RESUMO
The Argentinean short-finned squid (Illex argentinus) is an oceanic, neritic species widely distributed off the east coast of South America, representing the most abundant commercially exploited squid species in these waters. Despite the great commercial importance of Argentinean short-finned squid as a food resource, and as frozen product exported to Europe, the presence of zoonotic anisakid nematodes, especially in the mantle of the squid, is poorly known. The occurrence and site of infection of larval ascaridoid nematodes in 70 I. argentinus caught off the Falkland Islands were investigated. Squids were examined using the UV-Press method. In total, 30 nematodes were detected in the viscera and mantle. According to morphology, 27 were third-stage larvae (L3) belonging to genus Anisakis, while three were L3 assigned to Hysterothylacium. Anisakis pegreffii (nâ¯=â¯27) were identified by sequence analysis of the mtDNA cox2 and the partial EF1 α-1 region of nDNA genes; Hysterothylacium aduncum (Nâ¯=â¯3) were identified by sequence analysis of the ITS rDNA region. These findings represent the first molecular identification of A. pegreffii and H. aduncum in I. argentinus. Both prevalence (Pâ¯=â¯15.7%) and abundance (Aâ¯=â¯0.39) of infection with A. pegreffii were low, and even lower values of infection were recorded for H. aduncum (Pâ¯=â¯2.1%, Aâ¯=â¯0.04). Only 3 out of 70 (4.3%) squids hosted A. pegreffii larvae in the mantle. Larvae infecting viscera were coiled and mainly attached to outer surface of visceral organs. Mantle-infecting larvae were situated in the posterior half. Thus, these results suggest that - although low - the risk of acquiring anisakiasis from consumption of raw, marinated and/or undercooked short-finned squid products still exists.
Assuntos
Anisaquíase/parasitologia , Ascaridoidea/genética , Decapodiformes/parasitologia , Doenças dos Peixes/parasitologia , Parasitologia de Alimentos , Alimentos Marinhos/parasitologia , Animais , Anisaquíase/epidemiologia , Anisakis/genética , Ascaridoidea/classificação , Oceano Atlântico/epidemiologia , DNA Ribossômico/genética , Ilhas Malvinas , Doenças dos Peixes/epidemiologia , LarvaRESUMO
The distribution of franciscana Pontoporia blainvillei Gervais & d'Orbigny, 1884, is restricted to the estuarine and coastal waters of the southwestern Atlantic. The diet of this dolphin is composed of fishes, squids, and shrimps, many of which harbor helminths that may infect franciscana. Larval forms of the trematode Synthesium pontoporiae and the acanthocephalan Bolbosoma turbinella have been recorded in franciscana; however, they have not yet been identified in any of the prey species of this cetacean. We evaluated 3 components of the diet of franciscana as possible transmission sources of parasitiasis. Specimens of São Paulo squid Doryteuthis sanpaulensis (n = 50), banded croaker Paralonchurus brasiliensis (n = 43), and rough scad Trachurus lathami (n = 50) were necropsied. Organs were washed and examined under a stereomicroscope. Helminths were collected and mounted on slides. None of the species analyzed showed infection by metacercariae of S. pontoporiae. Helminths found in São Paulo squid have not been recorded in franciscana. Cistacanths of Corynosoma australe were found in the coelomic cavity and mesentery of croaker (prevalence [P] = 53.49%; mean infection intensity [MII] = 6.74) and scad (P = 4%; MII = 1.50). Cistacanths of B. turbinella were also found in the same sites in scad (P = 14%; MII = 2.14). Banded croaker and rough scad are recorded in this study as new paratenic hosts for C. australe, while scad is a new paratenic host for B. turbinella.