engleski

Camallanus sp. infection in cage-reared bluefin tuna (Thunnus thynnus)

Tuna facilities are on growing and expanding in the Mediterranean, even there are still a limited number of studies regarding the health status of cage-reared northern bluefin tuna (Tunnus thynnus). Munday et al. (2003) brought up detailed review of diseases of economically important tuna species, with very long list of isolated pathogens, making any of these agents in the position to become potential threat for tuna culturing. The largest group of reported pathogens consists of parasites, usually acquired during fish migration whose decline in prevalence and abundance however, was noticed during the rearing cycle (unpublished data). During the parasitological survey of newly caught tuna and introduction in cages, a moderate prevalence and abundance of adult nematode Camallanus sp. (Camallanidae: Spiruridae) was observed. Isolated individuals differed greatly from the previously reported Oncophora melanocephala (Camallanidae: Spiruridae) in T. thynnus, T. albacares, T. atlanticus and Auxis thazard, by morphology of the buccal capsule, body coloration and in being viviparous (Moraves et al, 1999). Deep erosions, hemorrhages and lymphocytic infiltration were determinate histologically on the insertion of nematode’ buccal capsule in the pyloric mucosa. Nevertheless great invasivity of the nematode and pathological changes, no mortalities related to the infection were contracted and afterwards surveys did not show the presence of the camallanid again.

camallanus sp. ; bluefin tuna

nije evidentirano