Snails belong to a group ofinvertebrate animals known as molluscs. Most molluscs carry a shell. Othermembers of this group include slugs, mussels, squid and cuttlefish.
This Agrodok concentrates onthe farming potential of the giant African land snails (GALS), morespecifically the species Achatina achatina, Achatina fulica and Archachatinamarginata. These belong to the family Achatinidae, a diverse group of largepulmonate land snails, originally from western, eastern, and southern Africa,with long slen-der shells. Their size ranges from 3 cm to 25 cm.
The14 genera are:
Achatina, Archachatina,Atopochochlis, Bequeartina, Burtoa, Columna, Callistpepla, Lignus,Limicollaria, Limicolariopsis, Lissachatina, Metachatina, Periderriopsis andPseudachati. They mostly live in jungles in tropical countries, but some maylive in grassland. They primarily feed on fruits and leaves.
They are easy to find and notdifficult to rear. They lay several batches of eggs each year. Generally, theyare quite easy to care for, being able to put up with a range of conditions.
Essentially, a snail consists of two parts, the body and the shell. The body is divided into three parts – the head, the foot and the visceral mass. The head is not well demarcated and carries two pairs of retract-able tentacles.
One pair of tentacles is farlonger than the other and contains the eyes in the knobbed end. The long,muscular foot occupies almost the entire ventral surface and, like the head, isnot clearly demarcated from the rest of the body.
A shallow longitudinal grooveruns along the center of the foot. The hump-shaped visceral mass is housed inthe shell above the foot. It contains the digestive, reproductive, andrespiratory organs.
The skin over the visceral humpsecretes a large calcareous shell (98% of the shell is made up of calciumcarbonate). In most species the shell accounts for about a third of the bodyweight. It is the snail’s protective casing. Whenever danger threatens, thesnail withdraws its body into the shell.