ABSTRACT
The research work assessed the effects of parent body weight on egg size and egg number of African Land Snail (Archachatinamarginata).
60 snails were reared. All the snails were exposed to the same diet and experimental procedure and their weight was taken on a weekly basis.
The experiment was carried out for 12 weeks using three wooden cages.
The number of egg laid in each cage per week was recorded and the sizes were also recorded
The result shows that parent snail with moderate weight thrived better in terms of food consumption and egg laying with size.
It is thereby recommended that the parent snail should not be too old nor too small in order for them to be active in terms of reproduction.
TABLE OF CONTENTS
CHAPTER ONE
INTRODUCTION
1.0 Background of the Study
1.1 Objectives of the Study
1.2 Specific Objectives of the Study
1.3 Statement of the Problem
1.4 Scope of the Study
1.5. Research Hypothesis
1.6 Delimination of the Study
1.7 Limitation of the Study
1.8 Definition of Terms
CHAPTER TWO
2.0 Literature Review
2.1 Description of Snails
2.2 Biology of Snails
2.3 The Shell
2.4 Locomotion
2.5 Housing of Snails
2.6 Archachatina Marginata
2.7 Temperature and Humidity
2.8 Soil Characteristics
2.9 Feeds and Feeding of Snail
2.10 Egg Laying
2.10.1 Nutritional Important of Snails
2.10.2 Economic Importance of Snail
2.10.3 Medical Importance of Snails
CHAPTER THREE
3.0 Materials and Methods
3.1 Experimental Site
3.2 Housing Unit
3.3 Research Method
3.4 Experimental Design
3.5 Routine Operation
3.6 Method of Data Collection
3.7 Preparation of Experiment Diet
3.8 Instrument for Data Analysis
CHAPTER FOUR
4.0 Data Analysis and Presentation of Result
CHAPTER FIVE
5.0 Summary, Conclusion and Recommendation
5.1 Summary
5.2 Conclusion
5.3 Recommendation
References
CHAPTER ONE
INTRODUCTION
1.0 BACKGROUND OF THE STUDY
Snails are invertebrates (without bone), shell bearing animals that are passive or inactive during the day but, very active in the night, at dusk or when it rains and usually find in a cool place. Snail is a terrestrial animal of approximately 100,000 species of molluscs, of the phylum Mollusca, or alternately, any of the twelve species of land pulmonate gastropods used as human flood. It is air-breathing, usually herbivorous, with a complex hermaphroditic reproductive system, through demanding cross fertilization. It usually hibernates, forming a membrane over the shell opening (Akinnusi, 2004). Land snails move by gliding along on their muscular foot, which is lubricated with mucus and covered with epithelial cilia. This motion is powered by succeeding waves of muscular contractions that move down the ventral of the foot. They produce mucus to aid in locomotion by reducing friction. Snails also have a mantle, a specialized layer of tissue which covers al of the internal organs as they are grouped together in the visceral mass. The mantle is attached to the shell and creates it by secretion. Land nails need a good supply of calcium in the diet and environment to produce a strong shell. Snail can repair damage to its shell overtime of its living conditions improve, but sever damage can be fatal. Most land snails bear one or two pairs of tentacles on their head. In most land snails the eyes are carried on the first (upper) set of tentacles called ommatophores which are usually roughly 75% of the width f the eyes. The second (lower) set of tentacles acts as olfactory organs. Both set of tentacles are retractable in land snails.
Snail meat has been consumed by humans worldwide since prehistoric times. It is high in protein (12-16%) iron (45-60mg/kg), low in fat, and contains almost all the amino acids needed by human. A recent study has also shown that the glandular substances in edible snail meat causes aggulutination of certain bacteria, which could be of value in fighting a variety of ailments, including whooping cough. In west Africa, snail meat has traditionally been a major ingredient in the diet of people living in the high forest belt (The forested area other than savannah forest). International trade in snails is flourishing in Europe and North America. However, in spite of the considerable foreign and local demand, commercial snail farms such as those in Europe, South East Asia and the Americas hardly exist in Africa. In Ghana, Nigeria and Cote d’Ivoire where snail meat is particularly popular, snails are gathered from the forest during the wet season. In recent years, however, wild snail populations have declined considerably, primarily because of the impact of such human activities as deforestation, pesticide use, slash and burn agriculture, spontaneous bush fires and the collection of immature snails. It is therefore important to encourage snail farming (heliculture) in order to conserve this important resources.
