African Snail Achatina Research Articles

EFFECT OF CLOVE OIL ON THE BIOCHEMICAL PROFILE OF OVOTESTIS AND HEPATOPANCREAS OF Achatina fulica

The giant African snail Achatina fulica is widespread across the subtropical and tropical countries and has picked up the global pest status. Its voracious feeding capacity and protandrous reproduction makes it almost invincible once established. Measures to combat its menace have for long focussed on chemical molluscicides. However the rising environmental sensitivity in the past few decades has attracted the use of natural compounds to target this pest. The current study was aimed to evaluate the impact of clove oil on the biochemical profile of its ovotestis and hepatopancreas. The snails were randomly divided into three groups i.e., control, vehicle treated group (1% Tween 80) and clove oil treated group. Snails in the clove oil treated group were subjected to subacute doses of clove oil (20% and 60% of LD50 value/24 hrs) by topical application. The activity levels of vital enzymes namely acetylcholinesterase, acid phosphatase, alkaline phosphatase, protease and lactic dehydrogenase were pertinently altered in the ovotestis and hepatopancreas of the clove oil treated snails as compared to the control. Contents of important biomolecules like DNA, RNA, protein, and phospholipids were reduced, the level of lipid peroxidation was significantly enhanced with a concomitant decrease in glutathione content in clove oil treated groups vis-a-vis control in both the tissues studied, highlighting the toxic effect of clove oil to the snail. Thus it is suggested that clove oil can be used in controlling the population of this harmful pest.

Physical and Morphological Properties of Snail (Achatina Fulica) Shells for Beneficiation into Biocomposite Materials

In this study, microhardness and flow strength (tensile) of a shell of an African Giant snail (Achatina Fulica) were studied as a function of indentation load. The influence of loading direction on the hardness of the nacreous and prismatic structure of the shell material was analyzed. The results revealed that microhardness measured on the shell was dependent on the load on the nacreous and prismatic structures. Indentation loading between 50 and 500 kN induced tensile strengths that ranged between 675–1050 and 390–810 MPa on the prismatic and nacreous layers, respectively. In addition, the morphology of the shell surface exhibited an interlocking structure with a large surface for binding to the organic matrix. The observed reinforcement of the shell explained the hardness property of the shell. The improved hardness of the shell implies that it can be beneficiated into filler that may be used to improve the mechanical properties of polymeric composite materials.

The Heart Rhythm of the Giant African Snail Achatina Fulica of Different Ages when Feeding

The Heart Rhythm of the Giant African Snail Achatina Fulica of Different Ages when Feeding

Traditional knowledge of invertebrates used for medicine and magical\u2013religious purposes by traditional healers and indigenous populations in the Plateau Department, Republic of Benin

BackgroundSince ancient times, invertebrates have played an important role in the traditional medicine in many parts of the world. In south-eastern Benin, more specifically in the Plateau Department, invertebrates are widely used in folk medicine. However, studies on their therapeutic use has been neglected and their magical–religious purposes are poorly understood. The present study aims to document traditional knowledge related to the use of invertebrates for medicinal and magical–religious purposes by traditional healers and indigenous people of Plateau Department.MethodsAn ethno-sociological survey was conducted with 145 informants (80 traditional healers, 12 merchants of medicinal animals and 53 households) belonging to six ethnic groups, in 20 villages located in Plateau of Benin. Data were collected through the participatory rural appraisal method involving individual interviews and direct observations with semi-structured questionnaires. The collected data regarding various medicinal and magical–religious uses of invertebrates were analysed through informant consensus factor (ICF), use value (UV) and, fidelity level (FL).ResultsA total of 20 families and 38 species of invertebrates, distributed among 6 taxonomic categories, were found to be used to treat 50 different ailments. Insects occupied 64.7% of the total invertebrates listed. The African earthworm Eudrilus eugeniae K. and African giant snail Achatina achatina L. had the highest use values. The highest ICF value (1.0) was cited for diseases of the blood or blood-forming organs. A principal component analysis (PCA) revealed the influence of ethnic groups in the diseases treated with invertebrates. The highest FL (100%) was recorded for 12 invertebrate species treating various ailments. Most of invertebrate-based remedies were associated with plant species. The mode of administration was mainly oral and topical. Most of the invertebrate drugs were traditionally collected in nature or imported, mainly from Nigeria. In addition, 7 magical–religious practices are documented.ConclusionsOur results reveal that several invertebrate species play an important role in healing practices and magical–religious rituals in the Plateau Department. We suggest further studies to confirm the presence of any bioactive compounds on invertebrate species use in traditional medicine. In addition, this study highlights the need for ecological investigations of these species, in order to develop strategies for their conservation and sustainable use.

