Archachatina marginata

Transcription

1 FOOD AND FEEDING HABIT OF GAINT LAND SNAIL Archachatina marginata BY ABAKWAM, LOVETH ONYINYECHI 12/15073 A PROJECT PRESENTED TO THE DEPARTMENT OF ANIMAL AND ENVIRONMENTAL BIOLOGY, FACULTY OF SCIENCE, IMO STATE UNIVERSITY, OWERRI. IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE AWARD OF BACHELOR OF SCIENCE (BSc.) IN ANIMAL AND ENVIRONMENTAL BIOLOGY. SUPERVISOR: PROFESSOR P.U. OKORIE NOVEMBER,

2 DECLARATION I hereby declare that this study with the write up is my original contribution under supervision of Professor P.U. Okorie to the best of my knowledge this work presented herein has not been submitted in part or full for any other degree of this and any other University Student s name Signature Matric. Number Date 2

3 CERTIFICATION This is to certify that the work embodied in this project titled Food and Feeding Habit in Giant Land Snail Archachatina marginata was carried out by Abakwam Loveth Onyinyechi with the matriculation number 12/15073 under the supervision of Professor P.U. Okorie Student Date Prof. P.U. Okorie Date (Supervisor) 3

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5 DEDICATION This work is dedicated to God almighty for being my inspiration and guardian throughout the period of this work. 5

6 ACKNOWLEDGEMENT I acknowledge the effort of my supervisor, PROF. P.U. OKORIE in making sure that this project was a success. I pray that the Almighty God will reward and bless him abundantly. My sincere gratitude also goes to all the staff of the Department of Animal and Environmental Biology who contributed in one way or the other for the success of this project. I also acknowledge the effort of my dear parents; Mr. & Mrs. Joseph Abakwam, brother: Victor, sisters: Vivian and Nancy. And also my friends: Queeneth, Assumpta, Happiness, Toochukwu, Confidence, Nice and many others, for their encouragement and financial support. 6

7 ABSTRACT An experiment was conducted on the food and feeding habit of African giant land snail (Archachatina marginata). Fruits and local leaves were used as test foods. The snails were separated into three groups according to their weight. The snails fed on almost all the fruits and local leaves presented to them except for the pepper leave, Piper guineese leave and African grape fruit. Thus, among all the fruits and vegetables given to them, pawpaw fruit and pawpaw leaves ranked first (1 st ) in the order of preference. A. marginata from this study did not feed according to their sizes when relating the proportion of food intake to their body weight because the smaller snails having the mean weight of 43g had higher food intake both for the fruits and vegetables than other Groups (Medium size: 100g, Large size: 170g). Mortality was not recorded during the experiment. The food and feeding habit of A. marginata showed that they have a wide range of food spectrum and mostly fed at night and early hours of the morning. 7

8 TABLE OF CONTENTS Title page i Declaration ii Certification iii Approval iv Dedication v Acknowledgement vi Abstract vii Table of contents viii List of Tables xi CHAPTER ONE: INTRODUCTION 1.1 Justification Of Study Aim And Objectives Scope of study Literature review Historic background

9 1.4.2 Scientific classification A. marginata Description of A. marginata Geographic distribution of A.marginata Mating and Egg laying Growth of Snails Food and feeding Pattern of Snails Climatic conditions and soil characteristics Predators, parasites and Diseases of snails Economic importance of A. marginata CHAPTER TWO: MATERIALS AND METHOD 2.1 Location of study Food and their sources Experimental Animals and their sources Experimental method CHAPTER THREE: RESULTS 3.1 Food spectrum Preference

10 3.3 Food intakes as proportion of body weight CHAPTER FOUR: DISCUSSION AND CONCLUSION 4.1 Discussion Conclusion and Recommendation References Appendixes 10

11 LIST OF TABLES Table 1: Experimental snails in relation to their body weight Table 2: Experimental fruits with their botanical name Table 3: Experimental vegetables with their scientific name Table 4: Food items in the descending order of preference for FRUITS--27 Table 5: Food items in the descending order of preference for VEGETABLES Table 6: Food intake as a proportion of body weight for FRUITS Table 7: Food intake as a proportion of body weight for VEGETABLES-30 11

12 CHAPTER ONE 1.0 INTRODUCTION African giant snails serve an increasing important role in the tropics by virtue of their survival under captive rearing, resistance to parasite and diseases, ability to accept and convert plant parts and artificial diet to flesh as well as being of high consumer s preference. In West African, the most predominant giant land snail Species include: Achatina achatina, Achatina fulica and Archachatina marginata. The Archachatina marginata is the most accepted and highly cherished snail specie in Nigeria. However, snail rearing (Heliculture) has become very important in recent time because of increased animal protein shortage in Nigeria. Also, the availability of some edible snails in Nigeria, their popularity and acceptability nationwide, the potential for exports including the emerging technologies of their production have largely contributed towards the present renewed interest in snail farming (Amusan and Omidiji, 1998). Ebenebe (2000) pointed out that it is high time that we looked inward and integrate into our farming system some non-conventional meat source like snails. This will go a long way in reducing the problem of protein 12

