CONICET | Buscador de Institutos y Recursos Humanos

Lymnaea columella is the main intermediate host of Fasciola hepatica in Northeastern Argentina. The knowledge of its biology is essential for the development of effective measures to control fasciolosis. The aim of this work is to study the survival, mortality rate, fertility and fecundity of L. columella under laboratory conditions. The ultimate goal is to develop an efficiently rearing system with many reproducing adults and a continuous production of offsprings that could be used in future biological assays. In total, 1206 L. columella snails were collected in the locality of Berón de Astrada, Corrientes Province, Argentina and transported alive. In the laboratory, they were placed in groups of 30 individuals in glass aquaria with filter and aerated water, maintained at 22ºC and under a 12:12 light:dark photoperiod. They were feed with fresh lettuce ad libitum and pieces of Styrofoam were added as oviposition sites. Every 3 days water was changed, fresh lettuce were added, dead snails and unconsumed lettuce were removed and the number of living snails was registered in all recipients The number of egg capsules and their date of hatching were registered weekly. Wild L. columella survived under laboratory conditions for 231 days (8 months). The monthly mortality rate ranged between 25.9% in the 2nd month and 69.5% in the 8th month, with a mean of 53.3% ±0.2. During this period, L. columella snails laid a total of 4.198 egg capsules, with an average number of 12.6 eggs each (Min= 4; Max= 30 eggs). The fecundity (# of egg capsules/adult) ranged between 0.2 and 1.6 (Mean= 0.7; SD= 0.4). The mean fertility rate (% of hatching eggs) was of 57.1%. Our results show that L. columella can be successfully reared under controlled conditions. Snails rapidly adapt to laboratory conditions and start to reproduce immediately.