0000000000868754
AUTHOR
Francesc Padrós
Microbial and histopathological study of the vibriosis caused by Vibrio vulnificus serovar E in eels: The metalloprotease Vvp is not an essential lesional factor
Vibrio vulnificus biotype 2 serovar E (Bt2-serE) is a zoonotic pathogen that causes a haemorrhagic septicaemia in eels, called warm water vibriosis. The main objective of the present work was to study the onset of the eel vibriosis from the microbiological and histopathological viewpoint, as well as to ascertain the role of the protease Vvp as a lesional factor by comparing the histopathological lesions caused by the wild strain and its vvp deficient derivative. The wild-type strain was observed to attach to the gills, where it multiplied following saturation dynamics, subsequently invading the blood stream and reaching the internal organs. Here it reached population sizes that are notably …
Annual variation of parasite communities of deep-sea macrourid fishes from the western Mediterranean Sea and their relationship with fish diet and histopathological alterations
16 pages, 8 figures, 8 tables
MARTX ofVibrio vulnificusbiotype 2 is a virulence and survival factor
Vibrio vulnificus biotype 2 is a polyphyletic group whose virulence for fish relies on a plasmid. This plasmid contains an rtxA gene duplicated in the small chromosome that encodes a MARTX (Multifunctional, Autoprocessing Repeats-in-Toxin) unique within the species in domain structure (MARTX type III). To discover the role of this toxin in the fitness of this biotype in the fish-farming environment, single- and double-knockout mutants were isolated from a zoonotic strain and analysed in a series of in vivo and in vitro experiments with eel, fish cell lines and amoebae isolated from gills. Mice, murine and human cell lines were also assayed for comparative purposes. The results suggest that …
Effects of the gill parasite Zeuxapta seriolae (Monogenea: Heteraxinidae) on the amberjack Seriola dumerili Risso (Teleostei: Carangidae)
Zeuxapta seriolae (Monogenea: Heteraxinidae) infection was associated with important mortalities of amberjacks (Seriola dumerili) reared in tanks in the experimental facilities of the Spanish Institute of Oceanography (Western Mediterranean) during the period 1998–2000. Fish infested by this parasite presented characteristics similar to those described for Seriola quinqueradiata parasitized by Heteraxine heterocerca in Japan. All dead amberjacks had high parasite abundance (mean abundance±S.D.=686.7±125.4) and egg strings entangled in gills. The parasitological analysis of 17 live amberjacks collected from the infested tanks showed that 41.2% of fish harboured Z. seriolae with intensities r…
MARTX of Vibrio vulnificus biotype 2 is a virulence and survival factor
Vibrio vulnificus biotype 2 is a polyphyletic group whose virulence for fish relies on a plasmid. This plasmid contains an rtxA gene duplicated in the small chromosome that encodes a MARTX (Multifunctional, Autoprocessing Repeats-in-Toxin) unique within the species in domain structure (MARTX type III). To discover the role of this toxin in the fitness of this biotype in the fish-farming environment, single- and double-knockout mutants were isolated from a zoonotic strain and analysed in a series of in vivo and in vitro experiments with eel, fish cell lines and amoebae isolated from gills. Mice, murine and human cell lines were also assayed for comparative purposes. The results suggest that …
Accacoelium contortum (Trematoda: Accacoeliidae) a trematode living as a monogenean: morphological and pathological implications
Background Accacoelium contortum (Rudolphi, 1819) Monticelli, 1893 is a frequent but poorly known trematode found on gills, pharynx and digestive tract of the ocean sunfish Mola mola (L.). Although the morphology of A. contortum agrees with that of a typical endoparasitic trematode, with two relatively small suckers and no large holdfasts, this parasite is normally ectoparasitic. The main objective of this paper is to explore this peculiar host-parasite relationship. Methods A total of 106 ocean sunfish were examined for the presence of A. contortum. The oropharyngeal chamber (gills and pharynx) and the digestive tract were analysed. As the previous descriptions of this species seem to be b…
Comparative study of the three attachment mechanisms of diplectanid monogeneans
Abstract One of the main characteristics of the monogenean family Diplectanidae Monticelli, 1903 is their complex haptor formed by 2 pairs of hooks, transversal bars, 14 peripheral marginal hooks, and accessory adhesive organ (lamellodisc or squamodisc) that can be present or absent. Sub-family Lamellodiscinae Oliver, 1969 presents one or two lamellodiscs, formed by several overlapped lamellar esclerites (lamellae) which are piled up. Species like Furnestina echeneis only have one large ventral lamellodisc. This organ function has been categorized in different ways (i.e. accessory adhesive organ, supplementary or compensating disc or sucker), although its real mode of operation and function…