Search

Abstract Snail secretion is a complex mixture of several components, including proteins, glycoproteins, mucopolysaccharides and smaller molecules. Its growing use in nutraceutical, cosmetic and biomedical applications, as well as a component of edible and green packaging to replace chemical plasticizer, implies more affordable and sustainable extraction methods. We chose four extracts obtained from Cornu aspersum snails, different by origin, extraction medium (namely, citric acid, lactic acid or none) and additives and we performed a series of characterizations including the SDS-page, the measure of pH and density, the evaluation of dry matter and of protein content, supported by structural determinations by means of UV-visible and infrared spectroscopy, X-Rays diffraction and thermogravimetric measurements. Biological assays comprising evaluation of cytotoxicity and antibacterial activity were also carried out. All the tests were performed both on the as received snail filtrates and on the samples after proper dialysis to remove preservatives added by manufacturers. The obtained results put into evidence that the properties and composition of the final extract are strongly influenced by the collection method, that can be relevant for the proper use of snail filtrate in specific applications.

Simple Summary: Nutrition is one of the most important physiological processes for the growth and welfare of farmed animals, while interactions between the intestinal microflora and the host systems provide a key mechanism for enhancing and maintaining homeostasis. Probiotics exert a positive impact on organisms' growth and immune response, so the administration of rations enriched with probiotics is recommended. Although the physiological role of probiotics on vertebrates' growth and stress responses has been extensively studied in vertebrates, little is known regarding their effects on economically important invertebrates such as land snails. The aim of the present study was to investigate the effects of probiotic-enriched rations on the physiological responses in several tissues of the economically important farmed terrestrial snail, Cornu aspersum. Despite the absence of a direct effect on growth rate, an intense physiological response by various biomarkers was observed in all examined tissues. A large variety of microorganisms ingested with food constitute animals' intestinal microflora, enhancing and maintaining the homeostasis of the host. Rations enriched with probiotics are a method recommended to prevent undesirable conditions. To date, research has been limited to farmed animals and reared fish, creating a knowledge gap concerning the effect of probiotics on the growth rate, physiological responses, and energy metabolism of invertebrates such as the land snail Cornu aspersum. Herein, juvenile snails (26.23 ± 0.5 mm shell diameter and 8.23 ± 1.02 g body weight) were fed L. plantarum probiotic-enriched rations in two different proportions (1.25 mg and 2.5 mg), and their growth rate was monitored for three months. Additionally, the RNA/DNA and Bax/Bcl-2 ratios, HSP gene expression and protein levels, and ND2 expression, were measured in the hepatopancreas, digestive tract, and mantle. Although the snails' growth rate was not affected, the RNA/DNA ratio presented an increase in various tissues, indicating an intense physiological response. Also, probiotic administration demonstrated low levels of the Bax/Bcl-2 ratio. HSP levels were higher in the presence of probiotics, probably signaling an attempt by the animal to face potentially stressful situations. Finally, ND2 expression levels in the hepatopancreas indicate intense metabolic and antioxidant activity. [ABSTRACT FROM AUTHOR]

The aim of this study was to assess the changes occurring as a result of boiling (100°C, 1 h) small brown snail (Cornu aspersum aspersum) meat in relation to its proximate composition, calcium, phosphorus and cholesterol content, as well as the profile of fatty acids and nutritional quality indices of the lipids. This species of snail was selected for research because it is currently of the greatest economic importance among edible terrestrial snails. It was hypothesized that the cooking effect may be different for foot and visceral sac. Samples for the research were collected from 6 populations bred on experimental fields of the National Research Institute of Animal Production in balice (Poland). The foot and the visceral sac, the edible parts of the snail species under investigation, were analysed separately, raw and boiled in water. The results were then compared to analogous studies carried out by other authors on beef, pork and poultry. It was found that in the visceral sac of Cornu aspersum aspersum the shares of dry matter, crude protein, fat, ash, calcium and phosphorus were greater than those in the foot (P<0.05), both in the raw and boiled material, whereas the cholesterol content was higher in the foot (P<0.05). Generally, especially in the foot, the heat treatment elevated the levels of the afore-mentioned quantities, yet the increases were not always statistically significant. Boiling the snail meat caused moderate changes in the fatty acid composition. The profile of the fatty acids and the nutritional quality indices of the foot fat were more advantageous than those in the visceral sac. In both parts of the snail carcass, the polyunsaturated fatty acids/saturated fatty acids (PUFA/SFA) ratio substantially exceeded the minimum value of 0.45 recommended by the British Department of Health. However, the n-6/n-3 ratio was too high, exceeding the maximum recommended level of 4.0 twofold and as much as threefold in the case of the foot and the visceral sac, respectively. In the foot, due to boiling, an increase of the share of sfa and monounsaturated fatty acids (MUFA) was observed, while PUFA, n-6 and n-3 decreased. In the visceral sac, the changes were less pronounced with a slight decrease of the share of sfa and PUFA, and an increase of MUFA. Therefore, in the foot, boiling worsened the PUFA/SFA ratio, the nutritive value index (NVI = (C18:0 + C18:1) / C16:0) and dietary fatty acids having a desirable neutral and hypocholesterolemic effect in humans (DFA = Σ MUFA + Σ PUFA + C18:0), but in the visceral sac these indices practically did not change. On the whole, the trends of the changes in terms of chemical composition due to boiling found in the small brown snail meat are similar to those after heat treatment of meat from popular farm animals, but the ranges of the changes differ. [ABSTRACT FROM AUTHOR]

