Archachatina marginata swaison (African Giant Siam) is one of the important minor forest products which is endemic in tropical West African (Swaninson, 1991). It is restricted to areas like Benin republic in West Africa (Bequeert, 1950 and Moad, 1950). Omole (2000) asserted that archachatina margniata is the largest snail in Africa.
            Literature review on the body weight of snails has remained inconsistent   (Ebenebe  et al., 2011). Omole, (2002) reported a body weight gain of Hamzet et al (2005) reported a mean daily weight gain of 1.16g while Ejidike (2000) reported 0.50g in a six months study period.

            The inconsistency agrees with Stievenart (1992) that prove that variation in body weight on snails are related to the hydration stage, stoutness and shall the heaviness live thickness of calcium deposit during the process of shell calcification.
            Archachatina marginata is economically important because the species is in high demand as a protein source in many West Africa countries including Nigeria (Ajayi et al., 1978), where the meat is a luxury food.
            Despite the importance of the species, archachatina marginata is not cultivated on a commercial level and as a result of human-related problems like deforestation and its collection for food and its long pre-reproduction life and low fecundity (Ajaysi et al., 1978 and Egonmwan, 2004), the natural population in the wild is dwindling.
            However,  in recent years, the commercial potential  of the species  being  investigated  by  many amateur snail farmers and more attention is being paid  to farming of the giant  snail as  opposed  to exploitation of  the wild  population. In Nigeria, snails have been raised in small pens in many areas either as backyard activity to supplement house hold income and protein supply or as large scale commercial activity. 

Snails like other animals need the basic nutrients (energy, protein, fats, amino-acid, vitamins and mineral for optimum functioning of metabolic chemical reactions involved in growth maintenance, shell formation, production and reproduction (Imevbore and Ademosun, 1988). The choice of feeding materials are based on available information that snails are vegetarians (FAO, 1986 and Philips, 1992) to the extent to which each of the feeding materials can influence the growth rate of snails. Snails’ requirements for calcium, phosphorus, potassium and magnesium are relatively high compared to other animals. These minerals determine the rate of shell secretion by the mantle and for the rapid development of shell (Imevbore and Ademosun, 1988). Vitamins can not be synthesized by snails so must be provided in the diets (Imevbore and Ademosun, 1988)

2.2.1 Crude Protein
Snails require crude protein like other speices of animals for growth and production. According to Ejidike (2001) snails, require crude protein leaves of 20-25% for optimal growth.

2.2.2 Energy Requirement
Metabolisable energy requirement for maintenance of animals is affected by ambient temperature (Balnave and Farrel, 1978), snail should therefore eat more high energy ration.

The potential of snails as an animal protein source has been emphasized by many authors (Nigbert, 1974; Jennifer, 1975; Datin, 1992; Hamzat et al., 2005; Adetono, 2000; Awah, 2000; Ejidike 2001; Omole, 2002).
Snails have been reported to be rich in protein, 12-18% on wet basis (Awah, 2000) and 52- 53% on dry matter basis (Barcelo, 1981). Snail meat is also low in fat and it is reported to have some medical properties (Aweh, 2000).
Many feasibility tests have been down on snails as a source of nutrition (protein) in developing countries like Nigeria. Researchers baked snails’ pies and give them to young mothers and children living in Nigeria, to their surprise, most of the children as well as their mothers preferred the tests and texture of the snail pie over that of beef pie. This is good news since snails are readily available source of nutrition that can be easily collected and prepared as food. No farmland is required to raise them and large pool of labour is not needed to collect them and turn them into meals.
Considering this question. Is eating snail nutritious? Snails are surprisingly nutritious. High in protein and very low in saturated fat. One ounce of snail has five grams of protein and is an excellent source of essential fatty acids. They are also a good source of vitamin E, Vitamin D, Vitamin B12, Vitamin K, magnesium, iron, and selenium.
Ajayi (1978) indicated that snail meat is particularly rich in protein and iron. Bender (1992) reported that the amino acids in the protein of snail would complement the cereal source of protein by making good of their relative deficiency of lysine. The low fat content and low cholesterol level make snail meat a good antidote for vascular disease such as heart attack cardiac arrest, hypertension and stroke.