13 malnutrition, which is real in most developing countries of the world. These countries are mostly located in the warm humid tropics where the level of animal protein intake represents about one-tenth of the level of intake in the advanced countries (Esonu, 2001). Kehinde et al., (2002) reported that the protein consumption in Nigeria is below 67g recommended by the World Health Organization. Snail farming can conveniently be done in our back yards; this is due to the fact that snail farming is environmentally friendly and can be done with little skill (Akinnusi, 1998; NRC, 1991). The fecal matters neither smell nor make the environment filthy in any way. Snails are also good converter of vegetable protein to useful animal protein (Obi et al. 2001). They provide a very cheap source of high quality animal protein for human consumption. Snail farming is also a high profit-yielding venture and requires little capital when compared to other forms of animal farming. Thousands of land snails can be raised in a small land space if intensively managed and there is always less need for vaccination and therapeutic drugs. Hence, predators, parasites and diseases can easily be prevented through proper housing, management and sanitation. 13

14 Rebecca and Sheldon (2004) reported that snail production has gone to an advanced stage in American, Europe and Asia but in Africa, much research work has not been carried out. In West African, Archachatina marginata of Nigeria and Achatina achatina, produces the largest number of egg of about eggs per clutch. Other snails of African origin produce less number of eggs of between 5-15 eggs per clutch. Achatina achatina is also known to be the tropical species of snail that is most accepted in the World (Amusan and Omidiji, 1998). Snail meat favorably competes with poultry egg and flesh in essential amino acids and digestible proteins (Imevbore, 1990). It is essentially rich in lysine, leucine, Isoleucine, phenylalnine, arginine and trrytophan and contains high level of iron, calcium and phosphorus (Dada et al. 1999). The galaction present in its abdominal gland serves as a medicinal substance of high immunological value, which cures tuberculosis, ulcer, asthma and circulatory disorders. Okonkwo et al. (2000) also pointed out that snail meat is useful in the treatment of some human diseases like anaemia, hypertension, and asthma e.t.c. while its shell can be used in the production of buttons, rings and other jewelry. It s unequivocally clear that the importance of improving snail production cannot be overemphasized. According to Olumo (1995), 14

15 protein function mainly in tissue growth, carbohydrate (in Nitrogen-free extract) provides the necessary energy for metabolic activities while calcium functions in shell growth (Akinmusi 1988). Stievenart (1992), Omole et al. (2000) and Ejidike (2001) pointed out the need to use complete balanced food in snail production. However, this study is to determine the different kinds of food and also the foraging behavior or feeding habit of Archachatina marginata. 1.1 JUSTIFICATION OF STUDY Most of the developing countries of the World, especially in Nigeria is currently been plagued with the alarming drop in per capital income and food production. Thus, the food deficient situation is indeed more serious with protein when compared with the availability of calories. According to Ademolu et al. (2004), the alarming increase in population implies that more people require the supply of protein in their diet because of its important role in human well being which includes growth, maintenance of hormonal and enzymatic activities and improvement of the defense mechanism of the body. Hence, Imevbore and 15

16 Ademosun (1988) assessed t he nutritive value of snail meat and discovered that it has a protein content of 88.37%. However, one of the major problem facing farmers in rearing snail is the non-availability of food that will meet the nutritive requirement of snails at cheaper cost. Hence, to solve this problem, there is a need to investigate the food and feeding habit of snails in order to provide their nutritive requirement at a cheaper cost and also enhance their growth performance using Archachatina marginata. 1.2 AIM AND OBJECTIVES OF STUDY Aim: To investigate the food and feeding habit of the giant land snail Archachatina marginata Swianson. Objectives of study are to: 1. Identify the food spectrum in growing snails. 2. Determine their feeding habits. 3. Determine the quantition of food intake. 16

17 1.3 SCOPE OF STUDY This study was restricted to the study on the food and feeding habit in giant land snail Archachatina marginata Swianson under labouratory condition. 1.4 LITERATURE REVIEW HISTORIC BACKGROUND In archaeological excavations, roasted snail shell has been found which indicates that snails have been eaten since prehistoric time (Rebecca et al., 2004). The act of farming snail was presumed to have started about 50 B.C. when snails were raised in small fattening units called cochlear garden. Snails belong to the kingdom animalia and phylum mollusca, which is the second largest invertebrate. They are characterized by the possession of shell. They may also be aquatic or terrestrial. Snails (especially the African giant land snail Archachtina marginata which is mostly found in Nigeria) are classified as mini-livestock (Ebenso, 2006) that serves as important source of animal protein in the diet if both urban and rural households in many parts of Nigeria (Adinya, 2010; Agbogidi 2011; Nwandu, 1999). It is one of the biggest sized specie of 17

18 snails and it lays large sized eggs which range from 5-15 eggs per clutch. Snails meat is nutritiously high up to 60% protein on dry matter basis, rich in essential amino acid and also high in iron to about 45-50mg/kg (Imevbore, 1990; Stievenart, 1992; Ebenebe,2000) SCIENTIFIC CLASSIFICATION OF Archachatina marginata Kingdom: Animalia Phylum: Mollusca Class: Gastropoda Super family: Achatinoidea Family: Achatinidae Genus: Archachatina Species: Archachatina marginata Subspecies: Archachatina marginata marginata Archachatina marginata ovum Archachatina marginata suturalis 18