Psychotria microphylla induces oxidative stress and biochemical alterations in giant African land snail Achatina achatina (Linnaeus, 1758)

Psychotria microphylla is an ichthyotoxic botanical used to stupefy fish prior to harvesting in aquatic systems. The current study investigated the effect of P. microphylla leaf extract on the oxidative stress and biochemical parameters of the giant African land snail, Achatina achatina. Adult A. achatina were administered 0.35, 0.45 and 0.55 mg l−1 leaf extract of P. microphylla and sampling was done after 24, 48, 72 and 96 h durations. Oxidative stress was evident by the significant increase in lipid peroxidation (LPO). Maximum LPO values of 36.13% and 63.69% were observed in A. achatina administered 0.55 mg l−1 of the leaf extract at 24 h and 96 h respectively. Superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) significantly decreased, whereas the values of glutathione reductase (GR) increased significantly compared to the control. Extract-induced toxicity was evident by the significant increase in alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activity relative to the control. The current findings indicate the potential toxicity of P. microphylla and suggest that it could be used for control of terrestrial snail pests.

A chromosomal-level genome assembly for the giant African snail Achatina fulica.

Background Achatina fulica, the giant African snail, is the largest terrestrial mollusk species. Owing to its voracious appetite, wide environmental adaptability, high growth rate, and reproductive capacity, it has become an invasive species across the world, mainly in Southeast Asia, Japan, the western Pacific islands, and China. This pest can damage agricultural crops and is an intermediate host of many parasites that can threaten human health. However, genomic information of A. fulica remains limited, hindering genetic and genomic studies for invasion control and management of the species.FindingsUsing a k-mer–based method, we estimated the A. fulica genome size to be 2.12 Gb, with a high repeat content up to 71%. Roughly 101.6 Gb genomic long-read data of A. fulica were generated from the Pacific Biosciences sequencing platform and assembled to produce a first A. fulica genome of 1.85 Gb with a contig N50 length of 726 kb. Using contact information from the Hi-C sequencing data, we successfully anchored 99.32% contig sequences into 31 chromosomes, leading to the final contig and scaffold N50 length of 721 kb and 59.6 Mb, respectively. The continuity, completeness, and accuracy were evaluated by genome comparison with other mollusk genomes, BUSCO assessment, and genomic read mapping. A total of 23,726 protein-coding genes were predicted from the assembled genome, among which 96.34% of the genes were functionally annotated. The phylogenetic analysis using whole-genome protein-coding genes revealed that A. fulica separated from a common ancestor with Biomphalaria glabrata ∼182 million years ago.ConclusionTo our knowledge, the A. fulica genome is the first terrestrial mollusk genome published to date. The chromosome sequence of A. fulica will provide the research community with a valuable resource for population genetics and environmental adaptation studies for the species, as well as investigations of the chromosome-level of evolution within mollusks.

Genetic characterization of Angiostrongyluslarvae and their intermediate host, Achatina fulica, in Thailand.