Environment is the combination of external physical conditions that affect and influence the growth, development and survival of organisms. Snail farming can be indoor or outdoor provided environmental conditions necessary for survival following environmental factors are ideal.

2.4.1   Temperature: Temperature influences the activities of snails such that the temperature   above 200C will cause the snails to stivate or hibernate in order to regulate the body fluid.  Sails thrive well under ambient temperature of 200C with considerable growth rate all year round with zero chance of aestivation. Temperature and humidity of 80 hand in hand are very critical in the survival of snails.
2.4.2   Humidity:     Humidity is a very critical factor to snails as they have to maintain a constant equilibrium between fluids.  A humid environment is required for snails to remain active and bred all year round. It is therefore, necessary to moisten the environment during dry periods. Humidity and water availability are very important in snail rearing and influence feeding.  During dark hours, air   humidity of 80% will promote  good snail activity  and growth through snails need water but their environment must not be water logged.

2.4.3   Light
            Snails naturally require light for optimal growth. Lighting can be achieved by   natural and artificial means. At the level of our technological advancement, natural lightening is mostly employed. Light essentially is necessary for some biological process such as photosynthesis which is very vital in energy cycle in food chain. Intensive snail production involves artificial lighting system to prompt the snails into their natural reproductive cycle. Three environmental factors (daylight, temperature and humidity) influences the reproductive   cycle of snails (Yusuf, 2002).  Research  has  shown  the exposure   of  snails  to continuous  light  increased their  activity  and rate  of food consumption and thus promote  their  rapid growth  (Akinusi, 2002).
2.4.4   Soil:    Soil is a m medium for reproduction of snails.  Good management practice involves   selection and mixture of soil.  It should be  recalled that soil harbours   a lot  of  pests and  predators,  and so should be properly  analyzed  before using  it  in  snail activities.  A mixture of sand  and  clay in a good  proportion retains water and therefore  not suitable because  during  raining season  it  becomes water logged  and cakes up during dry season  which makes it too hard  for snails to burrow through. Loamy soil is recommended as it contains enough organic matter with good retentive capacity. Acidic soils should be avoided. If   an acid   soil cannot be avoided, lining is encouraged. Periodic application of calcium is also encouraged where and when it is absent. The soil should not contain harmful sails or be so alkaline so as not to burn the snails (Akinnusi, 2002).

            Snails are known to escape from enclosures that are not properly protected or covered. It therefore becomes imperative that snail houses should be protected to prevent the snails from escaping and be predator free.
            The housing for raising snails varies with purpose. However, it could be made of wooden materials, wire mesh or even local materials whether outdoor or indoor. Depending on the size of the farm, cages or hitch boxes, trench pens, used types local baskets, movable pens and mini paddock are used to prevent snails from escaping. The cage should not be exposed to direct sunlight as this can raise the temperature of the enclosed container to injurious levels. However, they should be exposed to normal day/might cycle (Akinnusi, 2002) where cage boxes are used the cover should be meshed to acid spraying of water without having to open the box. No matter the type of housing, the habitat of snails must be taken into shade as snails like hiding places. When snails are raised indoors under controlled environmental factors favouring production must be provided. The housing must be  provided with devices for measuring  humidity (hygrometer), temperature  (thermometer), soil moisture and light (in-foot candles) weighing  balance, soil testing  kit, magnifying  glass and  watering cans.
2.5.1 Housing System
There are three main housing system for rearing snails namely extensive, semi -intensive and intensive system.
Extensive system: This type of system is essentially practical in the open parks/gardens. The snails are reared in their natural habitat except  that choice plants are planted and park or fenced gardens are provided to avoid the escaping of the snails.
Semi intensive system: This system combines both indoor and outdoor practices. The reproductive and nursery stages raised indoors while the growing period are outdoors.  This system  enable the farmer to grow and produce snails all year round making them available to numerous consumers.
Intensive system: As the name implies, the system requires a high capital investment with modification of the environment to stimulate what happens naturally during the park period to ensure optimum reproduction and growth. This system ensures all year production of snail and regular supply on demands.
2.5.2 Pest and Diseases
            The natural enemies/ predators of snails are members of many vertebrate groups such as beetles, cricket, centipedes, snakes, toads, turtles and birds. Human also impose very serious threat to snails through pollution and destruction of natural habitats of snails which have led to extinction of a number of species. Cannibalism among hatching (first snails that hatch) is also common. These young snails gather up the shells of their eggs which give them the much needed calcium for building their own shells, after which they may begin to eat the unhatched eggs.
            Parasites nematodes,  trematodes, fungi and anthropods may equally attack snails. Such problem occur as a result of over crowding, pseudomonas acruginosa causes intestinal infections that can spread rapidly in over crowded pens farm. Where it attacks egg clutches preventing them from hatching.
Control is not difficult in semi intensive and intensive systems. Once there is infection of fungi, the egg can not be redeemed, all that could be done is to burn and dispose the soil where the eggs are laid (Akinnusi, 2002).

