Abomasal nematodes in goats from the subtropical island of Grand Canary (Spain).

The prevalence of gastric nematodes in 151 goats on Grand Canary Island is around 56%, with a mean burden of 691 worms/animal. No significant differences of prevalence and intensity were found between the four isoclimatic areas of the island [dry-desert (DD); dry-steppe (DS); temperate-mild (TM); temperate-cold (TC)]. Five nematode species were identified, the most commonly-occurring being Teladorsagia circumcincta (observed in 65.8% of parasitized animals) and Trichostrongylus axei (51.9%). The distribution of the two species showed opposing trends: T circumcincta was more prevalent in the coastal areas (DD), diminishing in frequency closer to the centre of the island (TC), while the reverse was true of T axei. The other species identified were Haemonchus contortus, T trifurcata and Camelostrongylus mentulatus; their ranges were restricted to certain areas (H contortus in DS and TM; T trifurcata in DD, DS and TM; and C mentulatus in DD). To analyse the parasite association under natural conditions of an unusual nematode in goats, C mentulatus, with the usual parasites a principal component analysis (PCA) was used to assess the overall behaviour of the nematode community and to examine the Euclidean distances of the parasite associations. The mean Euclidean distances obtained for C mentulatus showed a tendency to a positive association which has also been observed for the other abomasal nematodes.