African Land Snail Research Articles

Biochemical and microbiological properties of haemolymph from African land snail (Achatina achatina) in Akure metropolis

Haemolymphs were aseptically collected from matured African Land Snails (Achatina achatina) obtained from four villages in Akure metropolis and examined for biochemical and microbiological properties using standard methods. Four villages (Ibulesoro, Aule, Igoba and Oda) within Akure metropolis were purposefully selected for this study, Twenty (20) snails were obtained in each village and a total of eighty (80) snail samples were collected from the four villages. The results of biochemical constituents of the haemolymph revealed that the mean values of pH ranged from 6.68 - 6.97; total protein (mg/dl) 24.27 - 30.33; glucose (mg/dl) 13.94 - 19.33; lipid (mg/L) 1.38 – 1.71; urea (g/dl) 3.63 – 3.92; albumin (g/dl) 1.74 – 1.96 and globulin (g/dl) 3.13 – 3.52. Mineral components of the haemolymph from the snails in all locations revealed the concentration (mg/L) of sodium in the ranged of 138.02 – 209.54; calcium 30.63 – 38.01; phosphate 54.36 – 65.74; potassium 32.15 – 40.22; bicarbonate 21.08 – 27.31; magnesium 16.41 – 21.52 and chloride 83.07 – 118.92. The results of microbiological components of the haemolymph from the snail samples revealed the mean plate count of various bacterial and fungi isolate. The amount (cfu/ml) of bacterial isolates in the haemolymph are Staphylococcus aureus which ranged from 1.92 x 103 – 2.86 x 103; Faecal strephtoccoci 2.48 x 103– 4.26 x 103 and Shigella dysentriae 0.83 x 103– 2.23 x 103; others include Pseudomonas aeroginosa, Bacillus spp, Escherichia coli and Klebsiella pneumonia. The predominant fungi isolate in the haemolymph was mucor spp with the mean total count ranged from 4.31 x 103– 9.33 x 103; followed by Aspergilus fumigatus 3.21 x 103– 5.43 x 103 , others are Rhizopus spp, Aspergillus flavus, and Aspergillus niger. The study revealed that the snail fluid (haemolymph) contained adequate amount of biochemical components and nutritionally valuable minerals such as sodium, potassium, calcium and other ions that could enhance the body normal physiological function when consumed. However, the prevalent of some pathogenic bacterial and fungi in the haemolymph proof it to be unsafe for human consumption in its raw form. The study therefore suggest that the haemolymph should be adequately pasteurized and disinfect before consumption as herbal remedies for medicinal purpose.

Biochemical and microbiological properties of haemolymph from African land snail (Achatina achatina) in Akure metropolis

Biochemical and microbiological properties of haemolymph from African land snail (Achatina achatina) in Akure metropolis

Production performance of Giant African Land Snails (Archachatina marginata) at the Sudano-Guinean highland zone of Cameroon

A study on the production performance of Giant African Land snails was carried out within the Joint Initiative Group of Agro-pastoral Producers United Hands of Foungwo-Santchou (CIG-PAMUFOSA). The general objective of this study was to contribute to a better knowledge of the production performance of the Giant African Land Snail in captivity in Cameroon. For this purpose, the snails were monitored for two months and data on growth and reproductive performance were collected. Growth parameters were estimated from 183 snails aged between 6 and 8 months as a starting number. The results obtained show that the average daily weight gain was 0.06 ± 0.07 g and the shell length and diameter gain was 0.0019 ± 0.0077 mm/day and 0.016 ± 0.0012 mm/day, respectively. Food intake was 1.86 ± 0.17 g/day with a consumption index of 25.87 ± 2.60 and a mortality rate of 40%. Reproductive characteristics were estimated a starting number of 1095 adult snails aged between 1.5 and 2.5 years as it appears that the age at sexual maturity was greater than or equal to 11 months of age. For an average breeding weight of 93.09 ± 25.03 g, they produce clutches averaging 5.66 ± 1.80 eggs per clutch with an average weight of 8.18 ± 3.30 g. The weight of an egg was 1.44 ± 0.35 g, the individual large and small diameter of the eggs were 14.97 ± 1.45 mm and 11.28 ± 1.13 mm, respectively. The incubation period was 35.62 ± 8.16 days and hatching percentage was 76.08%. The factors influencing reproduction and growth performance of Giant African Land Snail would be: housing conditions (high density, breeding substrate), incubation condition, feed quality, and neglect. For an improvement in production performance on this farm, it would be wise to feed the animals with concentrated feed and to follow the strict standard guidelines regarding stocking density.