Edible snails are an attractive protein source due to their high growth rate, cost-efficiency, and nutritional value. Calcium is crucial for snail growth, reproduction, and shell formation, while magnesium plays a role in enzyme function and muscle tone. This study aimed to optimise calcium and magnesium levels in Cornu aspersum diets to optimise the production and technological characteristics of the derived animal products. Snails were fed specific diets in controlled conditions with varying calcium and magnesium levels (44.3, 66.1, 88.7, 103.5 Ca g/kg feed and 3.3, 5.6, 7.2 Mg g/kg feed) for four months. Their growth, shell characteristics, and meat composition were evaluated. As calcium in the feed increased, carcass and shell weights were higher. Also, the crushing force of the shells was higher with increasing amount of calcium in the feed. In the group with 10.35% calcium and 0.72% magnesium, snail growth significantly slowed down after three months, with lower mortality. It is suggested that a shortened fattening cycle by 3–4 weeks compared to the magnesium-free diet is possible. However, based on meat, shell, mortality, and feed intake analysis, a 0.56% magnesium concentration in the feed seems to give better results, as magnesium content at 0.72% might be toxic to snails. Further investigation is to confirm the possibility of neutralising the negative effects of magnesium in the diet through increasing calcium and phosphorus intake. [ABSTRACT FROM AUTHOR]

In this study we describe the functional morphology of Cornu aspersum (Helix aspersa), spermatozoa using light, scanning (SEM) and transmission electron (TEM) microscopies. The studies were performed with sperm located in the frozen hermaphroditic duct. Our results showed that the head presents an elongated conical shape slightly coiled in a corkscrew, with the nucleus partially covered by an acrosome, where an apical vesicle is located at the lateralized apex. This peculiar shape suggests the helical displacement movement of the spermatozoa. The head and the nucleus are slightly larger size compared to those of other gastropod species. The intermediate tract is surrounded by a mitochondrial complex and a glycogen helix. The glycogen helix is coiled helically along the intermediate tract, presenting at least five twists of glycogen helices. The complexity of both the mitochondrial complex and the glycogen helix suggests a high metabolic consumption considering the long period of time until fertilization occurs. Our findings on the detailed characterization of Cornu aspersum spermatozoa, obtained from a frozen hermaphroditic duct can contribute to a better understanding of the functional morphology of sperm and serve as a reference for future studies. [ABSTRACT FROM AUTHOR]

Abstract Plant–herbivore interactions mediated by plant–plant signalling have been documented in different species but its within‐species variability has hardly been quantified. Here, we tested if herbivore foraging activity on plants was influenced by a prior contact with a damaged plant and if the effect of such plant–plant signalling was variable across 113 natural genotypes of Arabidopsis thaliana. We filmed the activity of the generalist herbivore Cornu aspersum during 1 h on two plants differing only in a prior contact with a damaged plant or not. We recorded each snails' first choice, and measured its first duration on a plant, the proportion of time spent on both plants and leaf consumption. Overall, plant–plant signalling modified the foraging activity of herbivores in A. thaliana. On average, snails spent more time and consumed more of plants that experienced a prior contact with a damaged plant. However, the effects of plant–plant signalling on snail behaviour was variable: depending on genotype identity, plant–plant signalling made undamaged plants more repellant or attractive to snails. Genome‐wide associations revealed that genes related to stress coping ability and jasmonate pathway were associated to this variation. Together, our findings highlight the adaptive significance of plant–plant signalling for plant–herbivore interactions.

A large variety of microorganisms ingested with food constitute animals’ intestinal microflora, enhancing and maintaining the homeostasis of the host. Rations enriched with probiotics are a method recommended to prevent undesirable conditions. To date, research has been limited to farmed animals and reared fish, creating a knowledge gap concerning the effect of probiotics on the growth rate, physiological responses, and energy metabolism of invertebrates such as the land snail Cornu aspersum. Herein, juvenile snails (26.23 ± 0.5 mm shell diameter and 8.23 ± 1.02 g body weight) were fed L. plantarum probiotic-enriched rations in two different proportions (1.25 mg and 2.5 mg), and their growth rate was monitored for three months. Additionally, the RNA/DNA and Bax/Bcl-2 ratios, HSP gene expression and protein levels, and ND2 expression, were measured in the hepatopancreas, digestive tract, and mantle. Although the snails’ growth rate was not affected, the RNA/DNA ratio presented an increase in various tissues, indicating an intense physiological response. Also, probiotic administration demonstrated low levels of the Bax/Bcl-2 ratio. HSP levels were higher in the presence of probiotics, probably signaling an attempt by the animal to face potentially stressful situations. Finally, ND2 expression levels in the hepatopancreas indicate intense metabolic and antioxidant activity.

