Ponderal development of snails, Helix aspersa maxima (gros gris) and Achatina fulica (African giant), fed with different kinds of vegetables

Abstract

This study was conducted to evaluate the ponderal development of Helix aspersa maxima and Achatina fulica escargots in confined conditions and fed an intensive diet with different kinds of vegetables until adulthood. One-month-old juvenile snails from Heliário Modelo of the Centro de Pesquisa em Aqüicultura were fed 30 different kinds of vegetables: sliced green Italian pumpkins with peel (T1), lettuce leaves (T2), "almeirão" leaves (T3), banana peels (T4), banana pulp (T5), eggplants [aubergines] (T6), beet leaves (T7), grated beet (T8), carrot leaves (T9), grated carrots (T10), grated chayote with peel (T11), chayote leaves (T12), butter kale leaves (T13), "escarola" leaves (T14), grated cucumber with peel (T15), radish leaves (T16), green cabbage leaves (T17), purple cabbage leaves (T18), "rucula" leaves (T19), tomatoes (T20), cooked rice (T21), raw and ground green corn (T22), pumpkins (T23), apples (T24), pears (T25), potatoes (T26), pre-cooked rice (T27), cooked ground maize (T28), "brocolos" leaves (T29) and cooked beans (T30). Liveweight (W) and body length (Lch) gains were evaluated weekly. Food conversion was calculated through the relation between the weight of the vegetables offered and the weight of the leftovers. Tukey's test revealed that the best results for H. aspersa maxima were obtained by feeding cooked rice, green Italian pumpkin, purple cabbage and cucumber while the best performance for A. fulica were obtained by feeding cooked ground maize (with water), raw potato, radish and banana peel. Animals fed a unique kind of vegetable did not reach commercial size and preferred soft and humid vegetables. Consumption varied with the type of vegetable used as food and was related to animal size. Snail culture which does not implement a rotational vegetable feeding system will reduce production with individuals showing soft shells and low liveweights.