Edible snails species of African Origin
Achatina achatina- giant snail, tiger snail (Ghana)
Achatina fulica
Archachatina marginata
ACHATINA ACHATINA
Common name: giant snails, tiger snails (Ghana)
Local name: (Corresponding language within parenthesis)
Gambia: honuldu
Sierra Leone : Konk
Liberia : dain, (Nano), drain (Gio)
Ghana: abobo (Ewe) elonkoe (Nzima), Krekete (Hausa)
Nwapa (Akan), Wa (Ga), Ilako, Isan (Yoruba)
Nigeria: Katantawa (Hausa), Ilako, Isan (Yoruba)
East Africa: Kanokano (Swahili)
Achatina fulica
Common name: garden snail, foolish snail
Ghana: awa (akan)_
Nigeria: eesan or ipere (Yoruba)
Kenya: ekhumuniu (Luhyal, kamniyo (Luo)
East Africa: Kano Kano (Swahili)
Archachatina marginata
Common name: big black snail, giant African land snail
Liberia: proli (Kepelle)
Ghana: Pobere (Akan)
Nigeria: Igbun (Yoruba), Ejuna (Ibo)
Archachatina Marginata is a large snail generally growing to about 20cm and a live weight of 500g. the shell is much less pointed than the achatina species striation on the shell may give the appearance of a woven texture. The head of the snails is dark- grey, its foot is a lighter shade.
Achatina fulica is a large snail reaching 20cm and a maximum diameter of 12 cm. the conical, spiraled is predominantly brown with weak, darker bounded markings across the spiral. Coloration is highly variable, depending on diet. A mature shell average 250g in weight.
Achatina achatina snails are reputedly the largest land snails in the world. They can grow up to 30cm in body length and 25cm in shell height.
Average adult shell length is 18cm with an average diameter of 9cm. the conically shaped, fairly pointed shell is brownish with a characteristics stripe pattern.
1.1 OBJECTIVES OF THE STUDY
The overall objectives of the study is to find out the effect of parent body weight on the egg size and egg number of giant African land snail. (Archachatina Marginata) on different sizes of parent snail.
1.2 SPECIFIC OBJECTIVES OF THE STUDY
- To determine the weight gain of the parent snail
- To determine the shell growth/gain of the different sizes of snail
- To determine the influence of weight of different sizes of snail on egg number and egg size.
- To determine the egg size of different sizes of parent snail
- To determine the egg number of different sizes of snail.
1.3 STATEMENT OF THE PROBLEM
This study is interested in finding solution to the following problems:
– To determine the parent body weight on Egg sizes and Egg number
– Adaptability to weather condition in the wooden cage
– Effect of feed on parent body weight of different sizes of snail.
1.4 SCOPE OF THE STUDY
This project work covers the parent body weight on the Egg size and Egg number of using three different sizes of giant African land snail. In this study, 60 snails were used and they were divided into three groups with three different sizes of giant African land snail for a period of twelve (12) weeks.
1.5 RESEARCH HYPOTHESIS
Whether the weight will have positive influence on egg size and egg number
= Whether the weight will have negative influence on egg size and egg number
= Whether the sizes of different parent snail will have positive or negative influence on egg size and egg number
1.6 DELIMINATION OF THE STUDY
This study is limited to the Agricultural Education Department of Federal College of Education Osiele, Abeokuta. The research was carried out in the animal unit of the college. It is therefore important that the environment in which the research work will be carried out is favorable and conducive.
1.7 LIMITATION OF THE STUDY
The rearing or keeping of snails in the world is generally confronted with myriad of problem (Orisawuyi Y.A. (1989) and this project on which the researcher is reporting is not an exception. The researcher faced financial constrains because it is almost virtually impossible to engage in any transaction without monetary involvement. The financial constrains therefore, constituted a limitation to this study most especially the cost of purchasing the snails and concentrate that is compounded feed given to them.
1.8 DEFINITION OF TERMS
AESTIVATOIN: The state of dormancy during the dry season (Warm Season)
AGGLUTINATION: The state of being clumped together, as if glued.
CLUTCH: Number of egg produced or incubated at the same time
COLDBLOODED: Having a body temperature that varied according to the external climate
ECTOPARASITE: A parasite that lives externally on its host.
FEEDINGSTIMULANT: A food component that induces feeding
HAEMOLYMPH: The snail’s body fluid
HELICULTURE: A system of raising snails in enclosure indoors and outdoors.
HUMIDITY: Clampness, particularly at the air
INCUBATIONPERIOD between the laying and hatching of eggs.
MOLLUSC: An invertebrate animal usually has a shell.
PREDATOR: an animal that preys on other animals
PUTREFY: Decay or decompose with a fetid (foul) smell
SNAILERY: Enclosure or pen in which animals are reared.
TENTACTLES: A retractable structure in animals, bearing sense receptors and used to obtain food.
VISCERA: The soft, internal organs of the body