Plant–herbivore interactions mediated by plant–plant signalling have been documented in different species but its within‐species variability has hardly been quantified. Here, we tested if herbivore foraging activity on plants was influenced by a prior contact with a damaged plant and if the effect of such plant–plant signalling was variable across 113 natural genotypes of Arabidopsis thaliana. We filmed the activity of the generalist herbivore Cornu aspersum during 1 h on two plants differing only in a prior contact with a damaged plant or not. We recorded each snails' first choice, and measured its first duration on a plant, the proportion of time spent on both plants and leaf consumption. Overall, plant–plant signalling modified the foraging activity of herbivores in A. thaliana. On average, snails spent more time and consumed more of plants that experienced a prior contact with a damaged plant. However, the effects of plant–plant signalling on snail behaviour was variable: depending on genotype identity, plant–plant signalling made undamaged plants more repellant or attractive to snails. Genome‐wide associations revealed that genes related to stress coping ability and jasmonate pathway were associated to this variation. Together, our findings highlight the adaptive significance of plant–plant signalling for plant–herbivore interactions. [ABSTRACT FROM AUTHOR]

Dietary ingestion is the main route of exposure to hazardous contaminants in land animals. Cadmium, a high-profile toxic metal, affects living systems at different organismal levels, including major storage organs (liver, kidneys), key organs for species survival (gonads), and epigenetic networks regulating gene expression. 5-methylcytosine (5mC) is the most common and best-characterized epigenetic mark among different modified nucleosides in DNA. This important player in methylation-driven gene expression is impacted by cadmium in sentinel terrestrial vertebrates. However, limited information exists regarding its impact on macroinvertebrates, especially land snails commonly used as (eco)toxicological models. We first investigate the methylomic effects of dietary cadmium given as cadmium nitrate on terrestrial mollusks. Mature specimens of the common brown garden snail, Cornu aspersum, were continuously exposed for four weeks to environmentally-relevant cadmium levels. We determined global genomic DNAmethylation in hepatopancreas and ovotestis, as well as changes in the methylation status of CG pairs at the 50 region close to the transcription site of gene encoding the Cd-selective metallothionein (Cd-MT). Weight gain/loss, hypometabolism tendency, and survival rates were also assessed. Although this exposure event did not adversely affect survival, gastropods exposed to the highest Cd dose revealed a significant reduction in body weight and a significant increase in hypometabolic behavior. The hepatopancreas, but not the ovotestis, displayed significant hypermethylation, but only for the aforementioned specimens. We also found that the 50 end of the Cd-MT gene was unmethylated in both organs and its methylation status was insensitive to cadmium exposure. Our results are important since they provide scientists, for the first time, with quantitative data on DNA methylation in gastropod ovotestis and refine our understanding of Cd epigenetic effects on terrestrial mollusks. [ABSTRACT FROM AUTHOR]

Summary: A new nematode species, Phasmarhabditis villasmundi sp. n., was isolated from land gastropods in the Villasmundo-S. Alfio Nature Reserve in Syracuse Province, Sicily. Phasmarhabditis villasmundi sp. n. is characterised by the presence of males and females in the population and is recognised mainly by a conical female tail with prominent phasmids at its mid-length, spicules ca 82 μ m long with a hole at the distal tip, infective juveniles with an average length of 773 μ m and the distinct molecular characteristics of the new species. It is the second member of the genus described from Italy apart from P. apuliae Nermut' et al., 2016 and is morphologically closest to this species. However, phylogenetic analyses based on ITS and D2-D3 LSU placed P. villasmundi sp. n. close to European P. neopapillosa and P. hermaphrodita , while P. apuliae appeared to be related to P. bohemica and the New World's P. californica. [ABSTRACT FROM AUTHOR]

In the past three decades, a significant progress has been made in the prevention and treatment of gastric ulcers. The incidence of the disease has decreased, but gastric ulcer is still a medical problem. Currently, the available drugs for gastric ulcer treatment have many side effects; therefore, searching for new and safe therapeutic agents is mandatory. The present study aims to investigate the gastroprotective potential of Cornu aspersum (C. aspersum) mucin against gastric ulcers, and the mechanisms related to oxidative stress and inflammation. C. aspersum mucin was collected from 50 snails. The characteristics of C. aspersum mucin (chemical and microbiological) were evaluated. Mice were pretreated with famotidine and C. aspersum mucin (7.5 and 15 ml/kg b.w.) for 5 days, and then gastric ulcers were induced by indomethacin. Macroscopic examination, biochemical estimations, and Quantitative real-time PCR were carried out. Also, histopathological and immunohistopathological examinations were evaluated. We found that the high dose of the mucin significantly decreased the gastric mucosal malondialdehyde (MDA) and nitric oxide (NO) contents as well as interleukin 1β (IL-1β) and nuclear factor kappa β (NF-ҡB) expression, and inducible nitric oxide synthase (iNOS) immunostaining. It also increased the gastric mucosal GSH and catalase contents as well as hemoxygenase-1 (HO-1) and nuclear factor-erythroid 2-related factor 2 (Nrf2) expressions with regressions in gastric mucosal lesions. In conclusion, C. aspersum mucin could be a potential therapeutic candidate to protect against gastric ulceration.

