The housing systems used for snails is called snailery. There are three main systems, namely : extensive or pasture system, semi-intensive system and intensive system. The most important features of any of the systems are that:
1. It’s escape-proof i.e snails cannot escape from the home.
2. It keeps predators out.
3. It allows easy access to tend the snails.
Extensive system priority is the selection of a suitable site, with these characteristics : protection from the wind e.g downhill site with adequate tree cover. The soil should be loamy rich in calcium and organic matter ; not water-logged or acidic.
The temperature must be moderate ( 25-28 degrees Celsius) and the relative humidity must be high ( above 85%).
A large area of between 25sq.m and 50sq.m is fenced round. The fence may be made of chicken wire mesh, wood, bamboo slabs /sandcrete or soilcrete blocks, iron sheets and woven mats.
Devices to prevent the snails from escaping from the tops of fences should be considered when constructing the snailery. The snails are put in the snailery after the food and shelter plants are established. The recommended stocking rate for this system is one mature snail per square meter.
After stocking the snailery, the snails are not provided any care, they will feed only on the leaves and fruits of established plants. They will also depend on rainwater as in the natural habitat. The main advantage of this is that it’s inexpensive to manage because of the low labour and general management inputs.
However, there are disadvantages of this housing system, among which are: the performance of snails is not monitored, there is no control on weeds, predators/parasites and diseases; and much space is required.
The second snail housing system is the semi-intensive which is more like the extensive system except that the snails are supplied with feeds in addition to what’s available in the snailery. Water is also provided.
The third system is the intensive system. Feeds and water are regularly provided for the snails. This system has many advantages, namely: utilisation of small space, there is control over the performance of snails, there is control on predators, and it’s easy to keep records on the performance of the snails. However, it has few disadvantages, which are: high labour and general management inputs, and at least two housing units are required.
A look at the types of intensive housing system shows these:
1. High -fenced Pen 2. Low-fenced Pen 3. Cages 4. Trench Pen 5. Drums 6. Pots 7. Used motor vehicle tyres.
A high- fenced pen is like a room of at least 2 metres high and a low fence is 0.6m (2ft) high. The four walls may be made of any of the following materials/ mosquito netting, soilcrete blocks, sandcrete blocks, planks, metal sheets and bamboo slabs.
Each room or compartment of the low-fenced pen will be 2 meters long, 1 meter wide and 0.6 m high. The lid or roof should be made of mosquito netting reinforced by chicken wire mesh. The dimension of the high-fenced pen is determined by the available space, the roof is made of mosquito netting.
The soil of the pens ( high, low) should be loamy or humus and dug to a depth of 25 -30 cm. If the soil is sandy, clayey or acidic, it should be replaced with loamy or humus soil.
A gutter filled with water is made round the pens to prevent insects and other crawling animals from entering the pens.
Dry leaves of plantain, banana, cocoa or kolanuts are used to cover the soil before introducing the snails into the pens.
Another house is the cage or hutchbox; the cage is like a box and is also called a hutchbox. It may be single or multi-chambered. A single cage is 2 meters long/ 1 meter wide and 60 cm high. It could be made of wood or metal with a lid of wire netting or nylon mesh. The floor is perforated for excess water to drain out. The cage is put on 15-30 cm high stands or sulks which are set in a container of water to prevent ants, termites and other crawling predators from attacking the snails. The cage is filled with loamy or humus soil to a depth of 25-30 cm. Dry leaves of plantain, banana/cocoa or kolanuts are used to cover the soil. A snail hides under the leaves during the day. The cage is good as a breeding, hatchery or nursery pen.
The trench pen is another type of snail pen which is constructed by digging a rectangular trench measuring 2 meters in length and 60 cm deep in the ground. The pen may be single or with many compartments. The side of the trench is built of sandcrete blocks, ano the lid is made of wire netting.
Dry plantain leaves or any plant not injurious to snails are used to cover the soil before introducing the snails. However, the disadvantages of the trench pen are as follows :
The pen is prone to flooding when there are heavy rains; the temperature of the pen may be higher than the desired optimum temperature ( 25-28 degrees Celsius); it provides an inconvenient working posture as one needs to kneel down, stoop or prostrate to care for the snails.
Drums and pots are also a housing system for the snails. Plastic or metallic drums or clay pots may be used to rear snails. The side and bottom of the drum or pot should be perforated for better aeration. The drum or pot is then filled with loamy or humus soil before putting in dry leaves of plantain, banana, cocoa or kolanuts. The snails are then put in the drum or pot that is covered with wire mesh weighed down to prevent the snails from escaping.
Old motor tyres may also be used to rear snails. A tier of three or four tyres is needed when placed on a bare floor while a tier of five tyres is needed on a concrete floor. Loamy or humus soil is the base of both.
If on concrete floor, the first two tyres are filled with loamy or humus soil. Wire or nylon mesh is used to cover the 4 th and 5th tyres, and reinforced with stones to weigh down the wire mesh. Dry leaves of plantain, banana, cocoa, or kolanuts are put on top of the soil before introducing the snails. However, it is necessary to drain water from the ‘free’ tyres frequently at least twice in a week. Tyres are good for hatchlings but not a good breeding house for adults.