19 Archachatina marginata egregia Archachatina marginata eduardi Archachatina marginata candefacta Archachatina marginata gravillei Archachatina marginata icterica Archachatina marginata common name is the giant West African snail or the banana rasps snail, is specie of air-breathing tropical land snail, a terrestrial pulmonate gastropod mollusk with the family Achatinidae DESCRIPTION OF Archachatina marginata Archachatina marginata is separated from Achatina species by its large, bulbous protoconch, as compared to the narrow, pointed spire of those species. The shell of the can grow up to 21 centimeters in height and 13 centimeters in diameter. The shell when magnified has the appearance of a woven texture (U.S. Department of Agric; 2015). Moreover, it is distinguished from related Archachatina species by two principal character; its subsutural, usually strongly marked engraved line separated from the suture by a narrow depressed area covered with irregular, low vertical 19

20 folds, the suture itself being straight or very slightly wavy, not crenulated. The engraved line starts on the fourth or fifth whorl and it s often deep and prominent, particularly on the body whorl; the second feature is a peculiar micro-sculpture of the body-whorl only visible to the proper magnification. It consists of numerous extremely fine, close-set or criss-cross lines, making the surface of the periostracum look as if it had been pressed with a very finely woven cloth. The embryonic whorls, when well preserved are densely covered with regular spiral and vertical rows of minute granulations, which become coarser on the first post-embryonic whorls (Bequaert; 2001). GEOGRAPHIC DISTRIBUTION OF A. MARGINATA The species occur in western African: Cameroun through Democratic Republic of the Congo and can be found in the Carribean, in Martinique (U.S. D.O.A.; 2015). It is still unknown how the specie reached Martinique but it is possible they are intentionally introduced as pets or by workers returning from West Africa (Robinson et. al.; 2015). Hence, the natural spread of this species is very slow; however, unintentional spread by individuals for foods and as folk medicine is very common (Science Daily; 2009). This specie has not yet become established in the United States, but 20

21 it is considered to represent a potentially threat as a pest and invasive species which could negatively affect agriculture, natural ecosystem or commerce. Therefore it has been suggested that this species be given top national quarantine significance in the United States (Cowie et. al.; 2009) MATING AND EGG LAYING Snails are hermaphrodites; they have both male and female reproductive organs but must mate with another snail of the same species before they lay eggs. Some snails may act as males one season and as females the next season (Rebecca and Sheldon, 2004). Other snails have been identified to play both roles at once and fertilize each other simultaneously. Mating is preceded with a courtship that involves the suitor piercing the body of the other individual with a simulating dart. This can sometimes be seen as a white splinter sticking out of the skin. Giant snails begin breeding when about a year old and mating occurs in the late spring or early summer after several hours of courtship. Second mating sometimes occurs in the summer. The biggest ecotype of snail species should be used for breeding. They should not have broken or perforated shell and should be healthy snails. Amusan and Omidiji (1998) observed 21

22 that fullness of flesh within the shell is an indication of good health and that healthy snails cannot withdraw its body far into the shell when irritated but the starved or those not in good condition withdraws its body far into the shell. In tropical climates, mating may occur several times a year. After mating, the snail can store sperm received for up to a year but it usually lays eggs within few weeks. Snails are sometimes interested in mating with another snail of the same species that originated from considerable distance away (Rebecca and Sheldon, 2004). Achatina achatina can lay between eggs per clutch. The eggs are elliptical and measure about 5mm long. They are usually laid in round-shaped holes dug 2-5cm deep in the soil but are occasionally laid on the soil surface. The incubating soil is also needed to be kept moist but not wet, maintaining a temperature of degree centigrade and relative humidity of above 80% (Amusan and Omidiji, 1998). If the eggs are exposed to heat, it will dry and harden and therefore will not hatch. They usually hatch days after laying. One to three days are required to complete hatching of each egg clutch and the size of the hatching depends on the size of the egg (Stievenart, 1996). Ejidike et al (2002), observed that hatchability is affected by dry soil 22

23 which adversely affect incubated snail eggs, thereby reducing hatchability of the eggs. Young hatchlings are normally kept in small baskets with tiny holes to avoid escape until they grow into bigger sizes GROWTH OF SNAILS In a snail population, some snails grow faster than the others under the same conditions. Some will take longer time to mature. The long maturity period has been suggested to help the species survive harsh weather condition. Several factors can greatly influence the growth of snails; they include, population density, stress such as noise, light, vibration, unsanitary conditions, irregular feedings, being untouched etc, feed, temperature, moisture and the breeding technology used. Adeparusi (2001) reported a reduction in growth rate of Archachatina marginata during the adverse condition of harmattan. They obviously went into aestivation with storage of water and a covering of epiphragm to prevent such external influence. He reported that a broken epiphragm was rapidly rebuilt in 2-3 days, while it takes two weeks for a broken epiphragm to disintegrate. 23

24 However, calcium helps in the growth of snails, thus, Amubode and Ogogo (1995) used 70% bone meal and 30% oyster shell in diets for Archachatina marginata and it increased their growth rate. Rebecca and Sheldon (2004) reported that snails may eat paint or attack walls of buildings and even eat dirt while seeking calcium. Hence, the size of the shell of a new born snail depends on the egg size since the shell develops from the egg s surface membrane. As the snail grows, the shell adds and eventually it will develop a flare or reinforcing lip at its opening. This shows that the snail is now mature and there will be no further growth. African land snails cal live for 5-6 years although, just a few manage to live up to 15 years before they die (Akinomide; 1997) FOOD AND FEEDING PATTERN OF SNAILS African giant land snails are considered as omnivorous animal based on their feeding habit. They are known to feed on decaying materials such as dead plants and animal carcasses; thus; they are termed as good endconverters. They also feed on their own wastes (coprophgia) and eat up their dead or weak mates under certain conditions (cannibalism). Some of the plant material which they feed on include; tubers: such as carrots, cocoyam, yam and sweet potatoes; fruit such as avocado pear, guava, oil 24

