PREVALENCE OF DICROCOELIUM-DENDRITICUM INFECTION IN SHEEP IN LEON PROVINCE (NW SPAIN)

A coprological survey was carried out between October 1992 and May 199 3 in the sheep population of Leon province (NW Spain) to estimate the prevalence of Dicrocoelium dendriticum infection. Seven hundred and si xty seven faecal samples from sheep over 1 year of age from 152 random ly selected flocks of the nine Leon province livestock areas (grouped in the four natural regions) were recovered and analysed using a sedim entation method. Results showed a mean individual sample prevalence of 26.7% and a mean flock prevalence of 47.4%. Mixed infections with Fas ciola hepatica were found in 3.7% of animals. The median of D. dendrit icum eggs per gram in faeces was 20 and ranged from 5 to 578. A signif icant association was found between D. dendriticum infection and geogr aphical location with the existence of higher prevalences in northern livestock areas (Mountain region) when compared with other areas in th e province. On the other hand, no significant association between trem atode infection and flock size or anthelmintic programmes used were fo und. Several factors such as climate and poor health and husbandry sys tems are suggested as being related to increasing infection prevalence .