Lamanema chavezi (Nematoda: Molineidae): Epidemiological data of the infection in South American camelids of Northwest Argentina

Faecal samples from llamas (n = 708), vicuñas (n = 171) and guanacos (n = 4) were obtained between December 2004 and May 2009 in three Provinces of Northwest Argentina (Jujuy, Salta and Catamarca) to know the distribution, prevalence and intensity of Lamanema chavezi infection in these South American camelid species (SACs). Faeces were examined by a sedimentation-flotation technique using a Cl2Zn + ClNa solution (specific gravity = 1.59). Eggs of L. chavezi occurred in 30.3% of 89 llama herds and in 18.5% of 708 llamas sampled with a mean intensity of 271.8 eggs/g (EPG) of faeces (range 20–2120). The highest values for all parameters of the infection were registered in llamas from Catamarca Province. Significant differences (P < 0.001, Fisher's exact test) were detected only for the lower prevalence in llamas from Jujuy respect to those from the other two Provinces. The overall individual prevalence of L. chavezi in llamas was lower than in reports from adult domestic camelids of neighbour countries while mean intensity was higher. The individual prevalence of L. chavezi in guanacos was 75.0%, with a mean intensity of 66.0 EPG (range 40–120) while no vicuñas were detected as infected. Most of infected SACs were located at the phytogeographical region of Andean Patagonic Domain with a dispersion ranging between 22°10′ and 26°40′ South latitude.