25 palm, ripe pawpaw, ripe plantain, pineapple, orange, mango and bread fruit. Other materials include; plant leaves such as pawpaw, sweet potato, and cocoyam, fluted pumpkin and household wastes: yam peel, cassava, bread, remnant foods without table salt, rotten plantain. Amusan and Omidiji (1998) pointed out that snails when fed with waterleaf lose weight, become inactive with higher incidence of cannibalism and death. However, the growth obtained through feeding young Archachatina marginata on plant materials supplemented with compounded feed was significantly better than that obtained through feeding it with only plant food materials (Ejidike et al., 2002). The growth of snails like other animals differs with respect to what they are fed. There is also a strong and positive relationship between nutrient content of the feed and the growth of snails (Okonkwo et al., 2000). Adu et al. (2002) pointed out the need for research studies on the use of compounded ration for snails in order to solve the problem of scarcity of fruits, tuber and leaves during the dry season. The provision of adequate feed (Okonkwo et al., 2000), supplementary vitamins, calcium, minerals and water capable of thwarting the aestivation cycle and thereby enhancing greater productivity besides preventing drug wastage and bacteria growth over time. Amusan and 25

26 Omidiji (1998), pointed out the need to avoid salt in snail feed since it possibly coagulates the slimy salivary systems and deadens the foot or flesh of the snail resulting to instant death. However, studies have shown that the snails will eat during the day but they prefer to eat at night. Hence, domesticated snails typically consume food that is high in protein and low in fats. Also, studies that were done to test food on the domesticated snails have shown that poultry droppings have been the most effective meal for both growth and weight gain (Ademolu et al, 2005) CLIMATIC CONDITIONS AND SOIL CHARACTERISTICS The countries in which Archachatina marginata is established have tropical climates with warm, mild year round temperatures and high humidity (Raut et. al, 2002). The species occurs in agricultural areas, coastal areas and wetlands, natural and planted forests, riparian zones, scrublands and urban areas (Raut et. al, 2002). These snails thrive in forest edge, modified forest and plantation habitat (Raut et. al, 2002). Rebecca and Sheldon (2004) reported that a mild climate (59-75 o F) with high humidity (75%-95%) is best for snail farming, though most varieties can 26

27 stand a wider range of temperatures. Thus, humidity that is lower than required will disturb the production due to excessive evaporation from the body of the animal. Such a condition can lead to the emergence of illness and can cause death. They pointed out that the optimal temperature is 70 o F for many varieties. When the temperature falls below 45 o F, snails hibernate. Under 54 o F, the snails are inactive and under 50 o F, all growth stops. When the temperature raises much above 80oF or conditions become too dry, snails aestivate. Wind increases moisture in snails, hence, to prevent snails from drying, snaileries should be situated in sites which are protected from wind since it affects the humidity and temperature of the environment. Also, wind can be held by planting big trees around the farm. Trees, apart from reducing wind, can also provide shade and increase the humidity. Snails also need damp, not wet environments, although, snails need moisture, wet or water logged, soil must be drained to make it suitable for them. Snails breathe air and may therefore be drowned in overly wet surroundings. Rebecca and Sheldon (2004) reported that snails need soil in which to lay eggs. Dry soil is not suitable for the preparation of a nest nor is soil that is too heavy. In clay soil that becomes hard, reproduction may 27

28 decrease because the snails are unable to bury their eggs and the hatchlings have difficulty emerging from the nest. Hatchability of eggs also depends on soil temperature, soil humidity and soil composition. Soil consisting of 20% to 40% organic material is good (Rebecca and Sheldon, 2004). Ejidike (2002) reported that snail soil tolerance differs and that while some species prefer acid soil of low ph of about 4.5, most of them prefer slight alkaline soil with a ph range of Snailery soil is considered a good breeding site for most infectious microorganisms and pest of land snails. Snailery soil is advised to be heat treated either wet or dry. Sterilization is necessary to destroy soil ants and their eggs because of the devastating nature of the ants on snails. Akinomide (1997), advised that the use of disinfectants or other chemicals is better avoided to prevent toxicity of drug accumulation within their body since they are in frequent contact with the soil and often taking in soil particles. He further emphasized that periodic heat treatment of the soil should be carried out twice a year or when some ants or pest are sited therein. 28

29 1.4.9 PREDATORS, PARASITES AND DISEASES: A snail farmer must be aware of predators, parasites and diseases of snail in order to reduce mortality to the barest minimum. The predators of snail include the field mice, rats, frogs and toads, domesticated birds such as ducks and turkeys, lizards and snakes, beetles, millipedes and centipedes. The frogs have been observed to take only the young snails while the reptiles eat both the eggs and the snails. Using cover nets over the pens can prevent bird predation. Other predators can be kept out of the pen by building fences between 15 and 30 cm high and digging well into the ground around the pens. Left over feed must always be removed regularly from pens since some predators like rat and field mice are attracted by the uneaten feed. A fly, Alluaudihella flavicarous has been identified as the major parasite on snails. This fly belongs to the same family as the housefly and the adult resembles the adult housefly. The fly lays eggs in the snail s shell or on the snail. The eggs hatch in about 1 week and the small, cream-colored worms start feeding on or in the body tissue. They feed until the body is reduced to a putrefying mass, and then pupate within the shell. After a 10- day incubation period, the adults emerge. Snails can best be protected against these flies by covering the pens with nylon mesh. Ectoparasitie 29

