Cormorant pellets as a tool for the knowledge of parasite-intermediate host associations and nematode diversity in the environment

LUCAS E. GARBIN; JULIA I. DIAZ; ANNICK MORGENTHALER ; ANA MILLONES ; LUISA KUBA; DANIELA V FUCHS; GRACIELA T. NAVONE

HELMINTHOLOGIA

VERSITA

Lugar: Varsovia; Año: 2019 vol. 56 p. 296 - 302

0440-6605

Anisakids are usually acquired through the diet. Cormorant pellets are useful to detect both parasitelarval stages, and prey items which could act as intermediate hosts in the environment. The currentstudy provides information about the feeding habits of both birds and mammals, and the diversity ofparasites circulating in the environment. The objective of the study was to identify Anisakidae larvaeand prey items in pellets from the Imperial shag Phalacrocorax atriceps and the Red-legged cormorantP. gaimardi, suggesting possible parasite?prey associations. A total of 92 P. atriceps? and 82 P.gaimardi?s pellets were collected from both Punta León, and Isla Elena bird colonies, respectively,during the period from 2006 to 2010. Pellets were preserved in ethanol and hard prey item remnants,and nematode larvae were studied using standard techniques. Prey item occurrence, nematodeprevalence, and mean intensity were calculated. A correspondence analysis was performedto evaluate the larvae-prey association. Contracaecum spp., Pseudoterranova spp,, Anisakis spp.,Terranova spp., and Hysterothylacium spp. third-stage larvae (L3) were identifi ed in pellets. Pseudoterranovaspp. and Anisakis spp. L3 predominated in the environment of Punta León, whereasContracaecum spp. and Hysterothylacium spp. L3 predominated in the Puerto Deseado area. Thehighest larvae-prey association was that of Contracaecum spp. L3 with Engraulis anchoita, followedby with Odontestes sp. in P. atriceps? pellets. Contracaecum spp. L3 were signifi cantly related toboth sprats, Sprattus fueguensis and Ramnogaster arcuatta, in P. gaimardi?s pellets. It was verifi edthat E. anchovy is the main gateway of Contracaecum spp. L3 in P. atriceps. Odonthestes sp. mightact as an intermediate/paratenic host of Contracaecum spp. L3 in the area. Both sprats might playa role as intermediate/paratenic hosts of C. australe, being the main gateway into P. gaimardi in thearea. Thus, pellet analysis can be postulated as a good tool for indicating parasite-host associationsbetween anisakids, and the prey items which act as intermediate hosts.