Infestation of cardamom by the invasive giant African land snail (Lissachatina fulica) in the Western Ghats, India

In 2007-2008, APHIS assisted in conducting capacity building workshops in Puerto Rico, Nicaragua, Guatemala, Honduras, Costa Rica, Colombia, Ecuador, Jamaica, and Trinidad. These were conducted in partnership with several private and public cooperators from the Region. The workshops emphasized the need to eliminate pests at the source of imported agricultural products, so that clean product arrives at the ports of entry of the importing country. In collaboration with the Inter-American Institute for Cooperation on Agriculture (IICA) two capacity building workshops on scale insects and mealybugs of economic importance were held; one in Barbados for Barbados and the Organization of Eastern Caribbean States(OECS), and the second in Jamaica for Jamaica, Trinidad and Tobago, the Dominican Republic, Bahamas, and Haiti. Between 2005 and 2008 APHIS assisted the Caribbean Region with surveys for the Red Palm Mite and the Giant African Snail. A USDA APHIS malacologist from the Academy of Natural Sciences in Philadelphia, PA, an entomologist from the APHIS Center for Plant Health Science and Technology (CPHST), and an acarologist from the USDA-ARS Systematic Entomology Laboratory in Beltsville, Maryland were assigned to upgrade the surveillance and pest identification skills of technical officers in the Caribbean Region. Financial assistance was provided for pest detection programs in Caribbean countries, in particular those targeted to Tephritid fruit flies, red palm mite, giant African land snail, and mealybugs. APHIS supported the Tephritid fruit fly trapping programme by providing trapping supplies to most countries in the region. APHIS cooperated with the Panama Ministry of Agriculture and the University of Panama to conduct plant pest surveys near the Panama Canal which is a major pathway for movement of commodities, and possibly plant pests, from Asia into the Greater Caribbean. The focus of these surveys has been on mealybugs, mites, wood borers and molluscs. APHIS provided support for regional meetings in the Caribbean concerned with the preparedness in the event the introduction of Highly Pathogenic Avian Influenza; these meetings resulted in the allocation of needed resources and strengthening safeguarding institutions in some countries. APHIS collaborated with CABI, CARICOM, CIRAD FAO and IICA in assembling Plant Health Directors of many Greater Caribbean countries with the objective developing coordinated programs to accomplish, in part, the desired outputs of the CISSIP proposal. In 2009 APHIS will continue its assistance to the Plant Health Directors Forum and the latter's technical working groups. APHIS helped implement the Caribbean Regional Diagnostic Network, a component of CISSIP, through the purchase of five state of the art internet connected distance digital diagnostic laboratory systems for deployment in five Caribbean countries.