30 mites are also found on the snails in hutch boxes. These appear to be secondary parasites usually occurring on inactive snails. Obi et al (2001) identified several entero-pathogenic bacteria and fungi among African giant land snails around Ibadan metropolis. Akinomide (1997) also reported that bacteria, particularly entero-bacteria may be transmitted to people who handle or eat snails. In Italy today wild snails are no longer considered as food source as stringent health regulation for consumption of food are now in place (Sonya, 2003). This is necessary to protect the consumer against collected snails that may have ingested toxic plants or potentially harmful chemicals. Two major diseases have been identified to attack snails. The first disease is a bacterial diseases caused by pseudomonas. This leads to intestinal infections, which may spread rapidly amongst dense populations of snails. The second disease is caused by fusarium, which parasitizes the eggs of snails. The affected eggs turn reddish brown and development stops. This disease is referred to as rosy egg disease. Basic hygiene is known to prevent the spread of diseases. Pens should be cleaned out regularly to remove excreta and uneaten feed, as well as any other decaying matter that may serve as substrate for pathogenic organism. The soil in the hutch boxes should also be sterilized. Akinomide (1997) 30

31 suggested that newly purchased snails should be given an alum, lime or lemon solution bath before finally bringing them in since the astringent property of the solution reduces the level of snail ecto-parasites and keeps them clean ECONOMIC IMPORTANCE OF A. MARGINATA Snails feed on a large variety of plants, mainly fruits. Plants included in the snail s diet are bananas, lettuce, peanuts and peas, some of which are important crops in certain economies. The giant West African land snail Archachatina marginata is one of the worst invasive species in the world and it s extremely devastating to any species that it affects. However, the more prevalent problem with the spread of the snail as invasive species is that it is often a carrier of the disease rat lungworm. Within humans this causes the disease Eosinophilic meningoencephalitis, which is what makes the snails spread to North America problematic. If the snail continues to spread, it could potentially be a problem to the health of people all throughout North America from Cuba to the United States (Vazquez, 2015). Archachatina marginata can live up to 10 years and attain sexual maturity at 9-10 months under laboratory conditions. In addition to being 31

32 agricultural pest, they act as the reservoir host of rat lung parasite which causes Eosinophilic meningoencephalitis in humans and are seen as a threat to public health because of this (White-Mclean, 2011). 32

33 CHAPTER TWO MATERIALS AND METHOD 2.1 LOCATION OF STUDY: The experiment was conducted at Imo state University, Owerri Nigeria. Owerri, lies within longitude E and latitude 5 o N. The climate of the study area is typically tropical with relative humidity ranging from 75% to 90% and mean temperature of C. The rainy season is between April to October and dry season between November to March. 2.2 FOOD AND THEIR SOURCES: Fruits and vegetables were the test food used for the experiment. All the foods were gotten from the garden. 2.3 EXPERIMENTAL ANIMALS AND THEIR SOURCES African giant land snails (Archachatina marginata marginata) were used in the experiment. The snails were purchased from Eke-ukwu market in Owerri. Thus, fifteen snails were used for the study. The snails were divided into three Groups according to their weight as seen in the table below (with each Group having five snails). 33

34 Table 1: The experimental snails in relation to their body weight; Sizes of Snail 1(g) Snail 2 Snail 3 Snail 4 Snail 5 Mean snails (g) (g) (g) (g) weight (g) Small Medium Large Vivaria: The snails were housed in baskets measuring 30cm in length and 13cm in width. The basket was properly perforated for easy movement of air, in and out of the basket. The basket was also filled to 5cm depth with loamy soil exposed to sunlight to get rid of harmful soil microorganism. The soil was moistened regularly to keep favourable humidity for the snail. Feeding and Watering: Food and water were given to the snails ad libitum. The food was moistened before supply to allow for easy ingestion and to prevent respiratory difficulty that can be caused by dusty feed. Sanitation: Fresh food that was free from mould was given to the snails every day. Leftover food was removed from the feeding trough. Clean water was also supplied to them. The plastic trays used for food and water 34

35 supply were cleaned and washed each day before placing food or water. Their faeces were scooped out of the basket to prevent microbial infestation. 2.4 EXPERIMENTAL METHOD: Two methods were used in carrying out the experiment; they include: quantitative and observational method. Quantitative method: In this method, the snails were weighed before they were placed in their Vivaria according to their weight. Their feeding responses were also determined by measuring their feed intake using the formulae: Feed intake = Quantity of food given Left over Observational method: in this method, the pattern of feeding was observed i.e; observing whether they are nocturnal or diurnal feeders and also their mode of feeding on the foods. 35

36 CHAPTER THREE RESULTS 3.1 FOOD SPECTRUM: Table 2 shows the different variety of fruits and vegetables that were found to be edible by Archachatina marginata in this study. Table 2: Experimental fruits with their scientific name FRUITS COMMON NAME SCIENTIFIC NAME Orange Sweet orange Citrus sinensis Pear Avacado pear Persea americana Banana Banana Musa acuminate Apple Apple Malus pumila Tomatoes Tomato Solanum lycopersicum Watermelon Water melon Citrullus lanatus Palm fruit African palm Elaeis guineensis Pawpaw Pawpaw Asimina triloba (Carica papaya) Grape African grape Vitis vinifera Cucumber Cucumber Cucumis sativus 36