Parasitism of terrestrial gastropods by medically-important nematodes in Brazil.

An ample variety of parasitic associations are found between mollusks and nematodes, in which the mollusks may act as intermediate, paratenic or definitive hosts. Some free-living nematodes, in particular those of the order Rhabditida, are also found frequently in terrestrial mollusks. The present study reviews the results of the parasitological testing on samples of terrestrial mollusks conducted at the Brazilian National Reference Laboratory for Schistosomiasis and Malacology between 2008 and 2021. The samples were supplied primarily by the public health authorities from the different regions of Brazil, but also by research institutions and general population. The mollusks were processed individually and the obtained larvae were identified from their morphology and, whenever necessary, by molecular analysis. A total of 1,919 service orders were registered during the period, including 19,758 mollusk specimens collected from 23 of the 26 Brazilian states, as well as the Federal District, totalizing 145 municipalities. There was a marked predominance of the synanthropic species that are widely distributed in Brazil-Achatina fulica (87.08%), Bulimulus tenuissimus (4.18%), Bradybaena similaris (2.06%), and Sarasinula linguaeformis (1.50%). Of the 16,750 terrestrial mollusks examined, nematodes were recorded in 1,308 service orders, with the predominance of the superfamily Metastrongyloidea, in 616 service orders. They included Angiostrongylus cantonensis, rat lungworm, which was found in 252 samples, and Aelurostrongylus abstrusus in 145 samples. Free-living nematodes were found in 952 samples, Ancylostoma caninum and Cruzia tentaculata (previously identified as Strongyluris sp.) in one and 275 samples, respectively, and other parasites in 210 samples (not identified). The results highlight the diversity of the associations between nematodes and terrestrial mollusks in Brazil, in particular invasive and synanthropic species, with emphasis on the giant African land snail, Achatina fulica. They demonstrate the prominent role of this species of mollusk in the transmission of medically-important nematodes, which affect the health of both humans and animals, in particular eosinophilic meningitis, which is caused by Angiostrongylus cantonensis. This reinforces the need for more studies, and justify the growing demand for information as well as parasitological diagnosis of this mollusk, given its wide distribution in Brazil and its impact as an urban pest.

Evaluation of the Reproductive Performance, Body Proportions, Nutritional Value, and Biochemical Parameters of Achatina achatina

To assess the effect of energy levels on the reproductive performance of African Land Snails, ninety young snails of one month of age, weighing between 1 and 1.5 g, of shell length between 15.5 and 23.85 mm and shell diameter between 12.60 and 16.85 mm and free from wounds or shell defects were divided into 3 groups of 5 snails each and 6 replicates in cages equipped with feeders and drinking troughs. Each treatment was randomly assignedto one of the experimental feeds with variable energy levels (2600, 2800, and 3000 kcal/kg) in addition to pawpaw leaves as a staple feed. The cultured substrates were watered daily, and the animals were monitored for a period of 24 months. The results showed that the shortest ages of onset of maturity as well as the highest number of spawns per treatment were observed in snails receiving 2600 kcal/kg of energy in the feed compared to other treatments. The highest egg morphometric and fertility characteristics were found in animals fed the highest energy level of the feed. The highest protein level in the hemolymph was observed in snails given 3000 kcal/kg energy of the feed while the lowest cholesterol level was observed in animals receiving the same treatment. The highest total meat and gonad weight were observed in animals receiving 2800 kcal/kg energy in the feed compared to other treatments. The levels of dry and organic matter, protein, and fat in the ash increased with the energy level of the diet. Animals that received 2800 kcal/kg energy in the diet recorded a significantly lower calcium level in the flesh compared to the other two treatments. On the other hand, the percentage of phosphorus increased significantly with the energy level of the diet. In conclusion, the 2600 kcal/kg energy level can be retained in the feed of adult snails.