The objective of this study was to estimate genetic parameters for body weight at 60 (P60), 90 (P90), and 120 (P120) days of age in escargots of the subspecies Cornu aspersum maximum, evaluating the influence of fixed and covariable effects on these traits. The data used were collected from escargots kept in a total confinement system. The significant fixed effects and covariates for these traits were tested in a general linear model by the F-test, considering a level of significance of 5%. Both the fixed effects of box and birth year and the quadratic effect of age of weighing as a covariate were significant (p < 0.05) for P60, P90, and P120. The Restricted Maximum Likelihood (REML) methodology was used to estimate (co)variance components and genetic parameters. High heritability for P60, P90, and P120 (0.38, 0.55 and 0.78, respectively) and high genetic correlations (0.58 to 0.77) among the traits were observed. The genetic parameters can be used as a basis for studies and practical applications to increase zootechnical indexes in this population. [ABSTRACT FROM AUTHOR]

Terrestrial edible snail breeding is an agricultural activity that finds itself at pioneering stage in Romania. One of the species used in snail farming is Helix aspersa Muller. In order to accelerate their growth, farmers feed the snails with pumpkins as well as concentrated forage consisting of mix of flours to which calcium carbonate is added in order to supplement snails need for shell’s development. In a controlled microclimate environment we measured the average growth of six weeks old Helix aspersa Muller snails placed in four different plastic enclosures. The consumption of different type of foods within 24 hours period was measured. The wheat (60%), corn flour (20%) and calcium carbonate (20%) mix had a superior food conversion ratio (FCR) of 4.80, whereas the second FCR registered 6.04 in the case of 53% pumpkin and 47% flour mix served in the same time followed by the pure fresh vegetable mix accounting for a FCR of 8.00 and by 19.02 when only the pumpkin has been administrated as meal. During the experiments the snails did not have access to soil, being known that soil is an integral part of their diet.

We used Helix pomatia and Helix aspersa species and measure their growth as the snails were approaching the hibernation season. Helix pomatia 2yo shown a decrease in weight while being raised in enclosed parcels of 4sqm the younger Helix pomatia 1yo as well as Helix aspersa Muller demonstrated the ability to adapt relatively fast to the same conditions. We established 5 experimental lots in a Helix pomatia farm, GPS coordinates N46.606040 E23.599950. Control lot contained Taraxacum officinales, Sonchus oleraceus, Equisetum arvense and Atriplex hortensis, wild flora found within the farm. The other lots contained the same plants as the control lot plus different combinations of imported plants from other areals. The H. pomatia 2yo weight decreased in the control lot by a mean of -3.86% while H. aspersa 1yo marked an increase of +16.89% in the same lot during the same period. The lot containing lupinus polyphyllus delivered snails with weight gain of +24.66% for H. pomatia 2yo and an increase of only +1.98% for H. aspersa 1yo. As a contrast, H. pomatia 2yo gained only +7.72% while H. aspersa 1yo gained +28.89%, in the lot containing Lavanda officinalis, Foeniculum vulgare and Hyssopus officinalis among the other plants.

Edible snails are an attractive protein source due to their high growth rate, cost-efficiency, and nutritional value. Calcium is crucial for snail growth, reproduction, and shell formation, while magnesium plays a role in enzyme function and muscle tone. This study aimed to optimise calcium and magnesium levels in Cornu aspersum diets to optimise the production and technological characteristics of the derived animal products. Snails were fed specific diets in controlled conditions with varying calcium and magnesium levels (44.3, 66.1, 88.7, 103.5 Ca g/kg feed and 3.3, 5.6, 7.2 Mg g/kg feed) for four months. Their growth, shell characteristics, and meat composition were evaluated. As calcium in the feed increased, carcass and shell weights were higher. Also, the crushing force of the shells was higher with increasing amount of calcium in the feed. In the group with 10.35% calcium and 0.72% magnesium, snail growth significantly slowed down after three months, with lower mortality. It is suggested that a shortened fattening cycle by 3–4 weeks compared to the magnesium-free diet is possible. However, based on meat, shell, mortality, and feed intake analysis, a 0.56% magnesium concentration in the feed seems to give better results, as magnesium content at 0.72% might be toxic to snails. Further investigation is to confirm the possibility of neutralising the negative effects of magnesium in the diet through increasing calcium and phosphorus intake.

This study investigated the eggs of Polish-bred edible snails of the Cornu genus as a food and aimed to determine the presence of microorganisms in them of the Salmonella and Listeria genera and ascertain the number of coagulase-positive staphylococci.

The objective of this study was to estimate genetic parameters for body weight at 60 (P60), 90 (P90), and 120 (P120) days of age in escargots of the subspecies Cornu aspersum maximum, evaluating the influence of fixed and covariable effects on these traits. The data used were collected from escargots kept in a total confinement system. The significant fixed effects and covariates for these traits were tested in a general linear model by the F-test, considering a level of significance of 5%. Both the fixed effects of box and birth year and the quadratic effect of age of weighing as a covariate were significant (p < 0.05) for P60, P90, and P120. The Restricted Maximum Likelihood (REML) methodology was used to estimate (co)variance components and genetic parameters. High heritability for P60, P90, and P120 (0.38, 0.55 and 0.78, respectively) and high genetic correlations (0.58 to 0.77) among the traits were observed. The genetic parameters can be used as a basis for studies and practical applications to increase zootechnical indexes in this population.

