Integrated rearing system proposal for Cantareus aspersus in experimental orchards: Growth models

An integrated rearing system for Cantareus aspersus under environmental conditions in an experimental orchard is proposed. In this study, the natural behaviour, circadian rhythms and suitable rearing conditions of the edible snail were optimised to produce homogeneous growth and low variability. The growth was standardised, and growth pattern fit was assessed with various models. One thousand fry were cultured in the orchard, and a random sample of 100 snails were measured weekly for 23 weeks. The rearing system had the following characteristics: snails and earthworms were included in the experimental rearing orchard; a homogeneous group of juvenile snails of the same age and size and high rearing density (500 snails/m2) was used; snails were fed with layers mash ad libitum; and mixed and fringes vegetation was planted in the orchard. A commercial size of 60% of snails was achieved in 21 weeks and 95% in 23 weeks. The different models showed a good fit, and the quadratic model obtained the best fit. This experimental snail orchard proposal can be extended to other areas, although it must be corrected according to different environmental conditions and fit to other species of interest. This experimental model could constitute a viable alternative to traditional models of animal experimentation with mammals, and given its high adaptability, it could be applied in different fields of science.

An 112 Days Experiment on Dietary Cadmium Retention in Hepatopancreas in Adult Cantareus aspersus Snails

Cadmium is very hazardous pollutant with massive impact on aspects of everyday life. Little knowledge exists on kinetics of dietary cadmium retention in Cantareus aspersus for durations above three months although this species of land snails serves as excellent ecotoxicological model for studying cadmium hazard. Here was used a continuous 112-day exposure study design, in which test snails were exposed to a wide range of dietary cadmium levels, including human- and environmentally-relevant levels. Using Flame Atomic Absorption Spectrometry, cadmium levels in the hepatopancreas were found to increase significantly, and in dose-dependent manner starting from a dietary cadmium dose of 0.2 mg/kg dry weight. The results of the present study render the hepatopancreas of mature snails, C. aspersus, as excellent endpoints for assessing Cd toxicity over a broad range of concentrations. Hence, this species of land snails can be reliably used for both active and passive biomonitoring of environmental cadmium pollution.