Nutritious food and health risks: a review on the edible land snails of Africa

Snail meat is a source of food and livelihood for many inhabitants especially in sub-Saharan Africa. They are consumed in households or traded at local and international markets. However, African land snails are rarely farmed but picked from environments that include decaying vegetation, soil debris, and untreated human and household wastes. These ‘snail natural habitats’ may contain microbial pathogens that could easily be ingested by snails and transmitted to snail meat handlers and consumers. The objective of this study was to investigate published information that establishes the local consumption practices of African land snails as a credible source of foodborne infections. Acknowledging the nutritional benefits of consuming snails, this research revealed local practices in snail gathering, handling, preparation and preservation could significantly contribute to foodrelated disease burdens to Africans and several African snail meat-exporting countries. With this, national and international food safety regulations are required for African snail meat consumption.

Fine-scale geographical sampling and molecular characterization of the giant African land snail in its invasive range in Asia shows low genetic diversity, new haplotypes and the emergence of another haplotype from the Indian Ocean Islands

Abstract Native to East Africa, the giant African snail Lissachatina [=Achatina] fulica (Bowdich, 1822) is a tropical crop pest and one of the world’s top 100 invasive species. It is now present in at least 52 countries worldwide, with an actively expanding range. Lissachatina fulica was first introduced to India in 1847, but subsequent arrivals in India and local patterns of spread remain unclear. This study uses the 16S rRNA gene to identify the extent of genetic variation in India by sampling Indian populations and comparing them with published sequence data. A total of 307 snails were collected from 178 localities in India and from a single locality in the UAE, and the 16S rRNA gene was amplified and sequenced. Eight haplotypes were identified from India of which four are newly recognized. The new haplotypes identified in this study have increased the number of L. fulica 16S rRNA haplotypes from 19 to 23. Examination of haplotype and nucleotide diversities revealed that genetic variation is low in India, the UAE and across Asia as a whole. The number of haplotypes was higher in India when compared to other invasive regions but all of the Asian haplotypes appear to be closely related to the most common haplotypes in the Indian Ocean Islands. Heavy trade between the snail-infested and native-range countries suggests that the variation observed in India might be traced back to its native range, but the lack of sampling and paucity of sequences from East Africa currently prevents a comparison. Tracing back the emergent haplotypes by additional sampling could throw more light on the spread of L. fulica.

Extraction and Identification of Bioactive Compounds from Archachatina marginata (Giant African Land Snail).

Extraction and Identification of Bioactive Compounds from Archachatina marginata (Giant African Land Snail).

Public Health Risk of Foodborne Pathogens in Edible African Land Snails, Cameroon.

In tropical countries, land snails are an important food source; however, foodborne disease risks are poorly quantified. We detected Campylobacter spp., Yersinia spp., Listeria spp., Salmonella spp., or Shiga-toxigenic Escherichia coli in 57%–86% of snails in Cameroon. Snail meat is a likely vector for enteric diseases in sub-Saharan Africa countries.