Angiostrongyliasis is a parasitic disease caused by nematodes of the genus Angiostrongylus. Distribution of this worm corresponds to the dispersal of its main intermediate host, the giant African land snail Achatina fulica. Genetic characterization can help identify parasitic pathogens and control the spreading of disease. The present study describes infection of A. fulica by Angiostrongylus, and provides a genetic outlook based on sequencing of specific regions. We collected 343 land snails from 22 provinces across six regions of Thailand between May 2017 and July 2018. Artificial digestion and Baermann's technique were employed to isolate Angiostrongylus larvae. The worm and its intermediate host were identified by sequencing with specific nucleotide regions. Phylogenetic tree was constructed to evaluate the relationship with other isolates. A. fulica from Chaiyaphum province was infected with A. cantonensis, whereas snails collected from Phrae and Chiang Rai provinces were infected with A. malaysiensis. The maximum likelihood tree based on 74 A. fulica COI sequences revealed monophyletic groups and identified two haplotypes: AF1 and AF2. Only AF1, which is distributed in all regions of Thailand, harbored the larvae of A. cantonensis and A. malaysiensis. Two mitochondrial genes (COI and cytb) and two nuclear regions (ITS2 and SSU rRNA) were sequenced in 41 Angiostrongylus specimens. The COI gene indicated that A. cantonensis was closely related to the AC10 haplotype; whereas the cytb gene revealed two new haplotypes: AC19 and AC20. SSU rRNA was useful for the identification of A. cantonensis; whereas ITS2 was a good genetic marker for differentiating between A. cantonensis and A. malaysiensis. This study provides genetic information about the parasite Angiostrongylus and its snail intermediate host. The data in this work may be useful for further study on the identification of Angiostrongylus spp., the genetic relationship between intermediate host and parasite, and control of parasites.

Mucous cell distribution and mucus production during early growth periods of the giant African snail (Achatina fulica)

The giant African snail (Achatina fulica) secretes mucus for crawling and protection from moisture loss and pathogenic infections. The snail mucus has been popularly used as a bioactive reagent in medical and cosmeceutical products. This study observed the distribution of pedal mucous cells of A. fulica and the snail growth effect (1–3 mth) on pedal mucus production and the types of mucous cells. Foot tissues were processed using a paraffin technique and stained with Masson’s trichrome, periodic acid Schiff, and periodic acid Schiff-Alcian Blue at pH 2.5. Visualization under a light microscope showed that the pedal mucus of A. fulica was mainly produced from two types of mucous glands: 1) tubular mucous gland cells located on the dorsal part of foot that produced acid mucopolysaccharide mucus; and 2) round mucous gland cells located on the ventral part of foot that produced acid and neutral mucopolysaccharide mucus. A positive correlation between the acid mucin level and snail age was only observed on the dorsal area. The level of neutral mucin from both sides was highest after 2 mth. The average length of the mucous cells on the dorsal surface significantly increased during growth. This study revealed the change and distribution of the mucous cells in early A. fulica development to inform further applications in snail bioactive compounds.

O caracol-gigante-africano Achatina fulica (Bowdich, 1822): análise do conteúdo em livros didáticos de ciências e biologia indicados pelo programa nacional do livro didático (PNLD) 2017 e 2018

Verificou-se a presença de conteúdos sobre o caracol-gigante-africano Achatina fulica nas coleções de Ciências e Biologia indicados pelo PNLD 2017/2018, quanto a presença de imagens e informações referentes à transmissão de doenças, e alertas sobre manejo e controle da população dessa espécie exótica invasora. Os resultados revelaram a ausência de qualquer menção sobre o molusco em 50 % das coleções de Ciências e em 30 % das coleções de Biologia, omissões/incorreções em conceitos e imagens, e algumas legendas equivocadas nos conteúdos encontrados. Concluiu-se que há necessidade de maiores cuidados na elaboração dessas coleções ao tratar de temas de interesse à saúde pública e ao meio ambiente, pois informações corretas contribuem na construção do conhecimento e na formação de atitudes que minimizam o risco de se contrair doenças além de evitar a frequente confusão entre o Achatina fulica e o molusco nativo Megalobulimus sp ameaçado de extinção.