            The urgent need for a high quality feed for animals in the tropics and the excellent characteristics of mulberry are the justification for the great enthusiasm for its intensive cultivation and use or feed supplement for animals and mini livestock like snails.
            The nutritional quality of locally produced mulberry leaves is equivalent to that of grain based concentrates thus, they are an ideal supplement in most forage diets.
            The nutritive value of mulberry leaves becomes greater in inverse proportion to animal size, since metabolic rate and hence nutrient requirements  decrease in size. Mulberry leaves should be the preferred feed for guinea pigs, rabbits, and perhaps snails, (Oviedo et al., 1994) many more excellent results are to be expected when mulberry is offered to other herbivores small species in particular. There is a report of ad libitum dry matter intake of 4.18% of liveweight (average of three lactating goats) which is much higer than in other tree fodders, the dry matter intake of mulberry leaves of 3.44% of the body weight in sheep under experimental conditions.  
            In costa rica, liveweight gains of bulls belonging to the Romosinuano breed (a criollo type) fed elephant grass, increased to over 900g/day when mulberry was offered as a supplement at 1.7% of their body weight on dry matter basis.
            Growing Zebu and Brown Swiss steers being fed increasing levels of mulberry as supplement to a sorghum silage diet, the animals showed good growing rate.
Although the growing rates with the highest mulberry level are not impressive (195g/day) most likely due to poor quality of the silage a combination of mulberry and trichantera gigantea leaves as the protein source and blocks made of molasses, cassava root meal and rice brains as the energy source gives better reproduction and growth performance than a diet of commercial concentrates and grass supplement. In conclusion, mulberry leaves provides enough nutrients for maintenance.

Mulberry plant is a perennial plant, usually cultivated as mono crop for its leaf to rear silk worms majorly (Gunase khar et al., 1998).  The chemical composition of mulberry Leaves has been studied by many authors. The crude protein content in leaves varies from as low as 15% to 28% depending on the variety, age of the leaves and growing conditions. In general, crude protein values can be considered similar to most legume forages. Machii (1989) reported that the protein quality of mulberry leaf is comparable to that of soya bean meal.
            Fibre fractions are low in mulberry leaves compared to other foliages. Shayo (1997) reported lignin (acid detergent lignin) contents of 8. 1% and 7. 1% for leaves and barks respectively. A striking feature of mulberry leaves is the mineral content, with ash values up to 25%. Typical calcium contents are around 1.8-2.4% and phosphorous 0.14-0.24%. Espinoza et al. (1999) found potassium values of 1.90- 2.8% in leaves and 1.33-1.53% in young stems. The essential amino acids are over 46% of the total amino acid in mulberry. The average nitrogen (N) is 16.6% of the total molecular weight of the mulberry amino acids (Plus ammonia). Mulberry leaves contain 1130 kcal -2240kcal of metabolisable energy and absence of anti- nutritional factors (Omar et al., 2006)