Snail eggs can be the raw material for the production of a caviar substitute. The substitute varies from the original in caloric value and nutrient content which determine the nutritional value of every foodstuff. The present study aimed to determine and compare the nutritional value and protein quality of eggs from two subspecies of edible snail.

Abstract The search for new natural compounds for application in medicine and cosmetics is a trend in biotechnology. One of the sources of such active compounds is the snail mucus. Snail physiology and the biological activity of their fluids (especially the mucus) are still poorly studied. Only a few previous studies explored the relationship between snails and their microbiome. The present study was focused on the biodiversity of the snail mucus used in the creation of cosmetic products, therapeutics, and nutraceuticals. The commonly used cultivation techniques were applied for the determination of the number of major bacterial groups. Fluorescence in situ hybridization for key taxa was performed. The obtained images were subjected to digital image analysis. Sequencing of the 16S rRNA gene was also done. The results showed that the mucus harbors a rich bacterial community (10.78 × 1010 CFU/ml). Among the dominant bacteria, some are known for their ability to metabolize complex polysaccharides or are usually found in soil and plants (Rhizobiaceae, Shewanella, Pedobacter, Acinetobacter, Alcaligenes). The obtained data demonstrated that the snail mucus creates a unique environment for the development of the microbial community that differs from other parts of the animal and which resulted from the combined contribution of the microbiomes derived from the soil, plants, and the snails.

The aim of this study was to determine the content of fatty acids in eggs harvested from two edible subspecies of Polish-bred common garden snail from the Cornu genus, as well as this content in the retail-ready product obtained from these eggs.

Helix grisea was described by Linnaeus in 1758, and its identity has been doubtful ever since. The name features in the early taxonomic history of some other species of Helix sensu lato. Here I provide a summary of the history of its use. Mostly, the name was applied for the widespread species now accepted as Cornu aspersum (O. F. Müller, 1774), while a few authors used it for Helix cincta O. F. Müller, 1774. Neither usage is in line with the Linnaeus' account. Based on a figure to which Linnaeus referred, I propose that the name originally applied to a species now known as Helix lucorum Linnaeus, 1758 and as the first reviser, I give precedence to H. lucorum over H. grisea. In respect to C. aspersum, H. grisea cannot take precedence because of reversal of precedence according to Art. 23.9, and is pronounced a nomen oblitum. The case of H. grisea illustrates the importance of Müller's work for the taxonomy of the genus. In this respect it is regrettable that some of his species, including C. aspersum, lack a known and well documented type specimens.

In vivo biomimetic biomineralization using living organisms known as biomineralizers is currently a major research trend. Industrially cultivated terrestrial snails, such as the common garden snail Cornu aspersum, represent a simple model organism that is ideal for use in experiments on the regeneration of the calcified shell after the excavation of a corresponding shell fragment. The mollusk's artificially damaged shell is regenerated via the formation of an organic regenerative membrane, which serves as a native template for in vivo biocalcification. In this study, for the first time, a special plexiglass device for non-lethal fixation of living snails, enabling real-time monitoring of their ability to regenerate their shells using digital microscopy, has been proposed and tested. As an alternative to natural biomineralization using the mollusk's own sources, we propose chitin- and collagen-based templates, which have been shown to be effectively calcified by living snails. The results indicate that the type of organic template used for in vivo biomineralization has a substantial effect on the nature of the mineral phases. [ABSTRACT FROM AUTHOR]

The proximate and amino acid compositions of the visceral mass and pedal mass of wild and farmed land snail Cornu aspersum were compared. The lipid in all body parts of farmed snail was significantly higher than all body parts of wild snail. The ash content of wild snail pedal mass was higher than all body parts of farmed snails. The dominant amino acid was glutamic acid (Glu), while the highest values of essential amino acids were leucine (Leu) and arginine (Arg) in all body parts of all snails. Sulfur amino acid was the lowest value in C. aspersum, which indicated that methionine (Met) and cysteine (Cys) could have been the first limiting amino acids. The study results showed that the protein efficiency rate (PER) of C. aspersum is close to PER of egg, which indicates a high protein quality and high biological value of land snails. The study also demonstrated that the experimental diet had good acceptability and well-balanced essential amino acid content, meaning that the farmed snails could have almost the same protein characterization as wild snails. Thus, all body parts of both wild and farmed C. aspersum have high protein quality. [ABSTRACT FROM AUTHOR]

Copyright of Parasite (1252607X) is the property of EDP Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We utilized a social media website (Facebook) to gather information from citizen scientists on their observations of the introduced large land snail species Cornu aspersum, and Helix lucorum in Budapest, Hungary. In a Facebook post we presented the project to reveal where the two species occur in Budapest, together with an identification guide which included images. In this study we compiled information received in the two months following the Facebook post. We obtained 44, 92 and 105 locality observations of H. lucorum, the native H. pomatia and C. aspersum, respectively in the city, mostly within five days after the post. Our Realtime Social Networking Service (RSNS) method, which included intensive communication with citizen scientists, revealed that C. aspersum was spread in most areas across Budapest, except for the Buda region west of the Danube where H. lucorum dominates. Their distributions overlapped with each other only in small ranges. We found that no specimens of these non-indigenous species were present in the collection of L. Drimmer, who extensively collected land snails in the city in the early 1990s. Accordingly, the two non-indigenous species most probably established their current distributions in Budapest in the last 30 years. Our study demonstrates that RSNS method efficiently and rapidly reveals distributions of relatively large animal species in city areas and provides a dependable basis for further research. [ABSTRACT FROM AUTHOR]