First record of body colour polymorphism in giant African snail Achatina fulica (Bowdich, 1822) - a comparative study using mitochondrial cytochrome oxidase subunit I (COI) gene

The presence of the body colour polymorphism in the tropical invasive pest giant African snail is reported for the first time from South India. Three different body colour polymorphs were recognised viz. grey, black and white. The grey body colour is the most common polymorph. The black and white colour polymorphs are found to be in almost equal proportions in the reported localities with the grey counterparts. The cytochrome oxidase subunit I (COI) sequences of the three colour polymorphs are found to be identical. The presence of the body colour polymorphism in south India may be attributed to the avian predation and other selection pressures.

Occurrence of Rhabditid Nematodes in the Pet Giant African Land Snails (Achatina fulica).

Gastropods comprise nearly 60,000 species of aquatic as well as terrestrial mollusks, primarily snails and slugs. The giant African land snail (Achatina fulica) is one of the most popular pet snails worldwide. This gastropod mollusk is known as the intermediate host of several parasites that cause severe diseases in pets, free-ranging vertebrates, and humans. The aim of this survey was to investigate the occurrence of parasites in giant African land snails kept as pets in southern Italy. Fresh fecal samples were collected from a total of 60 giant African land snails kept in three private collections in Campania region (Italy). In addition, microscopic analysis of mucus and histological examination of biopsy samples from the foot muscle of 30 individual snails were performed. Coprological examination revealed the presence of rhabditid nematodes identified by both morphological and molecular assessment as Rhabditella axei in two out of three examined samples, and Rhabditis terricola, Cruznema sp., and Pristionchus entomophagus in one coprological sample. No parasites were detected in the muscle biopsy samples, or in the mucus. Due to the potential harm of rhabditid nematodes, their presence in giant African land snails potentially in contact with both pets and humans should not be disregarded.

Optimization and characterization of polysaccharides extraction from Giant African snail (Achatina fulica) using pressurized hot water extraction (PHWE)

Achatina fulica was treated by pressurized hot water to extract bioactive polysaccharides and the extraction process was optimized with the extraction yield by response surface methodology (RSM). The optimized condition was temperature of 133.53 °C, water to solid ratio of 54.11 mL/g, and time of 14.95 min, and the yield of the polysaccharide was 42.39% ± 0.85%. The characterization of polysaccharide was comprised of preliminary, physical, and structural properties by GAG, uronic acid, and sulfate content, TLC, HPLC, GPC, FT-IR, UV–Vis spectroscopy, TGA, and XRD. The snail hydrolysis polysaccharides (SPs) was also demonstrated to its antioxidant by ABTS+ assay and total antioxidant activity of 32.30% ± 0.31% and 584.12 μg ± 2.10 μg ascorbic acid equivalent (AE)/L. This study indicated that pressurized hot water extraction can be used to extract polysaccharides from A. fulica.

Perception of giant African snail (Achatina fulica) in urban community from Colombia

In Colombia, the control of giant African snail populations (Achatina fulica) has been enforced for the past eight years according to the Environmental, Housing, and Territorial Development Ministry (MAVDT from its initials in Spanish). During this period, the environmental authorities have carried out a series of campaigns for snail eradication and to raise awareness in the general community to involve it in the control of this invasive species. In order to inquire about the perception of the citizens of Cali, Colombia, have of the giant African snail and their role as primary stakeholders in the local control programs, a structured survey was done, and the dependency on the sociodemographic characteristics was established through Fisher’s exact test. 316 people took part in the survey; over 80% of the individuals recognized the giant African snail and their form of control, but over 90% of them did not participate in the control campaigns. The perception of the giant African snail varied noticeably with the respondents’ age and was independent of socio-economic and educational level. In conclusion, it was detected a solid dissociation between people and the actions carried out by the environmental authority. It is recommended to take into account people’s concept of invasive species control in other cities as a fundamental instrument in the construction of a more dynamic and inclusive control model.

