibacterial proteins in skin mucus from rainbow trout -- Interferon-induced genes in the rainbow trout -- IPN recombinant vaccines -- DNA vaccination during low temperature and...