37 Table 3: Experimental vegetables with their scientific name VEGETABLES COMMON NAME SCIENTIFIC NAME Pawpaw Pawpaw Asimina triloba (Carica papaya) Cabbage Cabbage Brassica oleracea Pumpkin Fluted pumpkin Telfairia occidentalis Cocoyam Cocoyam Xanthosoma spp. & Colocasia spp. Water leave Water leave Talinum fruticosum Cassava Cassava Manihot esculenta Palm African palm Elaeis guineensis Pepper Pepper Capcicum annuum Uziza Uziza Piper guineese This result on the food spectrum is comparable to that of the result obtained by Omole (2003) who stated that Archachatina marginata have voracious appetite which is the ability to eat large varieties of food (mostly plant materials). 37

38 3.2 PREFERENCE: Archachatina marginata showed a significant level of difference in the amount of the different fruits and local leaves fed to them which revealed their preference for certain foods as shown in Tables 4 and 5. Table 4: Food items in the descending order of preference (fruits) Fruit items Scientific name Preference in descending order Pawpaw Asimina triloba (Carica papaya) 1 st Cucumber Cucumis sativu 2 nd Banana Musa acuminate 3 rd Water melon Citrullus lanatus 4 th Orange Citrus sinensis 5 th Pear Persea Americana 6 th Tomatoes Solanum lycopersicum 7 th Apple Malus pumila 8 th Palm Elaesis guineensis 9 th Grape Vitis vinifera 10 th 1 st =highest; 10 th = lowest 38

39 Table 5: Food items in the descending order of preference (Vegetables) Vegetables Scientific name Preference in descending order Pawpaw Asimina triloba (Carica papaya) Cabbage Brassica oleracea 2 nd Cassava Manihot esculenta 3 rd Water leave Talinum fruticosum 4 th Cocoyam Xanthosoma spp. 5 th Pumpkin Telfaria occidentalis 6 th Mango Mangifera indica 7 th Uziza Piper guineese 9 th Pepper Capicum annuum 10 th 1 st = highest; 10 th = lowest 1 st From the table above, the result shows that Archachatina marginata prefer pawpaw fruit and leave to other fruits and local leaves. Also, they avoided the pepper and Piper guineese (Uziza) leave fed to them, thus complying favourably with the observation made by Olaniya (2004) who stated that A. marginata tend to avoid plants that have pepper-like taste. Also, in the case of African grape fruit and Colocasia spp. of cocoyam leave, they avoided them when the fruit and leave were presented. 39

40 3.3 FOOD INTAKES AS A PROPORTION OF BODY WEIGHT Table 6: Food intake (FRUITS) as a proportion of body weight Fruits Scientific Sizes of Food Mean Food name snails intake weight intake/body (g) of weight (%) snail(g) Pawpaw Asimina Small triloba(carica Medium papaya) Large Cucumber Cucumis Small sativu Medium Large Banana Musa Small acuminate Medium Large Water Citrillus Small melon lanatus Medium Large Orange Citrus Small sinensis Medium Large Pear Persea Small americana Medium

41 Large Tomatoes Solanum Small lycopersicum Medium Large Apple Malus pumila Small Medium Large Palm Elaeis Small guineensis Medium Large Grape Vitis vinifera Small Medium Large

42 Table 7: Food intake (VEGETABLES) as a proportion of body weight Vegetables Scientific Size of Food Weight Food name snails intake of snail intake/body (g) (g) weight (%) Pawpaw Asimina Small leaves triloba(carica Medium papaya) Large Cabbage Brassica Small oleracea Medium Large Cassava Manihot Small leaves esculenta Medium Large Water Talinum Small leaves fruticosum Medium Large Cocoyam leaves Xanthosoma spp. Small Medium Large Pumpkin Telfaria occidentalis Small Medium Large Mango Mangifera Small

43 leaves indica Medium Large Uziza leaves Piper guineese Small medium Large Pepper leaves Capsicum annum Small Medium Large Cocoyam leaves Colocasia spp. Small Medium Large From the result (table 6&7) above, Archachatina marginata did not feed according to their sizes because smaller snails which are in Group 1 having the mean weight of 43g fed mostly than other Groups which are larger in size. 43

44 CHAPTER FOUR DISCUSSION AND CONCLUSION 4.1 DISCUSSION The observation made on the food and feeding habit of Archachatina marginata from this study supports the observation made by Omole (2003) who stated that Archachatina marginata have voracious appetite based on the different varieties of fruits and leaves they fed on. However, previous studies have also shown that Archachatina marginata can also feed on grain wastes, flowers, and carcasses like dead birds, ants and termite (Akintomode, 2004; Adeyeye, 2001). Thus, in support of the observation made by Olaniya (2004), based on the food spectrum, Archachatina marginata usually prefer fresh juicy succulent leaves and fruits to dry ones (Table 4&5). Olaniya further observed that snails may avoid hairy plants that produce offensive and harmful chemicals and also plants that have pepper-like taste. Hence, this observation made by Olaniya is in compliance with the one made in this study because the snails tend to avoid the Uziza leave and the pepper leaves which were given to them instead; they dig holes into the soil which shows that Archachatina 44

