Suitability of six lymnaeid snails for infection with Fasciola hepatica.

The suitability of Fossaria (Bakerilymnaea) cubensis and Pseudosuccinea columella from Louisiana as intermediate hosts for Fasciola hepatica was compared to P. columella and Stagnicola elodes from Ann Arbor, MI, S. attenuata from Hidalgo, Mexico, Lymnaea gedrosiana from Iran and L. natalensis from Senegal. P. columella from LA was shown to be a more suitable host (51.3% became infected) than F. (B.) cubensis (15.2% and 26.4% of two populations became infected). The infection rate for P. columella from MI, was 50% and for L. gedrosiana was 32.5%, whereas L. natalensis, S. elodes and S. attenuata were refractory. F. (B.) cubensis and P. columella have some degree of suitability as intermediate hosts for F. hepatica under laboratory conditions, but field observations of their habitat in southern LA and characteristic management of cattle indicate that the former snail is more important as an intermediate host in this enzootic area. Tissue sections of suitable snails had few histopathological effects but physical damage caused by rediae was pronounced, mainly in the digestive gland and in the mantle.