Circadian variation in locomotor and feeding periods of two land snail species

Feed preferences and feeding behaviour of two species of African giant land snails

“…For A. achatina snails, the highest numbers of feeding snails were observed at 22:30 and 23:30 h (3.59 and 3.54 snails, respectively) which represent the observed periods of peak feeding behaviour in this species while for A. marginata snails, it occurred at 21:30 h (table IV). Ademolu et al (2011) had reported that most feeding activity in the same snail species occurred between 21:00 and 02:00 h. The significantly higher numbers of feeding A. marginata snails (compared to A. achatina snails) at most time periods (figure 2) correspond to the greater distribution of this species to most of the feed stuffs. The highest differences occurred at the periods of highest feeding activity for A. marginata (i.e., 20:30 to 21:30 h) probably due to higher feeding propensity of this species.…”

“…This was to enable each snail reach all the feeds in the shortest possible time. A. achatina and A. marginata snails cover a distance of about 28 cm/h (range: 21.5-34.6 cm, Ademolu et al, 2011) during the active period (nocturnal period). Therefore, the snails were allowed 60 min (1 h) from the time of introduction of feed materials (18:30 h) to sample and settle for the feed of their choice before recording was started.…”

“…The distribution of A. achatina and A. marginata snails in natural habitats is seasonal and the normal activities of the snails such as feeding and reproduction are regulated by seasonal factors and diurnal photoperiods (Albuquerque et al, 2008). The snails are mostly active at night and hide during the day (Ademolu et al, 2011). Snails are polyphagous (Chevalier et al, 2000).…”

“…Snails are polyphagous (Chevalier et al, 2000). They feed on a variety of plant materials (leaves and fruits) as well as on decaying organic matter (Albuquerque et al, 2008;Ademolu et al, 2011). The versatile taste of land snails is an important adaptive feature in the wild however, for rapid growth and high returns in farmed species, adequate nutrition is very important.…”

Comparative Study of the Feeding Characteristics and Digestion Physiology of Haliotis discus hannai and Haliotis gigantea

“…The feeding rhythms of H. discus hannai and H. gigantea are similar to those of Archachatina marginata and Achatina achatina, which are herbivorous terrestrial gastropods. In a previous study, Ademolu et al (2011) investigated A. marginata and A. achatina in an artificial ecosystem and found that their feeding activities mostly occurred during 21:00-02:00 h at night and reached a peak at 00:00 h, whereas both species barely fed during 04:00-20:00 h, and thus both are typical nocturnal animals. Similarly, other herbivorous gastropods (e.g., Turbo chrysostomus and Cerithium tenellum) feed actively at night (Klumpp and Pulfrich, 1989;Klumpp et al, 1992), possibly because of evolution under predation stress (Hahn, 1989) and to avoid competition with herbivores that feed during the day.…”