The metastrongyloid Aelurostrongylus abstrusus has an indirect lifecycle involving gastropod intermediate hosts. The widespread snail Cornu aspersum is an efficient intermediate host of A. abstrusus. As the temperature may influence the developmental rate of metastrongyloids from first (L1) to the third infective larval stage (L3) inside molluscs, this study evaluated the effect of two controlled temperatures on the development of A. abstrusus in C. aspersum. Overall, 300 snails were infected with 500 L1 of A. abstrusus and kept at ∼25 °C. Fifteen days post infection (D15), the overall developmental rate to L3 (0.8%) was assessed in a subset of 20 snails. The remaining gastropods were divided in 2 groups, i.e., 180 still kept at ∼25 °C (G1) and 100 hibernated at ∼4 °C (G2). On D30, the larval development was evaluated in 20 snails from each group, while another batch of 80 snails was selected random from G1 and hibernated at ∼4 °C (G3). The larval developmental rate was determined digesting 20 snails from each of the three groups on D45, D60, and D75. The higher mean developmental rate was registered in G1 (3.8%) compared to G2 (1.9%) and G3 (2.3%), indicating that the development to L3 of A. abstrusus in C. aspersum is positively influenced by the increase of temperature.

(1) Background: Hibernation in pens covered with LFC was associated with high mortality of C. aspersum snails in Romanian snail farms. This three-year study aimed to develop a simple, but effective system for protecting breeders in colder climates. (2) Methods: The first phase investigated the (pre)hibernal burrowing behavior and the overwintering habitat choice. Protective structures based on straw, LFC, and/or HDPE were tested at pilot level (no snails). The most suitable system was applied under farm conditions. (3) Results: Wood and ridge-tile micro shelters were significantly preferred to corrugated iron micro shelters. Burrowing specimens acted as shallow-burrowers, and this behaviorwas significantly more common for looser soils. All pilot systems displayed significantly higher thermal protection efficiency compared to the sole use of LFC. The balance between straw moistening and thermal protection favored using structure soil/LFC/straw/10-cm air cushion/HDPE. Its use yielded significantly higher survival compared to the sole use of LFC. Most hibernating snails clustered together in large groups, attached on the lower surface of micro shelters. Predator occurrence appeared to marginally affect overwintering survival. (4) Conclusions: The “sandwich” system could be an effective solution for overwintering mature C. aspersum snails in colder climates.

Introduction: The objective of the present research was to carry out a comparative assessment of copper, zinc, and selenium concentrations in the meat of edible land snails collected in Poland (Helix pomatia, Cornu aspersum maxima, and Cornu aspersum aspersum), as well as to determine the effect of preliminary processing of Roman snails (Helix pomatia) on the content of the aforementioned elements. Material and Methods: In the first stage, determinations were made on unprocessed snail meat. In the second stage, the study focused on Roman snails and consisted in an additional evaluation of frozen meat after full processing. Zinc and copper contents were determined by flame atomic absorption spectrometry and the selenium content was established by graphite furnace atomic absorption spectrometry. Results: The selenium content differed significantly among all three species. The copper content in Roman snails differed significantly from that in farmed snails. No significant difference in the zinc level was noted among the three snail species. The selenium content in raw and processed meat of Roman snails did not show any significant difference while the copper and zinc level was significantly higher in processed meat samples. Conclusion: The present research on the meat of edible snails showed different levels of selenium, copper, and zinc, depending on the species, collection site, and subjection to processing.

Urban areas with residential yards (= domestic gardens) provide a diverse environmental mosaic characterized by high plant architectural and species diversity and variation in yard management practices among residents. For small, slow-moving taxa such as land snails, this mosaic provides an unplanned experiment to document dispersal patterns and conditions influencing this pattern. The snail Cornu aspersum is a Mediterranean-native that was likely introduced into a Norman, Oklahoma (USA) yard through the plant trade. Cornu spread across 16 residential yards (and up to 110 m) in a single block over a period of at least 6 years, moving in a diffusive dispersal pattern. Supplemental water (e.g., watered plant beds and ponds) combined with nearby shelters contributed to increased local density but may also result in targeted snail control. Although roads contributed to the species arrival, roads were barriers to short-term snail self-dispersal and the limited road crossing may have been human-mediated (e.g., snails carried on potted plants). Dispersal was limited across non-residential properties with expansive grass lawns and parking lots. Residential areas provide a good model system for examining factors associated with the spread of non-native species, especially for species having low mobility. [ABSTRACT FROM AUTHOR]