Immunological indices of Giant African Land snails (Archachatina marginata) improved with fixed dose of vitamin C during acute heat stress

The study determined immunological indices of Giant African Land snail (Archachatina marginata) improved with fixed dose of vitamin C under acute heat stress (AHS). Prior to the AHS, vitamin C was administered for four weeks to two treatment groups, while other two treatment groups were not. Each treatment was monitored, haemolymph collected at 0, 30 and 60 minutes exposure times. Immunological cytokines: interferon gamma (IFN-γ) and interleukin 2 (IL-2); and total haemocyte counts (THC) were determined. Under AHS, vitamin C elevated (p <0.05) IFN-γ production (606.33 ± 302.86) compared to other groups with or without vitamin C administration (7.20 ± 1.58 vs. 73.20 ± 32.23 vs. 7.80 ± 1.36). IL-2 was not affected (p >0.05) by vitamin C under AHS. Highest (p <0.05) THC values was obtained with vitamin C administration under AHS, but reduced under no AHS. Exposure time affected (p <0.05) IFN-γ production and THC values, but not IL-2 (p >0.05). With fixed dose of vitamin C and exposure time, highest (p <0.05) IFN-γ values were obtained under AHS with vitamin C administration at 30 minutes and at 60 minutes in THC, compared to other groups. The study concluded that fixed dose of vitamin C at 150 mg kg-1 of feed was appropriate under AHS to boost the immune system of the animals.

Waste leachate induces histological alterations in Limicolaria aurora (Jay, 1839) digestive gland

Unsanitary open dumping and burning of wastes in dumpsites results to constant leaching of waste pollutants into the surrounding environment with attendant harmful consequences on wildlife and public health. Here, we investigated the histological effects of Onitsha municipal waste leachate on the Giant African land snail, Limicolaria aurora (Jay 1839). The histopathological effects of waste leachate on the digestive cells of the snails were examined following standard protocols. Snails were exposed to different concentrations (0, 6.25, 12.5, 25.0 and 50.0%) of the leachate for a total duration of 21 days. Histological results obtained showed that waste leachate caused dose and duration dependent alterations in the digestive glands of L. aurora. Obvious histological variations were observed in snails exposed to 50% concentrations of the leachate compared to other doses. Observed histological changes were mainly degeneration of the digestive tubules, fragmentation and disappearance of the digestive cells, marked increase in excretory cells, necrosis and epithelia sloughing. This study therefore highlights the potential toxicity of waste leachate of causing mild to severe damage in the tissues of organisms. Reinforcing the fact, that waste leachate contains a mix of toxic substances that could pose a severe injury to the biological system of surrounding biota, including humans.

POST AESTIVATION DYNAMICS OF THE FEMALE REPRODUCTIVE ORGANS OF GIANT AFRICAN LAND SNAILS (ARCHACHATINA MARGINATA): HISTOLOGICAL AND HISTOCHEMICAL PERSPECTIVE

The study was carried out to monitor the recovering of the tissue of the female reproductive organs of Giant African Land Snail (Archachatinamarginata) (GALS) post aestivation. The histological and histochemical changes were examined at 0, 3 and 6 weeks of post aestivation. The experiment was conducted using forty (40) reproductively matured and apparently healthy snails, laid out in a completely randomized design, with 2 snails replicated four times. The histological and histochemicalsections were observed for tissue structural alteration, lipid, calcium and glycogen accumulation (or depletion) with H & E, Von Kossa and PAS staining techniques respectively. Prominent basement membrane with underlying supportive tissue was observed at the 6th week aestivation lengths. At the 3rd week of arousal, there were clearer lumen and mass of densely packed cells around the epithelium. The emergence of secretory epithelium cells were also observed at the 3rd week post dormancy. The control showed cells which were sparsely packed, oblique with a diminished structural conformation. At arousal, circular or pear shaped follicles were observed in the tissue of the albumin gland with conspicuous glandular cells and appearance of lumen. The follicles got progressively enlarged with rehydration (3P – 6P), closing up the intercellular spaces. The vagina showed a diminished lumen prominently lined with ciliated columnar epitheliumwith outstanding muscular walls which did not show substantial recovery within the investigated arousal periods. The Albumin gland tissues of Archachatinamarginata were positive for glycogen deposition. Intracellular storage form of carbohydrate (glycogen) was marginally evident in the 6th week aestivation section. On arousal, substantial improvement was not observed within the post aestivation period.

