title: Contracaecum sp. infection in Hoplias malabaricus (moncholo) from rivers and marshes of Colombia.
abstract: Nematode infection indices were recorded in Hoplias malabaricus captured in six different rivers and a marsh belonging to the North Coast Basin of Colombia, and from the Amazon River, during February 2003-December 2004. Preliminary morphological analysis of nematodes indicated the presence of Contracaecum sp. Parasites were mostly found in the intestinal mesenteries and a very low percentage in muscle. Parasite prevalence in all sampling locations at the north of Colombia was 100%, whereas in the Amazon River it was 6.12%. The mean intensity in the different stations were as follows: Magdalena River at the City of Magangué (58.92+/-7.59), Magdalena river at the city of Zambrano (128.9+/-7.08), Sinú River (53.88+/-4.92), Dique Channel (207.3+/-59.52), Cauca River (77.26+/-9.35), Atrato River (21.11+/-2.6), San Jorge River (39.5+/-7.13), and Totumo Marsh (62.5+/-6.38). In average, all specimens of Hoplias malabaricus from the north coast basin of Colombia were infected with a mean intensity of 77.82+/-4.81 (1-466 parasites per host) whereas in fish from the Amazon River this value was significantly lower (intensity 1.0+/-0.0). Size and weight correlated significantly with parasite intensity in fish collected from sampling locations at the north of Colombia (R=0.240, P<0.001 and R=0.199, P=0.008, respectively). Moreover, a significant, but low and negative correlation was found between condition factor and parasite intensity (R=-0.159, P=0.034), suggesting a possible impact of parasites on fish health. These results suggest, for the first time, that the parasitism in Moncholo is a widespread phenomenon in Colombian rivers and could represent a risk factor for human consumers.
authors.affiliation: Environmental and Computational Chemistry Group, University of Cartagena, Cartagena, Colombia. jesusolivero@yahoo.com
authors.forename: Jesús
authors.initials: J
authors.lastname: Olivero-Verbel
authors.forename: Rosa
authors.initials: R
authors.lastname: Baldiris-Avila
authors.forename: Jorge
authors.initials: J
authors.lastname: Güette-Fernández
authors.forename: Amparo
authors.initials: A
authors.lastname: Benavides-Alvarez
authors.forename: Jairo
authors.initials: J
authors.lastname: Mercado-Camargo
authors.forename: Barbara
authors.initials: B
authors.lastname: Arroyo-Salgado
mesh_terms: D000818:Animals; D017191:Ascaridida Infections / Q000453:epidemiology / Q000469:parasitology / Q000662:veterinary*; D001199:Ascaridoidea / Q000033:anatomy & histology / Q000254:growth & development / Q000302:isolation & purification*; D001835:Body Weight; D003105:Colombia / Q000453:epidemiology; D003257:Consumer Product Safety; D005393:Fish Diseases / Q000453:epidemiology* / Q000469:parasitology*; D005399:Fishes; D006790:Host-Parasite Interactions; D006801:Humans; D012307:Risk Factors; D045483:Rivers; D017747:Seafood / Q000469:parasitology