45 marginata consumes soil, a phenomenon which has been previously reported by Richardson, 1975 and Williamson, However, Williamson (1976) suggested that soil may act as a digestive aid and is possibly important for nutrient acquisition. Other persons who also observed soil consumption in their studies on snails such as Elmslie (1998), Fretter (1962) and Speiser (1991) suggested that snails may extract humic acids, calcium or digesting soil organisms from soil particles respectively. Although based on these different suggestions, it appears that the role of soil in the nutrition of snails is not fully understood but from this study it seems that soil might have a nutritive role in snail which is in compliance with the suggestion made by the above persons. Furthermore in this study, the giant land snail Archachatina marginata preferred fruits to leave which is in relation to the research made by Ejidike (2001) who stated that younger snails appear to prefer leaves to fruits while older and larger snails would go for fruits when offered a choice between leaves and fruits. Based on the feeding habit and mode of feeding; the results of this study that the Archachatina marginata emerged to feed mostly at night and early hours of the morning between the hours of 10.00pm and 1.00am; also 4.00 am and 7.00am respectively. Thus, this observation 45

46 agrees with the findings of Amusan and Omidiji (1998). Hence, with this observation, Archachatina marginata are not just nocturnal feeders but they feed well when the humidity is appropriate for them which means that the time of feeding depends on the relative humidity of their surroundings; this observation supports the findings of Akinnusi (2002). Furthermore, during feeding, the snails scrape their food rather than chew it like humans. Hence, a flexible structure called the radula in the snail s mouth is lined with neatly organized rows and columns of tiny tooth-like projection. Thus, the snails move their radula over the food and scrape off bit of it and swallow. The sound of the snail s radula scrapping was also observed. However, the snail teeth are tiny and delicate and not as strong as other livestock teeth hence snails prefer succulent feeds to others as observed by Omole (1998). This preference can be observed in the feed intake (table 4&5) which indicated that ripe pawpaw fruits and leaves were preferable to snails. Also snails are very sensitive through the help of their tentacles; they can detect fruits and leaves that are toxic and harmful to them. In addition, the snails did not feed according to their sizes because in relating the sizes of the snails with their food intake according to this study, the smaller snails weighing 43g fed mostly than other Groups. Zero 46

47 mortality was recorded in this study which indicates the safety inclusion of cassava leaf; thus, the result supports the fact that Archachatina marginata are hardy and well adapted to the environment as observed by Oluokun (2005). 4.2 CONCLUSION AND RECOMMENDATION Archachatina marginata from this study showed that it has a wide range of food spectrum and also have the ability to distinguish between edible and harmful foods by exploring the food fed to them through their tentacles. Thus, they showed preference to both pawpaw fruits and its leaves and also fed mostly at night and the early hours of the morning when the humidity is high and favourable for them which means that if appropriate environment is provided for them they can also feed during the day. Therefore, I recommend those farmers, students and other personnel who are into snail farming should ensure that they feed their snails with food that are edible to them especially since they have a wider range of food spectrum and should also ensure that they feed them with pawpaw fruits and leaves and mostly succulent fruits and vegetables. Moreover, 47

48 they should also make sure that an appropriate environment with relative humidity ranging from 75%-90% is provided for them in order to increase the rate of snail production which will eventually lead to a high intake of protein among people in Nigeria when the snails are consumed. 48

49 REFERENCES Ademolu, K.O, Idowu, A.B, Mafiana, C.F, and Osinowo, O.A (2004), Performance, proximate and mineral analyses of African giant land snail (Achachatina marginata) fed different nitrogen sources. African Journal of Biotechnology Vol. 3 (8) pp , August, Adeperusi E.O. (2001) Seasonal Effects On The Growth Of Archachatina Marginata. Proc. Of 26th Annul. Conf. Of NSAP. Vol 26, 2001, Pp Adesope, O. M, (2000). Attitudes of household in A Niger Delta zone towards snail meat consumption. In: Ukachukwu S.N et al, (eds) Animal Production in the New Millennium: Challenges and options. Zaria: NSAP Secretariat. Adeyeye, E.I., (1996). Waste Yield, Proximate And Mineral Composition Of Three Different Types Of Land Snail Found In Nigeria. Int. J. Food Sci. And Nutr., 47: Adinya, I. B. (2006). Snail Production. Extension Bulletin Guide, 1(1), 1-3. Adinya, I. B. and Ibekwe, H. A. (2010). Allocative efficiency constraints in snail (Archachatinamarginata) production by small scale snail farmers in Cross River State, Nigeria. Journal of Agriculture and Environment for International Development, 104 (3-4),

50 Adu O.A, A.O. Ojurongbe and A.J Omole (2002) Performance and Carcas Analysis of Giant land Snails (Archachatina marginata) fed supplementary diets. Proc. 27th Ann. Conf. Nig. Soc. For Anin. Product (ASAP), March Fed Univer. of Tech. Akuref Nigeria. Agbagha, F. M., Ezema F.U. And Omeke, B.C.O. (2000) Studies Of Mangaement Effects On Fertility Of Purbred And Crossbred Exotic Gilts In Two Breeding Farms At Nsukka. Nigeria Journal Of Animal Production. 28(1)Pg 20. Agbogidi, O. M. and Okont, B. C., (2011). Reducing poverty through snail farming in Nigeria. Agriculture and Biology Journal of North America, 2(1), Akinnusi,O.(1998). Live history of Archachatinamarginata (Calachatinaswainson). A paper Presented at Silver Anniversary of Animal Conference and Inaugural Conference and Inaugural Akinnusi O. (1998) Introduction To Snail Farming. Omega Science Publisher, Tinuoso House, Lagos, Nigeria. Akinnusi O.(2002); Introduction To Snails And Snail Farming, Triolas Publishing Company, Abeokuta, Pp