Abstract Accurate dating of young (<10 ka) volcanic rocks poses numerous challenges yet determining eruption ages is critical to understanding magmatic evolution and hazards associated with active volcanic centers. 14C dating is the preferred technique for dating young geologic materials, but a few studies have suggested that volcanic degassing can result in erroneously old 14C dates (e.g. Pasquier-Cardin et al., 1999). Finding an isotopic system with which to accurately constrain eruptive recurrence intervals at recently active volcanic centers is critical to assessing future volcanic hazards. In this study, we have obtained 14C data from modern terrestrial gastropods on São Miguel island, Azores to assess the current impact of volcanic degassing on 14C ages near active and extinct volcanic centers, and for one active volcanic center, we have compared 14C of paleosols with 226Ra-230Th maximum eruptive ages for pumices immediately overlying the respective paleosols. 14C ages of the modern terrestrial gastropod Cornu aspersum demonstrate the effects of dilution from a range of current outgassing levels at three active trachytic stratovolcanoes on São Miguel island: Sete Cidades, Fogo, Furnas, as well as the extinct Povoação volcano. A modern gastropod sampled at Furnas, where there is evidence of extensive present-day degassing, has a 14C age of 394 ± 97 cal BP. At Fogo volcano, also a location with active degassing, the 14C age of a modern gastropod is 1324 ± 60 cal BP. Both of these ages clearly show effects of dilution of atmospheric 14C due to volcanic degassing. In contrast, there is currently no apparent outgassing occurring at Sete Cidades or Povoação, and modern gastropod ages from these volcanoes are post-bomb. We also obtained 14C data from paleosols and 226Ra-230Th ages associated pumices from the youngest eruptive sequence of Sete Cidades volcano, the Pepom P1–P17 deposits, the ages of which are poorly constrained but thought to be <5000 years (Queiroz, 1997). 226Ra-230Th disequilibrium in a P1 glass separate indicates a maximum eruptive age of 4440 ± 195 years. 14C ages of paleosols below P1 and P3 are older than those derived from 226Ra-230Th dating, at 7293 ± 141 cal BP and 7698 ± 172 cal BP, respectively. We interpret the 14C ages as being erroneously old due to abundant volcanic degassing at the time of eruption. Similarly, but to a lesser extent, the 226Ra-230Th maximum eruptive age of glass separated from the P8 eruption is 2659 ± 55 y, whereas the age of the paleosol sampled directly beneath P8 is older (3054 ± 194 y BP). In contrast, paleosols sampled at multiple field localities from below the most recent eruptive deposit (P17) are within error of each other (476 ± 56 cal y BP and 585 ± 68 cal y BP), while 226Ra-230Th maximum eruptive ages in glass separates from two different P17 sampling sites are 762 ± 14 y and 730 y ± 15 y. This is consistent with the observation that Sete Cidades volcano is experiencing limited hydrothermal activity at the present time and likely had similarly low levels of degassing just prior to the last eruption. The average eruptive recurrence interval for the P1–P17 deposits, based on 226Ra-230Th maximum eruptive ages from P1 and P8 and 14C ages from P17, is ~230 years. This recurrence interval is similar to the ~200 y eruptive recurrence interval at Furnas volcano and much shorter than the ~1200 y eruptive interval at Fogo volcano. This has important implications with respect to volcanic hazards and should be considered in any future volcanic hazard planning. Highlights • Modern day gastropods show effects on 14C ages from volcanic degassing. • 14C ages of P1–P17 paleosols show effects on 14C ages from volcanic degassing. • Paired Ra-Th and 14C dates help constrain recent Sete Cidades eruptive history. [ABSTRACT FROM AUTHOR]

Background and Aims Seedling herbivory is an important selective filter in many plant communities. The removal of preferred food plants by both vertebrate and, more commonly, invertebrate herbivores can destroy entire seedling cohorts, and consequently dictate plant community assembly. Nevertheless, our understanding of how and why some seedlings are more prone to herbivore attack than their neighbours remains limited. For seedlings, where even minor tissue damage is fatal, avoiding contact with herbivores is probably advantageous and, on this basis, volatile organic compounds (VOCs) are strong candidates to fulfil a primary defensive role. Methods We quantified seedling selection by snails (Cornu aspersum) for 14 common, European grassland species. Seedling acceptability was subsequently compared with species-specific expression of constitutive secondary defence metabolites (CSDMs), and VOCs to determine their relative influence on seedling selection. Results We found no relationship between seedling acceptability and CSDMs, but seedling selection was strongly associated with VOC profiles. Monoterpenes (specifically β-ocimene) were identified as likely attractants, while green leaf volatiles (GLVs) (3-hexen-1-ol acetate) were strongly associated with low seedling acceptability. Conclusions By elucidating a relationship between VOCs and seedling acceptability, we contradict a long-held, but poorly tested, assumption that seedling selection by herbivores in (semi-)natural plant communities centres on CSDMs. Instead, our results corroborate recent work showing how GLVs, including 3-hexen-1-ol acetate, deter crop seedling selection by molluscs. Although our failure to establish any early-ontogenetic relationship between VOCs and CSDMs also suggests that the former do not 'advertise' possession of the latter, we nevertheless reveal the role that VOCs play in defending seedlings against herbivory before lethal damage occurs. [ABSTRACT FROM AUTHOR]

