Variations in growth patterns and conformation of snails: influence of strain and location on isometry of growth in cross river state of Nigeria
One thousand four hundred snails of the Archachatina marginata saturalis (Swainson) strain were obtained from two locations each in the three agro-ecological zones of Cross River State. The snails were grouped into various body ranges, namely: small (1 – 50 g), medium (51 – 100 g), large (101 – 200 g) and extra large (201 – 250 g) to evaluate variations in body components and body weights. The mean body weights for small sized snails ranged from 30.71±0.97 g to 40.32±3.31 g. The medium sized snails mean body weights ranged from 67.33±1.28 g to 77.39±2.13 g. The mean body weights for the large and extra large snails varied from 107.26±2.25 g to 125.82±2.58 g and 166.25±2.85 g to 199.37±3.25 g respectively. There were significant differences (P<0.05) for mean body weights among the study locations and different snail sizes studied. The coefficient of variability (CV %) for the body weights of the snails for all the study locations were relatively low, indicating that there were little or no variations among body weights of snails gathered within the study locations. There were relative differences in mean body components (shell length and circumference, mouth length and width, and number of whorls) in all the study locations as well as for the different snail sizes. However, no significant differences (P>0.05) were observed for all these body components within the locations and the different snail sizes studied. The CV % for all the body components measured was relatively very low, indicating little or no variation in the parameters. Nevertheless, rural/local farmers are encouraged to gather only sexually matured snails for consumption and sales.
Key words: Variations, growth patterns, conformation, snails and location.