Life-cycle of Amblyomma oblongoguttatum (Acari: Ixodidae) under laboratory conditions.

This study evaluated for the first time the life cycle of Amblyomma oblongoguttatum in the laboratory. For this purpose, larvae and nymphs were exposed to Gallus gallus (chicks), Rattus norvegicus (wistar rat), Calomys callosus (vesper mouse), Oryctolagus cuniculus (domestic rabbit), Cavia porcellus (guinea pig), and Didelphis albiventris (white-eared opossum). Nymphs were exposed to G. gallus, C. callosus, C. porcellus, O. cuniculus, R. norvegicus, and Nectomys squamipes (water rat). Adult ticks were exposed to domestic dogs. The life-cycle of A. oblongoguttatum in the laboratory could be completed in an average period of 188 days, considering prefeeding periods of 25 days for each of the parasitic stages. Under laboratory conditions, none of the host species was highly suitable for A. oblongoguttatum larvae, since the recovery rates of engorged larvae were always <15%, or most of the times ≤5%. Similar results were obtained for nymphs, with recovery rates of engorged nymphs always <6%. Our results, coupled with literature data, suggest that small mammals, especially small rodents, do not have an important role in the life-cycle of A. oblongoguttatum under field conditions. Domestic dogs showed to be highly suitable for the adult stage of A. oblongoguttatum, in agreement with literature data that have appointed dogs as important hosts for the adult stage of A. oblongoguttatum in South America.