51 Akinnusi, O. (2000). Snail Rearing Case Study Of Abeokuta, Ogun State, Nigeria. Proceeding Of 5th Annual Conference Of Animal Science Association Of Nigeria, Port Harcourt Nigeria. Sept Pp Akinnusi. O. (1998): Life History Studies Of Archachatina Marginata (Swainson). Proceedings: Silver Anniversary Conference Of NSAP/WASAP Inaugural Conference Held In Abeokuta Ogun Sate. Nigeria 21 Oct-26th March 1998: Akinomide, T.O (1997).The African Giant Land Snail. Alamsek Press Limited Ijebu Ode,Nigeria PP Akintomida TO (2004). Tropical Snail Farming. 1st Ed. Oak Ventures Abeokuta, Nigeria. Amubode F.O And Ogogo A.U. (1995). Performance Of Snails (Archachatina Marginata) Fed Varying Levels Of Calorie-Protein Supplementary Diets. Nigerian Journal Of Forestry 24 (1 And 2): Amusan J.A And Omidiji M.O (1998), Edible Land Snails. A Technical Guide To Snail Forming In The Tropic. Verify Printers Ibadan AOAC (1990). Association Of Official Analytical Chemist, Official Methods, 13th Edition, Washington DC. 51

52 Awesu, M. O. (1980). The biology and management of the African Giant Land Snail (Archachatinamarginata). M. Phil Thesis, University of Ibadan. Ayodele I.A., Asimalowo A.A. (1999); Essentials Of Snail Farming. Agape Prints, U.I. Ibadan, Pp. 51 Bailey, SER (1989). Foraging Behaviour Of Terrestrial Gastropods: Integrating Field And Laboratory Studies. Journal Of Molluscan Studies 55: Breinholt,K.A, Gowen,F.A And Nwosu C.C (1981).Influence Of Environmental And Animal Factors On Day And Night Grazing Activity Of Imported Holstein Freisian Cows In The Humid Lowland Tropics Of Nigeria. Trop. Animal Produc.6:4. Cowie R.H., Dillon R.T., Robinson D.G., Smith J.W. (2009). Alien Non-Marine Snails And Slugs Of Priority Quarantine Importance In The United States: A Preliminary Risk Assessment American Malacological Bullentin 27: Dada, S.A.O, ABU, A.O Okeowo, T.A Badmus, O.R (1999). A.J. Biomed. Resi 2: 2 ( ). Daouda A.I.H.H (1993), The Calcium In The Nutrition Of Giant African Snail Achatina Achatina.B.E.D.M 1 (2):

53 Duncan D.B (1955). New Multiple Range and Multiple F-tests. Biometrics. 11: Ebenebe, C.I, (2000) Mini Livestock Production in Nigeria. The present and future Proceedings of 5th Annual Conference Ebenso, I. E. and Okafor, N. M. (2002). Alternative diet for growing Archachatina marginata snails in south-eastern Nigeria. Tropical Science 42 (3) Ebenso, I. E., Chukwu, S., Udo, S., Ukpai, C. U., Udo, M. T., Umanah, U., Isang, A. and Akam, A. (2004). Some behavioural responses of Limicolaria aurora exposed to gramoxone. Nigerian Journal of Physiological Sciences 19 (1-2) Ebenso, I. E., Isaac, L. J. and Obasi, O. L. (2002). Mating behaviour of African giant land snail Archachtina marginata. Nigerian Journal of Forestry 32 (1) Ejidike B.N (2002). Snail Rearing Practices in Southern Nigeria. Proceeding of 27Th Annual Confe. Of NSAP.PP

54 Ejidike B.N (2004). Growth Performance And Nutrient Utilization Of African Giant Land Snail (Archachatina Marginata) Hatchlings Fed Different Protein Diets. Food,Agriculture And Environment Vol. 2(1) Ejidike B.N, T.A Afolayan And J.A. Alokan, (2002) Influence Of Food And Season On Egg Production Of African Giant Land Snail (Archachatina Marginata). Proc. 27th Ann. Conf. Nig. Soc. For Anim. Prod. (NSAP), March 17-21, Fed Univ. Of Tech. Akure., Nigeria. Pg Ejidike B.N. (2001), Comparative effect of supplemental and complete diets on the performance of African giant land snail (Archachatina Maginata). Proceedings of the Nigeria Society for Animal Production, volume 26, 151, Ejidike BN, Afolayan TA And Agbelisi EA (2000). Growth Response Of African Giant Land Snail (A. Marginata) On Supplementary Diet Of 25% Crude Protein Level. Proceedings Of The 25th Annual Conference Of Nigeria Society For Animal Production (NSAP), March Umudike, Nigeria, Pp Ejidike, B. N. and Omisade I. A. (2007): Evaluation of dry season rearing of African giant snail (Archachatina marginata) on different food type and apartments.journal of Fisheries and aquatic Sciences 2 (5):