The study on heavy metals concentrations in three species of terrestrial molluscs (land snails) in University of Calabar, Cross River State was carried out for a period of four months (August to November 2014). Three terrestrial molluscs namely: Achatina fulica, Achatina achatina and Archachatina marginata were used for the study. Snail samples were collected within University of Calabar Farm and along the shores of the Great Kwa River near University of Calabar Staff Quarters. Metals such as: Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb and Zn were analyzed after digestion using Graphite Furnace Atomic Absorption Spectrophotometer. Cd and Hg were Below Detectable Level (BDL) in the three species. Mean values of metal concentrations in Achatina fulica were: Co, 0.029±0.020mg/kg; Cr, 0.029±0.020mg/kg; Cu, 0.047±0.008mg/kg; Fe, 0.042±0.001mg/kg; Mn, 0.035±0.005mg/kg; Ni, 0.011±0.023mg/kg; Pb, 0.029±0.058mg/kg and Zn 0.047±0.005mg/kg. Mean values of metal concentrations in Achatina achatina were: Co, 0.030±0.021mg/kg; Cr, 0.028±0.019mg/kg; Cu, 0.043±0.004mg/kg; Fe, 0.043±0.002mg/kg; Mn 0.035±0.005mg/kg; Ni, 0.014±0.028mg/kg; Pb, 0.027±0.055mg/kg and Zn 0.043±0.012mg/kg. Mean metal concentrations in Archachatina marginata were: Co, 0.019±0.022mg/kg; Cr, 0.016±0.019mg/kg; Cu, 0.037±0.005mg/kg; Fe, 0.043±0.009mg/kg; Mn, 0.040±0.006mg/kg; Ni, 0.125±0.250mg/kg; Pb, 0.058±0.067mg/kg and Zn 0.046±0.012mg/kg. The concentrations of the metals did not vary statistically (p > 0.05) in the three species of molluscs, therefore were not statistically significant. Total rank score assessment showed that Archachatina marginata had the highest level of metals followed by Achatina fulica while Achatina achatina had the least concentrations, although the concentrations of metals in the three species were within the tolerance limits set out by WHO. Therefore consumption of snails picked within University of Calabar farm and along the shores of the Great Kwa River near University of Calabar Staff Quarters is recommended though continuous monitoring of these metals is necessary since metals can bio-accumulate in biological tissues over a period of time. Citation: Okorafor KA and Otielu P (2015). Concentrations of some metals in three species of terrestrial molluscs (Achatina fulica, Achatina achatina and Archachatina marginata) in bushes within University of Calabar, Calabar, Nigeria. Journal of Environmental Toxicology and Public Health 1(1): 25-29. Received October 20, 2015; Accepted October 26, 2015; Published November 4, 2015. Copyright: © 2015 Okorafor and Promise. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. JETPH is a journal publication of BRSF. Competing Interests: The authors have declared that no competing interests exist. * E-mail: okoraforka@yahoo.com

African gaint land snails are important as means of alleviating acute protein shortage in Nigeria livestock Industries. The present study aimed to study the influence of intensive and extensive management systems on the growth Performance of adult African Giant Land Snails (Archachatina marginata) was carried out in the wildlife domestication unit of the Department of Forest Resources and Wildlife Management, University of Benin, Benin City, Nigeria. Ninety African giant land snails (A. marginata) of average body weight 160.31g ± 0.38g were used for the study. The snails were grouped into two- Group A and Group B. 45 snails in group A were raised in an intensive system of management while 45 snails in group B were raised in an extensive system of management. The data collected on weight gain, shell length increment and shell width increment during the experiment were subjected to student t-Test at 5% significant level. Results showed that there was a significant difference at (p<0.05) in the weight gain. The intensive management system had a higher weight gain of 128.96g with mean value of 4.96 while the extensive management system had a weight gain of 88.37g with mean value of 3.40. There was no significant difference at (p>0.05) in the shell length increment. The snails in the extensive management system had the higher shell length increment of 5.32cm with mean value of 0.20 while the snails in the intensive management system had a shell length increment of 2.43cm with mean value of 0.09. There was a significant difference at (p<0.05) in the shell width increment. The snails in the extensive management system had the higher shell width increment of 9.31cm with mean value of 0.36 while the snails in the intensive management system had a shell width increment of 4.30cm with mean value of 0.17. The snails in the intensive system had a Feed Conversion Ratio of 5.03. For better growth performance of A. marginata in terms of weight gain, snail farmers should raise their snails in an intensive system of management and formulated diet should be used in feeding the snails along side with natural feed such as leaves and fruits.

The tropical invasive species Giant African Land Snail Lissachatina fulica is one of the worst of hundred invasive species in the world listed by IUCN. The snail severely affects agricultural and horticultural crops and home gardens throughout the tropics. The snail has reached India in 1847 and later it has spread into South India around the 1920s. An extensive survey was conducted in Tamil Nadu from 2016 to 2020 to detect the current distribution and assess the extent of damage caused to agriculture and horticulture crops by this snail. The Giant African Snail populations are found to be present in 29 localities spanning nine districts of Tamil Nadu. Fifteen snail samples were subjected to molecular characterization using the cytochrome oxidase subunit I (COI) gene. Three distinct haplotypes were identified by comparing the sequences with already available sequences from published research. The haplotype and nucleotide diversities were calculated and are found to be low when compared to other geographical regions. In urban inhabitations, the snail is found to be a menace in human settlements and the pest status of the snail is prominent in the rural areas of Tamil Nadu. The study has recorded that L. fulica now is an established pest in paddy, mulberry, banana, coconut, vegetable crops, tapioca, tuberose and several other important agriculture crops in several regions of Tamil Nadu.