Registro de melanismo en el gavilán pico gancho (Chondrohierax uncinatus uncinatus), con una nota de depredación sobre el caracol africano (Achatina fulica) al sur de Ecuador

Describo el registro poco común de un individuo melánico de gavilán pico gancho (Chon­drohierax uncinatus uncinatus) en el sur de Ecuador. Además documento la depredación del caracol gigante africano (Achatina fulica). Refiero la manipulación del caracol, su extracción de la concha y deglución mientras el individuo posaba en una rama de árbol (Triplaris cumingiana), rodeado de cultivos de cacao (Theobroma cacao). Además, alrededor del sitio de avistamiento registré cinco conchas de caracol gigante africano con perforaciones atribuibles al gavilán pico gancho. Este registro confirma su presencia dentro de la provincia y adiciona un caso de eumelanismo en Ecuador. Sugiero al gavilán pico gancho como un controlador biológico del caracol africano.

Purification and characterization of phytase from Aspergillus fumigatus Isolated from African Giant Snail (Achatina fulica)

Abstract Phytase, an enzyme that catalyzes the stepwise hydrolysis of phytate into phosphorous and organophosphate compound and capable of reducing environmental pollution and metal chelating effect of phytate was purified from Aspergillus fumigatus isolated from African Giant Snail (Achatina fulica). The crude phytase was subjected to ammonium sulphate precipitation, DEAE Sephacel and Sephacryl S-200. Physicochemical parameters of the enzyme were investigated. Approximately 45%- fold purification was achieved with an overall recovery of 15%. The purified phytase had optima temperature and pH activity at 40 °C and pH 6 respectively with a marked activity of 83% and 78% at pH 8.0 and 9.0 respectively. It retained over 80% of its initial activity after 6 h at pH 4.0 − 7.0 with a 48% remaining activity at 50 °C after 1 h incubation time. Vmax and Km were determined to be 35.7μmol/min and 7.2 mM respectively. The phytase activity was enhanced in the presence of Ca2+, Cu2+ and Fe2+, but was greatly inhibited by Zn2+, Hg2+, Al3+, sodium dodecyl sulphate (SDS) and urea. The results showed that phytase produced from A. fumigatus may contribute significantly to the phytate degrading enzyme system in African giant snail and may serve a useful commercial purpose.

Management of Achatina fulica (Bowdich, 1822) (Pulmonata: Achatinidae) in lettuce (Lactuca sativa L.)

ABSTRACT: The giant African snail Achatina fulica was introduced in Brazil and since then has become an important pest, because of its resistance to abiotic conditions, hermaphroditism, polyphagia, and absence of natural predators. This study aims to evaluate the control of A. fulica in lettuce, in Alagoas, Brazil. Bioassays for the determination of lethal dose and lethal time to adults of A. fulica and the egg mortality were performed in the laboratory by applying commercial synthetic products, commercial and non-commercial alcoholic botanical extracts on mollusk adults. Additionally, the protein concentration, lipase activity and enzyme acetylcholinesterase (AChE), and butyrylcholinesterase (BuChE), in the stomach, intestine, nervous ganglion and liver were determined. The alcoholic extract of Capsicum frutescens caused higher mortality of A. fulica, and the alcoholic extract of C. frutescens and Piper tuberculatum oil can prevent the hatching of A. fulica. The lipase activity was present and in greater quantities in tissues, stomach, intestine, liver and ganglia of A. fulica, before and after exposure of the alcoholic extract of C. frutescens. The enzymatic activity of BuChE was present in the ganglia and liver of A. fulica, prior to exposure of the alcoholic extract of C. frutescens. The enzymatic activity of AChE was present only in the ganglion and absent in liver of A. fulica, prior to exposure of the alcoholic extract of C. frutescens. The concentration of 10% of the alcoholic extract of C. frutescens caused 84% mortality of adult A. fulica in lettuce in field conditions.