            Chromoleana odorata belongs to the family Asteraleae .Its common names are Awolowo, independence weed or siam weed (Okon and Amalu, 2003). It is used as a livestock feed because of its high protein content and less anti-nutritional factor (Iwu, 1993 and Phan et al., 2001) Chromoleana odorata after 4-12 weeks of re-growth showed that the leaf fraction had a crude protein content about 194/kg dry matter (DM) and average leaf of stem ratio of 2: 1: 1. Chemical analysis of the leaf fraction of an 8- week-old regrowth indicated a high crude protein content  of 258 g/kg DM and a high degradable nitrogen content but low in neutral detergent fibre (33l g/kgDM) acid detergent lignin (53 kg/DM), total extractable phenolic (37.1kg/DM) extractable tannin 0.72, absorbance at 550 mm) and extractable condense tannin (1.4 g/kgDM) in sacco degradability analysis of the 8- weeks old regrowth, leaf sample showed a higher 48%  organic matter (935g kg -1DM) and crude protein (953 g/kgDM) degradability the leaf sample has an organic matter degradability of 670 g/kg DM as estimated by cumulative gas production in vitro after 24hrs incubation. There was a little or no phenolic- related anti nutritive factors in chromoleana odorata. Additionally, leaf samples had no effect on rumen protozoa activity. Chromoleana odorata leaves are of high nutritive value and might have the potential to be used as a protein supplement of leaf meal of chromoleana odorata in feeding animals is the presence of anti- nutritional factor (Checke and Myer, 1975) and this probably could be avoided by adopting proper harvesting and sun- drying procedures (Fasuyi et al., 2005)

Chromoleana Odarata has medicinal values and are usually used in treating inflammation and serves as an anti-fungi, anti-hypertensive and anti-fungal agent (Akimoladun et al., 2007).

Information on the use of chromoleana odorata in livestock nutrition is very scanty. This might be as a result of the widespread speculation about of its toxicity to animals and offending nature of its odour. Reports of Madrid (1974) of the consequent death that occurred in cattle following ingestion of Chromoleana odorata leaves attested to the toxic nature of the plant in livestock nutrition are as reviewed below
            Nwokolo (1987) delved edaborately on the mineral and amino acid composition of Chromoleana odorata. He reported on the amino acid composition and availability of these leaf meals (Table 2). He concluded that the values obtained for both mineral and amino –acid availability could be attributed to the presence of anti nutrient factors, especially of tannins since they occur in high concentration in plant materials and are associated with toxicity and poor growth rate and depressed dietary nutrient utilization in livestock animals.
Table 1 Mineral composition (Mg/kg) of C.O leaf meal (dry matter basis)

 Mineral                                 hromoleana odorata leaf meal
Phosphorus                                       4.532
Calcium                                             11,551
Magnessium                                      3202
Potassium                                          13 800
Copper                                               37
Zinc                                                    52
Manganese                                        71
Iron                                                     79

Source: Nwokolo (1987),

Table2: Animo Acide composition of C.O. leaf meal Amino acid
Amino acid                            Chromoleana odorata leaf meal
Asparte acid                                      8.2
Threonin                                            3.5
Serine                                                 3.5
Elutamic acid                                    8.0
Proline                                               4.5
Elycine                                               4.2
Alanine                                              4.4
Cysteine                                             0.8
Valine                                                4.1
Methionine                                        1.3
Isoleucine                                          3.2
Leucin                                                6.4
Tyrosine                                            2.0
Phenylalanine                                   3.7
Histidine                                            3.2
Lysine                                                4.7
Arginine                                             4.
Amino acid availability (%)           65.40
Source: Nwokolo (1987).

Table 3 Dry matter gross energy and proximate composition of Chromoleana odorata leaf meal.
Nutrient                                             Chromoleana odarata leaf meal nutrient
Dry matter (%)                                  87.40
Crude protein (%)                            18.67
Crude fibre (%)                                11.67
Ether extract(%)                               1.01
Ash (%)                                              3.63
Nitrogen free extractive (%)          3.332

Source: Aro (1990)



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