Biodiversity loss is increasing globally due to many anthropogenic factors including invasive species. Among the invasive species, the giant African land snail which is World’s worst invasive species is threatening the native species and become major pest for economy loss. Although the impact of snail is widespread in Nepal, we have little knowledge on their distribution and spreading factors. Using species distribution modeling, we found more than 50% of their potential area at Tarai region followed by Siwalik (29%) and 20% in mid-hill regions. The findings indicated that the species has potential for spreading to the high-mountain areas due to road and transportation. Inspite of past history of the species occurrences, the current distribution expanded across the entire country in the low lands and mountain regions. Therefore, we recommend government to prevent the potential spreading of the giant African land snail in Nepal by developing and devising policy measures to control the species in and around the roadsides. In addition, we suggest the government for proper cleaning of vehicles and transporting materials before transportation or area specific quarantine through public awareness.

The use of dump soils for the rearing of African giant land snail (AGLS) leads to the bioaccumulation of metals and microbial loads in AGLS, which is a major food chain route for the human body. This study investigated the concentrations of heavy metals (As, Cd, Cr, Hg, and Pb) and microbial load in AGLS reared with dumpsite and control soil and also to ascertain if they are within permissible limits. Soil samples; dump soil (A), and Control soil (B) were collected at 0-30 cm depth with the aid of a soil auger and were used for AGLS farming, to ascertain whether the Toxic elements (TEs) concentration was within the permissible limits on AGLS consumption. A total of 18 juvenile snails of similar weights was used for the study. The experiment lasted for three months (90 days), during which the snails were subjected to similar dietary reign and equal quantity of feed. The soil samples were analyzed for TEs before and after farming, and a snail was also analyzed for TEs after farming using an atomic absorptions spectrophotometer (AAS). Standard methods of APHA were used to determine microbial loads such as Total heterotrophic bacteria, E. coli, total coliform, fecal coliform, Staphylococcus aureus, Salmonella, and intestinal parasites. Results indicated that bacterial counts recorded in this study exceeded the recommended levels by WHO and ICMSF, standards (i.e. 10 to 102 coliforms g-1, 10 fecal coliform g-1, and 4.9×106 aerobic count g-1). The result shows a significant difference (P<0.05) between the dump and the control soil The concentration of TEs (As, Cd, Cr, Hg, and Pb) in snails reared with dump soil were 2.20, 2.68, 1.08, 2.23, and 2.89 mg/kg respectively. The control recorded 0.28, 1.89, 0.36, 0.16 and 0.24 mg/kg. The values were greater than the maximum permissible limit of 0.5, 2.0, 0.3, 0.1, and 0.1 mg/kg respectively recommended by FAO/WHO compared to the control. The study concludes that snails bioaccumulate toxic elements and microbial loads from the soil used in rearing them which is deleterious to human health when consumed.

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.

The response of one hundred and thirty-two (132) grower African giant land snail (Archachatina marginata) with a weight range of 231.33-234.00 g and fed fresh pawpaw (Carica papaya) leaf-based diet supplemented with three mineral calcium sources was investigated in a humid tropical environment of Nigeria. The grower snails received either pawpaw leaves alone (T1: control), pawpaw leaf + egg shell (T2), pawpaw leaf + oyster shell (T3) or pawpaw leaf + periwinkle shell (T4). Each treatment groups was replicated 3 times in a Completely Randomized Design. The results showed that pawpaw leaf and calcium intakes differed (p < 0.05) ranging from the lowest for T1 to the highest for T3. Weight gain varied (p < 0.05) between 261.34 g for the T1 to 385.33 g for T2 while, feed conversion ratio ranged from 0.58 for T2 to 0.77 for T1. While shell length and width increments were not significantly different (p > 0.05), shell thickness was significantly different (p < 0.05) varying between 0.15 cm for T1 to 0.27 cm for T3. The study suggests that dietary calcium supplementation in the diets of the African giant land snail will improve the intake of a pawpaw leaf basal diet and mineral calcium, weight gain and feed conversion ratio with the oyster supplemented group performing better.