POST AESTIVATION DYNAMICS OF THE MALE AND HERMAPHRODITIC REPRODUCTIVE ORGANS OF GIANT AFRICAN LAND SNAILS (ARCHACHATINAMARGINATA): HISTOLOGICAL AND HISTOCHEMICAL PERSPECTIVE

The male reproductive organs and hermaphrodite ducts of the Giant African Land Snail (Archachatinamarginata) were examined histologically and histochemically at 0, 3 and 6 weeks post aestivation. The transverse section of the tissue of little hermaphrodite duct aestivated for 6 weeks (control) resulted in clear, wide and highly branched lumen lined with ciliated cuboidal epithelium. The post aestivation section at the 3rd week did not differ substantially. At the 6th week post aestivation, the muscular wall took a wavy and more branching appearance. The common hermaphrodite duct revealed a conspicuous intercellular spaces and sparse composition of the cellular components. The lumens were inflated with thick peripheral walls. The post aestivation sections tended toward recovery with much cellular prominence with discernible boundaries. The vas deferens generallyappeared organized with respect to segmentations and arrangement in the control. Adherence of cell mass and granules were typical features of the 6th week aestivated tissue. At arousal, these features diminished with farther dispersed cells and loosed connective tissues. Thepenis displayed multiplied and larger cell mass with clear lumen and increasing peripheral thickness. It can therefore be concluded that tissues of the male and hermaphroditic organs retained their firm conformation for six weeks dormancy period, Ca and lipid droplet regressed considerably. At arousal no substantial rejuvenation was attained 3rd week post aestivation but at the 6th week, adjustment toward reproductive preparation was observed with considerable calcium built up.

Nutritional Potential and Cost Implication of Yam Peel (Discorea Rotundata) as Ingredient for Growing Snails (Archachatina Marginata)

Yam peel is a fall out during processing of yam to pounded yam or yam flour and could be used as alternative means of energy in the nutrient of livestock. The aim was to know the consequence inclusion of dry yam peeling (YP) as substitute for maize in the diet of growing Giant African land snail on feed intake, weight gain, meat qualities and priced benefits. Yam peeled was substitute at 0% (YP1) Control, 25% (YP2), 50% (YP3) and 75% (YP4) as replacement for maize fraction in the nutrient of growing Giant African land snails. Each treatment was repeated thrice with 10 snails per replicate in a completely randomized design. Parameters taken or calculated were feed intake, weight gain, shell length and width, feed conversion ratio and priced per weight gain among others. Significant differences were observed in the mean total feed consumption of the snails fed inclusion levels of yam peel meal in the diets (P<0.05) The main total feed consumed of 544.32 g was taken in YP1, it was relatively similar to YP3 the mean lowest feed consumed of 516.46g was taken in YP4. The result of feed efficiency indicated that snails fed 0% YP as a substitute for maize fraction of the diet has most feed efficiency (P<0.05) and was not significantly different from YP3. The morbidity and mortality percent were very low in all the treatments. The main dressing percentage of 43.57% was taken in YP1 (P<0.05) it was not significantly different from 43.45 % and 43.13 % in YP2 and YP3 accordingly. Mean total no of egg laid was significantly influenced by different inclusion levels (p<0.05). From the study, it was revealed that weight gain, feed efficiency and dressing percentage were relatively similar in the snails fed zero percent diet and Fifty percent yam peel. The mean total number of egg laid and the size were not significantly different in the control and 50% inclusion, also the least cost per weight gain was recorded in YP3 containing 50% YP, hence maize fraction of the diet of snails could be substitute up to 50% of yam peel without any adverse effect.