Population fluctuation and food preference of African snail by horticulture crops

ABSTRACT: The African snail Achatina fulica (Bowdich, 1822), originally from Africa, was introduced in Brazil and since then became an important pest, because of its resistance to abiotic conditions, hermaphroditism, polyphagia and absence of natural enemies. Considered as one of the 100 worst pests in the world, with the record of establishment in almost all Brazilian states, it causes sanitary, ecological and economic losses. In this context, the objective of this study was to determine the population dynamics and food preference of the giant snail in three areas of lettuce, located in Alagoas, Brazil. There was no statistical difference between food preference tests with and without choice among the varieties offered. To the fluctuation of the population of A. fulica, the Pearson correlation coefficients were negative only for temperature, and there was no correlation with precipitation and relative humidity.

Achatina fulica (Mollusca: Achatinidae) Naturally Infected with Caenorhabditis briggsae (Dougherty and Nigon, 1949) (Nematoda: Rhabditidae).

Specimens of the African snail Achatina fulica, collected in Bucaramanga, Colombia, were examined for parasites. Numerous specimens of Caenorhabditis briggsae were collected from the digestive tract of the snails and identified by the structure of male spiculum, caudal bursa, gubernaculum and precloacal lip in males, triangular tooth in metarhabdion, and protandrous hermaphrodites with a female:male ratio of 15:1 and with morphometry. DNA sequences of the ITS2 region of the ribosomal gene array from worms in this study matched with 99% similarity to published sequences of C. briggsae. A redescription of the species is provided. This is the first record of the species in South America.

MOLLUSCS: THEIR USAGE AS NUTRITION, MEDICINE, APHRODISIAC, COSMETIC, JEWELRY, COWRY, PEARL, ACCESSORY AND SO ON FROM THE HISTORY TO TODAY

Present study has evaluated the usage and properties of the mollusc phylum from the history to today. Many types of molluscs are eaten worldwide, either cooked or raw due to their rich nutritional value. Furthermore, they are used as pearls, cowry and accessory materials, for tools like household dishes, cooking pots and utensils such as spoon, cutlery, scoops, spatulas, etc. Some of them are destructive and caused ecological damage, some serve as intermediate hosts for human parasites; some can cause damage to crops. Mollusc meat is known to be highly nutritious and salutary owing to its high content of essential amino acids, proteins, fatty acids, vitamins and minerals. In addition, some of the bioactive compounds including antiviral, antimicrobial, antiprotozoal, antifungal, antihelminthic and anticancer products are producing by molluscs. The largest edible snail is African land snail Achatina achatina mostly consumed by African people. Molluscs were very prominent dishes during the Roman Empire due to their aphrodisiac effect. Some mollusc species include zinc and essential amino acids which keeping up body energy and boost sex drive as aphrodisiac, arrange immune system and makes bones stronger. Pearls are highly esteemed bivalve products containing nacreous deposit composed of 82 - 86% calcium carbonate (aragonite crystals), 10-14% organic substance conchiolin and 2-4% water. Cowry is a marine snail from genus Cypraea dwelling on mostly in coastal waters of the Indian and Pacific oceans and used instead of money. Money cowry ( Cypraea moneta ), a 2.5cm yellow species, has served as currency in Africa.

Antimicrobial Susceptibility Profile of Microorganisms Isolated from the Intestine and Body Parts of the African Giant Land Snail (Achatina achatina) Sold in Akure, Nigeria

Antimicrobial Susceptibility Profile of Microorganisms Isolated from the Intestine and Body Parts of the African Giant Land Snail (Achatina achatina) Sold in Akure, Nigeria