Epidemiology of Angiostrongylus cantonensis and eosinophilic meningitis in the People's Republic of China

This study determines localization of oestrogen hormone receptors in selected parts of the reproductive tract of giant African land snail (Archachatina marginata) and potential role of Mucuna pruriens on levels of expression. Thirty (30) snails were used for this experiment, with average weight of 100-150g. The snails were allotted to three dietary treatments which includes concentrate (CON), concentrate + Mucuna pruriens (CON+MSP) and Mucuna pruriens seed powder only (MSP). Each treatment contains 10 Replicate each. After eight weeks, five snails were randomly selected from each dietary treatment and dissected. Organs removed were oviduct, albumen gland, ovo-testis and the spermatheca. RNA and DNA extractions were carried out with commercial kits. Gel electrophoresis on 1% agarose was also carried out to evaluate the expression. Primers sequence used were the forward and reverse β oestrogen primer which was designed to detect the expression of the gene encoding oestrogen receptor in the reproductive tract of the giant African Land Snail (Archachatina marginata) were: Forward: 5’-GCT TCG AGC TCA GCC TG-3’ Reverse: 5’-AGG ATC ATG GCC TTG ACA CAG A-3’. Result showed that receptors for estrogen were present in oviduct, albumen gland, ovo-testis and spermatheca for both RNA and DNA analysis considering CON and MSP. While oviduct was also moderately expressed for CON and MSP. But combination of concentrate and Mucuna seed powder (CON+MSP) showed no visible expression for estrogen receptor. It was however concluded that combination of concentrate and mucuna seed powder (CON+MSP) down-regulate expression of estrogen receptor gene expression. It was recommended that feed to be combined for snail production must be free from substance(s) that has the potential to block the expression of reproductive hormone function.

Giant African land snails (Achatina fulica) are becoming increasingly popular pets and may be anaesthetised to allow diagnostics and surgical procedures. The objective of the present study was to evaluate the anaesthetic effects and anaesthetic-related complications of immersion in 5% ethanol in client-owned African pet land snails, anaesthetised to allow biopsies of the foot for screening of parasites. Variables such as minutes elapsing from immersion to anaesthetic induction and from removal from the bath to return of tentacle withdrawal reflex and recovery from anaesthesia were recorded, as well as the occurrence of adverse effects. Of the 30 snails enrolled, one (3.3%) had a fatal outcome whereas the remaining 29 (96.7%) snails completed the study and recovered from anaesthesia. Time to anaesthetic induction was 25 [25–29] minutes. Recovery was prolonged in one snail, which required 210 minutes to regain normal muscular strength. Time from removal from the ethanol solution to return of tentacle withdrawal reflex was 20 [14–42] minutes. Beside death, other observed adverse effects were production of bubbles (n = 4; 13.3%), and mucus secretion (n = 4; 13.3%). Immersion in 5% ethanol may be regarded as suitable anaesthetic technique for African giant snails for brief and moderately invasive surgical procedures. Nevertheless, recovery from anaesthesia may be prolonged and unpredictable.