Observations on the Digestive Enzymes in the Giant African Land Snails (Archachatina marginata): Significance and Prospects

Observations on the Digestive Enzymes in the Giant African Land Snails (Archachatina marginata): Significance and Prospects

Effect of replacing maize with plantain peels on the performance traits and haematological characteristics of African giant land snail

The study was carried out at the Niger Delta University, Faculty of Agriculture Teaching and Research Farm, Bayelsa State. A total of Ninety six (96) growing snails (Archachatina marginata). Using Plantain peel as an additive, four diets were formulated at the levels of 0%, 3%, 6%, and 9% to form the treatment diets. The experiment lasted for eight (8) weeks during which the weight gain, feed intake, shell width, shell length, shell thickness and hematological parameters were obtained. The weight gain, shell width, shell length and shell thickness are not significantly different (p<0.05) whereas, the feed intake differed significantly (p<0.05) for all the treatment diets in the experiment. From the results, it was concluded that concentrate with 0% inclusion of Plantain peel meal was suitable for snail diets as it gave the best performance. The hematological parameters measured in the African giant land snails are White blood cell, Neutrophile and Lymphocyte differed significantly (p<0.05). Plantain peel can serve as source of potassium for other animals, as the highest percentage of potassium was found in the hemolymph of snails fed with 9% inclusion of plantain peel. It is recommended that; there should be no inclusion of plantain peels in the diet of the African giant land snails in order to achieve higher weight gain and feed intake.

First report, morphological and molecular characterization of Caenorhabditis brenneri (Nematoda: Rhabditidae) isolated from the giant African land snail Achatina fulica (Gastropoda: Achatinidae)

First report, morphological and molecular characterization of Caenorhabditis brenneri (Nematoda: Rhabditidae) isolated from the giant African land snail Achatina fulica (Gastropoda: Achatinidae)

Achatina fulica (giant African land snail)

Achatina fulica (giant African land snail)

Effect of Calcium Source in Supplemental Diets on the Growth Performance and Carcass Characteristics of the Giant African Land Snails (<i>Archachatina marginata</i>) in the Western Highlands of Cameroon

To contribute to the diversification of protein sources, the conservation and preservation of the Giant African Land Snails (Archachatina marginata), a study was carried out between March and July 2019 at the Helvy Farms-WVED Cameroon located at Station Bamenda to investigate the effect of three calcium sources on their growth performance and carcass characteristics. 180 juvenile snails aged 4 months initially weighing between 24.2 and 28.5 g, shell length ranging between 40.25 - 48.35 mm, and shell diameter of between 14.08 - 18.44 mm were randomly allotted to 3 treatments containing each a different calcium source (crushed snail shell, eggshell and agricultural limestone) and a control treatment constituted of natural plant feeding materials of the snail. There were 45 snails per treatment, constituted of three replicates with 15 snails per replicate. Each replicate was housed in well-constructed surface trench pens equipped with drinking and feeding troughs. The basal diet made up of feedstuffs like pawpaw leaves and watermelons was provided ad libitum. The initial weights of the snails were recorded at the start of the experiment followed by weekly weight measurements, while the snail length and width were measured with a digital caliper of 0.05 mm accuracy. The snails were monitored for a period of 21 weeks and data was collected for 20 weeks after a 1 week adaptation period. The results showed that the weight gain (g) of snails for diets containing calcium sources in the supplemental diets were all significantly higher (P < 0.05) than the corresponding values recorded for the control diet with natural plant material. It was observed that the shell length (0.34 ± 0.02), shell width (0.16 ± 0.02), weight gain (13.13 ± 0.03) and feed conversion efficiency (1.977 ± 0.11) were highest in snails fed snail shell diet as calcium source compared with snails from other treatments. These values were however not significantly higher than corresponding values for the other two supplemental diets containing eggshell or agricultural limestone. It can be deduced that the snail shell is an important calcium source for growing snails and can be adopted and used in the diets of snails. This will amount to some good methods of recycling in snail production.

Assessing the efficacy of soapberry (Sapindus rarak) crude extract for controlling giant African land snail (Lissachatina fulica)

Assessing the efficacy of soapberry (Sapindus rarak) crude extract for controlling giant African land snail (Lissachatina fulica)