The dynamics of the bacterial community in the intestinal tract of Cornu aspersum was investigated during different states of its life cycle. Two approaches were applied – culture and non-culture. The non-culture approach was performed by ARDRA of 16S rDNA using two of the six tested endonucleases. Data were analyzed by hierarchical cluster analysis. The restriction of 16S rDNA samples from the snail of different physiological states with endonucleases HinfI and Csp6I resulted in generation of different profiles depending on the snail states. By the culture approach we found that the total number of cultivable bacteria, representatives of Enterobacteriaceae, lactic acid bacteria, amylolitic and cellulolytic bacteria were the most abundant in active state of the snails. Cellulolytic bacteria were not detected in juveniles of C. aspersum. Escherichia coli, Clostridium perfringens as well as bacteria from the genus Salmonella, Shigella and Pseudomonas were not detected. Bacteria of the genus Aeromonas were found in juveniles of C. aspersum, after that their number decrease and were not found in hibernating snails. On the base of the two applied approaches this study shows that the bacterial flora in the intestinal tract of C. aspersum is affected by the seasonal and environmental variations and undergoes quantitative and qualitative changes during the different states of the life cycle. The snails harbor in their gut intestinal bacteria, which possess biochemical potentiality to degrade the plant components.

The use of organisms in biomonitoring studies allows the determination of the pollution levels, the assessment of the quality of the enviroment and the study of toxic effects of pollutants on the organisms. By studying the responses (biomarkers) of organisms, it is possible to assess the exposure and effects of pollutants. Land gastropods are widely used in relevant studies as they possess several characteristics that make them ideal for use as bioindicators. In the present study we sought to evaluate several biomarkers in the laboratory using snails of the species Cornu aspersum after the exposure to heavy metals (Cd, Hg) and a mixture of polycyclic aromatic hydrocarbons (PAHs) (anthracene, phenanthrene and naphthalene). The biomarkers studied were the following: lysosomic membrane stability using the neutral red retention assay (NRR), the production of reactive oxygen species (ROS) using the compound DCFH-DA and flow cytometry, lipid peroxidation using the TBARs assay that measures the concentration of malondialdehyde (MDA), protein carbonylation (–CO) using ELISA, and single strand breaks of DNA using the comet assay. Our results show significant differences in the responses between the control group and the groups that were exposed to pollutans, enhancing the role of Cornu aspersum as a promising bioindicator organism in terrestrial pollution studies with the use of the biomarkers applied. [ABSTRACT FROM AUTHOR]

The uptake of Cd and some biomarkers of exposure and effects have been investigated in specimens of land snail Cornu aspersum exposed to vaporized CdCl 2 (10 mg/L) for 7 days. The Cd levels quantified in snail's whole bodies confirmed Cd bioavailability trough vaporization and an higher accumulation in the midgut gland compared to the foot. Biological responses investigated showed a reduction of destabilization time of lysosomal membranes (NRRT) in hemocytes and an induction of catalase activities (CAT) in midgut gland. A further evidence of CdCl 2 vaporized exposure was given by an increase in MT protein content as well as induction of Cd-MT gene expression, highlighting the central role of the midgut gland in Cd detoxification. These biomarkers can thus be considered as sensitive tools for the assessment of Cd contamination in the air using land snails as bioindicators. No changes in of GST activity and MDA were observed. From the overall results, the land snail, C. aspersum , could be used as good bioindicator of air quality for pollution monitoring purposes having shown clear signs of exposure and effects due Cd exposure by air. [ABSTRACT FROM AUTHOR]

Intraspecific variation in sexual traits may arise from a variety of processes such as genetic drift, sexual selection, or spatial heterogeneity of environmental conditions. Recent empirical studies suggest that sexual selection may vary with environmental conditions accelerating differentiation of sexual traits among populations. Land snails are simultaneously hermaphroditic animals characterized by low mobility and limited dispersal, so that life cycle characteristics of their populations are strongly influenced by local environmental conditions. In this study, we report results on intraspecific variation in sexual selection intensity as well as in behavioral and anatomical reproductive traits in the land snail Cornu aspersum. We performed a common garden experiment of adult snails originating from four populations from either of two regions in Greece differing in habitat temperature and predictability of rainfall during their reproductive season. Our results indicate substantial intraspecific variation in the opportunity for sexual selection, which was associated with differences in both behavioral and anatomical reproductive characters. Snails from populations that experienced unpredictable habitat conditions expanded their reproductive activity period, exhibited higher mating frequency, and showed longer copulation duration, relative to snails living in more predictable habitats. Additionally, snails originating from populations with unpredictable habitat conditions showed a distinct reproductive morphology with a shorter bursa tract length, which we interpret as indicative of an enhanced ability to hydrolyze the received spermatophores. We conclude that local environmental conditions experienced by the different populations could have triggered differences in the opportunity for sexual selection, which may ultimately lead to allopatric speciation through sexual selection. Significance statement: Environment-dependent sexual selection is considered to promote allopatric speciation of distant populations. However, empirical studies testing for geographic differences in the strength of sexual selection and associated reproductive characters are scarce. In C. aspersum, variation in both behavioral and anatomical reproductive traits among populations is well-documented, but the extent to which this is driven by diverse pressures of sexual selection under heterogeneous environmental conditions among populations remains unexplored. We demonstrate that snails from two geographically distant regions of Greece, with contrasting natural habitats, differ mainly in their behavioral traits and in several morphological traits, which are associated with differences in the opportunity for pre- and post-copulatory sexual selection. [ABSTRACT FROM AUTHOR]