Techniques for increasing the nutritional value of feeder invertebrates include dusting the prey items with a vitamin and mineral powder supplement, or providing the invertebrates with nutrient-rich food, called gut loading, prior to feeding to insectivores. However, the delay between gut loading of prey and consumption by insectivores varies according to feeding regime and may be considerable if prey is left in the vivarium. This study aimed to determine the effect of time post gut loading on the nutritional composition of three species of invertebrates, mealworms ( Tenebrio molitor larvae, approximately 23–30 mm), giant African land snails ( Achatina fulica , shell size 10–35 mm) and dubia cockroaches ( Blaptica dubia , approximately 20–30 mm). Feeder invertebrates were maintained on a dry commercial gut-loading diet, supplemented with fresh vegetables for 48 hours, after which the diet was removed. Samples of invertebrates (120 g of mealworms, 80 g of snails and 100 g of cockroaches) were taken for proximate analysis (dry matter, ash, crude fat and crude protein) at 0.5 h (excluding cockroaches), 1 h, 6 h and 12 h (excluding snails) using standard laboratory procedures. A one-way analysis of variance was performed to test for differences in nutrient content between time points in each species. Crude protein and fat contents of snails were significantly greater at 6 h compared to 0 h (P < 0.01). However, no other significant differences in nutrient content of snails or other species were detected at any time points. It is feasible that the increases in crude protein and fat of snails were a result of nutrient accumulation within the body. These findings indicate that in the species tested, with the exception of snails, delays of up to 12 hours between gut loading of the prey and their consumption by a carnivore are unlikely to affect the concentrations of macro-nutrients (protein, fat, dry matter and ash).

The giant African land snail, Lissachatina fulica (Bowdich 1822), has expanded its distribution throughout the tropics from its native region in Africa over the past 200 years and is a common species in urban environments. Multiple factors are associated with the presence and density of these species, and untangling the contribution of these factors is important in developing control strategies for this invasive species. The African Snail density was estimated in 1,056 sampling plots in Cali Colombia, and this variable was related to weather, microhabitat and habitat structure. This study indicated that the density of this species is mainly affected by climatic conditions, followed by habitat structural variables, and lastly by microclimatic characteristics. The strong El Niño Southern Oscillation (ENSO) during the period of this study significantly impacted the density of the snail through physiological and behavioral mechanisms, such as aestivation, physiological stress, and altered activity levels. The structure of the habitat also plays a crucial role, with higher densities observed in areas with high Normalized Difference Building Index (NDBI) values, likely due to the availability of calcium-rich substrates. The findings of this study highlight the detrimental effect of ENSO on the population density of the giant African land snail, but the resilience of the species suggests it will continue to thrive in specific urban habitats despite climatic challenges.

This study investigated the concentrations of heavy metals (As, Cd, Cr, Cu, Hg and Pb) in African Giant Land Snail (AGLS) treated with different soil samples dumpsite (A), mining site (B) and control soil (C) (a reserve area where no activities) use in farming AGLS and also to ascertain if they are within permissible limits and its ecological risk assessment on the consumption. Soil samples; at site A, B and C was collected at 0-30 cm depth with the aid of soil auger and were used for AGLS farming, to ascertain whether the potentially toxic elements (PTEs) concentration were within the permissible limits and their ecological risk assessment on AGLS consumption. A total of 54 juvenile snails of similar weights was used for the study. The experiment lasted for six month (182 days), during which the snails were subjected to similar dietary reign and equal quantity of feed. Snail’s morphological characteristics such as Weight, length and diameter of its shell were measured after farming. The soil samples were analysed for PTEs before and after farming, and snail were also analyzed for PTEs after farming for six month using atomic absorptions spectrophotometer (AAS). The ecological health risk from the consumption of these snails was assessed using standard methods and formulas. The result of different soil before and after farming shows a significant different (P&lt;0.05) between the activities sites (dump and mining) and the control site. The concentration of PTEs (As, Cd, Cr, Cu, Hg, and Pb) in snails treated with dump site soil were 3.05, 3.89, 3.60, 2.89, 3.98, and 2.55 mg/kg, and snails treated with mining site soil recorded 2.73, 2.74, 3.91, 4.96, 2.88 and 4.82 mg/kg. The values were greater than the maximum permissible limit of 0.5, 2.0, 0.3, 0.04, 0.1 and 0.1 mg/kg respectively recommended by FAO/WHO compared to the control. The study concludes that snail bioaccumulate toxic elements from the soil used in rearing them which is deleterious to humans when consumed. Also the DIM, HQ, HI on the consumption of snail reared with dumpsite, mining site soils are nearly free of risks, but continuous consumption can lead to bioaccumulation in the food chain.

High lability of global niche and range in the Giant African Snail (Lissachatina fulica): Small niche expansions resulting in large range shifts